METREL MI 3125 Eurotes Combo Insulation Tester Instruction Manual

UP/DOWN TAB TEST MEM

Selects sub-function in selected measurement function. Selects the test parameter to be set or modified. Runs selected test / measurement function. Stores measured results / recalls stored results (model MI 3125 BT).

Keys in test parameter field:

UP/DOWN TAB FUNCTION SELECTOR
MEM

Changes the selected parameter. Selects the next measuring parameter. Toggles between the main functions. Stores measured results / recalls stored results (model MI 3125 BT).

General rule regarding enabling parameters for evaluation of measurement / test result:

OFF Parameter ON

No limit values, indication: _.
Value(s) ­ results will be marked as PASS or FAIL in accordance with selected limit.

See Chapter 5 for more information about the operation of the instrument test functions.

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Instrument operation

4.2 Settings

Different instrument options can be set in the SETTINGS menu.
All models: Selection of language, Setting the instrument to initial values, Selection of reference standard for RCD test, Entering Isc factor, Commander support.

Model MI 3125 BT: Recalling and clearing stored results, Setting the date and time

Figure 4.1: Options in Settings menu

Keys:

UP / DOWN

Selects appropriate option.

TEST

Enters selected option.

Function selectors Exits back to main function menu.

4.2.1 Memory (model MI 3125 BT)
In this menu the stored data can be recalled and deleted. See chapter 6 Data handling for more information.

Figure 4.2: Memory options

Keys:

UP / DOWN

Selects option.

TEST

Enters selected option.

Function selectors Exits back to main function menu.

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4.2.2 Language
In this menu the language can be set.

Instrument operation

Figure 4.3: Language selection

Keys:

UP / DOWN

Selects language.

TEST

Confirms selected language and exits to settings menu.

Function selectors Exits back to main function menu.

4.2.3 Date and time (model MI 3125 BT)
In this menu date and time can be set.

Figure 4.4: Setting date and time

Keys:

TAB UP / DOWN TEST Function selectors

Selects the field to be changed. Modifies selected field. Confirms new setup and exits. Exits back to main function menu.

Warning: If the batteries are removed for more than 1 minute the set time and date will be lost.

4.2.4 RCD testing

In this menu the used standard for RCD tests can be set.

Figure 4.5: Selection of RCD test standard
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Instrument operation

Keys:

UP / DOWN

Selects standard.

TEST

Confirms selected standard.

Function selectors Exits back to main function menu.

Maximum RCD disconnection times differ in various standards.

The trip-out times defined in individual standards are listed below.

Trip-out times according to EN 61008 / EN 61009:

½IN*)

IN

2IN

5IN

General RCDs (non-delayed)

t > 300 ms

t < 300 ms

t < 150 ms

t < 40 ms

Selective RCDs (time-delayed)

t > 500 ms

130 ms < t < 500 ms

60 ms < t < 200 ms

50 ms < t < 150 ms

Test according to standard IEC/HD 60364-4-41 has two selectable options: IEC 60364-4-41 TN/IT and IEC 60364-4-41 TT
The options differ to maximum disconnection times as defined in IEC/HD 60364-4-41 Table 41.1.

Trip-out times according to IEC/HD 60364-4-41:

U0***)

½IN*)

IN

TN / IT

120 V t > 800 ms t 800 ms

230 V t > 400 ms t 400 ms

TT

120 V t > 300 ms t 300 ms

230 V t > 200 ms t 200 ms

2IN t < 150 ms

5IN t < 40 ms

Trip-out times according to BS 7671:

½IN*)

IN

2IN

5IN

General RCDs (non-delayed)

t > 1999 ms

t < 300 ms

t < 150 ms

t < 40 ms

Selective RCDs (time-delayed)

t > 1999 ms

130 ms < t < 500 ms

60 ms < t < 200 ms

50 ms < t < 150 ms

Trip-out times according to AS/NZS 3017**):

½IN*)

IN

2IN 5IN

RCD type IN [mA]

t

t

t

t

Note

I

10

40 ms 40 ms 40 ms

II

10 30 > 999 ms 300 ms 150 ms 40 ms

III

30

300 ms 150 ms 40 ms

Maximum break time

IV S

30

999 ms

500 ms 200 ms 150 ms 130 ms 60 ms 50 ms Minimum non-actuating time

) Minimum test period for current of ½IN, RCD shall not trip-out. ) Test current and measurement accuracy correspond to AS/NZS 3017 requirements. ) U0 is nominal ULPE voltage.

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Instrument operation

Maximum test times related to selected test current for general (non-delayed) RCD

Standard

½IN

IN

2IN

5IN

EN 61008 / EN 61009

300 ms

300 ms

150 ms 40 ms

IEC 60364-4-41

1000 ms

1000 ms

150 ms 40 ms

BS 7671

2000 ms

300 ms

150 ms 40 ms

AS/NZS 3017 (I, II, III)

1000 ms

1000 ms

150 ms 40 ms

Maximum test times related to selected test current for selective (time- delayed) RCD

Standard

½IN

IN

2IN

5IN

EN 61008 / EN 61009

500 ms

500 ms

200 ms 150 ms

IEC 60364-4-41

1000 ms

1000 ms

200 ms 150 ms

BS 7671

2000 ms

500 ms

200 ms 150 ms

AS/NZS 3017 (IV)

1000 ms

1000 ms

200 ms 150 ms

4.2.5 Isc factor

In this menu the Isc factor for calculation of short circuit current in Z-LINE and Z-LOOP measurements can be set.

Keys:
UP / DOWN TEST Function selectors

Figure 4.6: Selection of Isc factor
Sets Isc value. Confirms Isc value. Exits back to main function menu.

Short circuit current Isc in the supply system is important for selection or verification of protective circuit breakers (fuses, over-current breaking devices, RCDs). The default value of Isc factor (ksc) is 1.00. The value should be set according to local regulative.
Range for adjustment of the Isc factor is 0.20 3.00.

4.2.6 Commander support
The support for commanders can be set in this menu.

Figure 4.7: Selection of commander support 26

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Instrument operation

Keys:
UP / DOWN TEST Function selectors

Selects commander model. Disables commander support. Confirms selected option. Exits back to main function menu.

Commander models A1314, A1401: new commanders (more information can be found in Appendix E)

Note:
Commander disabled is intended to disable the commander’s remote keys. In the case of high EM interfering noise the operation of the commander’s key can be irregular.

4.2.7 Initial settings

In this menu the instrument settings and measurement parameters and limits can be set to initial (factory) values. Internal Bluetooth module is initialized. (MI 3125 BT only)

Figure 4.8: Initial settings dialogue

Keys: TEST
Function selectors

Restores default settings (YES must be selected with / keys).
Exits back to main function menu without changes.

Warnings:
Customized settings will be lost when this option is used! If the batteries are removed for more than 1 minute the custom made settings will
be lost.

The default setup is listed below:

Instrument setting Contrast Isc factor RCD standards Language Commander Internal bluetooth

Default value As defined and stored by adjustment procedure 1.00 EN 61008 / EN 61009 English A1314, A1401 Initialization of internal Bluetooth module. (MI 3125 BT only)

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Instrument operation

Function Sub-function
EARTH RE R ISO
Low Ohm Resistance R LOW CONTINUITY
Z – LINE VOLTAGE DROP
Z – LOOP Zs rcd
RCD

Parameters / limit value
No limit No limit Utest = 500 V

No limit

No limit

Fuse type: none selected

U: 4.0 %

ZREF: 0.00 Fuse type: none selected

Test current: standard

Fuse type: none selected

RCD t

Nominal differential current: IN=30 mA

RCD type: AC non-delayed

Test current starting polarity:

(0)

Limit contact voltage: 50 V

Current multiplier: 1

Note: Initial settings (reset of the instrument) can be recalled also if the TAB key is pressed while the instrument is switched on.

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Measurements

5 Measurements

5.1 Voltage, frequency and phase sequence

Voltage and frequency measurement is always active in the terminal voltage monitor. In the special VOLTAGE TRMS menu the measured voltage, frequency and information about detected three-phase connection can be stored. Phase sequence measurement conforms to the EN 61557-7 standard.

See chapter 4.1 Function selection for instructions on key functionality.

Test parameters for voltage measurement There are no parameters to set. Connections for voltage measurement

Figure 5.1: Voltage in single phase system

Figure 5.2: Connection of 3-wire test lead and optional adapter in three-phase system

Figure 5.3: Connection of plug commander and 3-wire test lead in single-phase system 29

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Measurements

Voltage measurement procedure

• model MI 3125 BT Select the VOLTAGE TRMS function using the function selector switch. Connect test cable to the instrument. Connect test leads to the item to be tested (see figures 5.2 and 5.3). Store voltage measurement result by pressing the MEM key (optional)*.

Measurement runs immediately after selection of VOLTAGE TRMS function.

Figure 5.4: Examples of voltage measurement in three-phase system
Displayed results for single phase system: Uln………..Voltage between phase and neutral conductors, Ulpe………Voltage between phase and protective conductors, Unpe……..Voltage between neutral and protective conductors, f …………… frequency.
Displayed results for three-phase system: U12……….Voltage between phases L1 and L2, U13……….Voltage between phases L1 and L3, U23……….Voltage between phases L2 and L3, 1.2.3 …….. Correct connection ­ CW rotation sequence, 3.2.1 …….. Invalid connection ­ CCW rotation sequence, f …………… frequency.

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Measurements

5.2 Insulation resistance

The Insulation resistance measurement is performed in order to ensure safety against electric shock through insulation. It is covered by the EN 61557-2 standard. Typical applications are:
Insulation resistance between conductors of installation, Insulation resistance of non-conductive rooms (walls and floors), Insulation resistance of ground cables, Resistance of semi-conductive (antistatic) floors.

See chapter 4.1 Function selection for instructions on key functionality.

Figure 5.5: Insulation resistance

Test parameters for insulation resistance measurement

Uiso Limit

Test voltage [50 V, 100 V, 250 V, 500 V, 1000 V] Minimum insulation resistance [OFF, 0.01 M ÷ 200 M]

Test circuits for insulation resistance

Figure 5.6: Connections for insulation measurement

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Measurements

Insulation resistance measuring procedure

• model MI 3125 BT Select the INS function using the function selector switch. Set the required test voltage. Enable and set limit value (optional). Disconnect tested installation from mains supply (and discharge insulation as required). Connect test cable to the instrument and to the item to be tested (see figure 5.6). Press the TEST key to perform the measurement (double click for continuous measurement and later press to stop the measurement). After the measurement is finished wait until tested item is fully discharged. Store the result by pressing the MEM key (optional)*.

Figure 5.7: Example of insulation resistance measurement result
Displayed results: R…………………….Insulation resistance Um………………….Test voltage ­ actual value.

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Measurements

5.3 Resistance of earth connection and equipotential bonding

The resistance measurement is performed in order to ensure that the protective measures against electric shock through earth connections and bondings are effective. Two sub-functions are available:
R LOW – Earth bond resistance measurement according to EN 61557-4 (200 mA),
CONTINUITY – Continuous resistance measurement performed with 7 mA.

See chapter 4.1 Function selection for instructions on key functionality.

Test parameters for resistance measurement

Figure 5.8: 200 mA RLOW

TEST Limit

Resistance measurement sub-function [R LOW, CONTINUITY] Maximum resistance [OFF, 0.1 ÷ 20.0 ]

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Measurements

5.3.1 R LOW, 200 mA resistance measurement
The resistance measurement is performed with automatic polarity reversal of the test voltage.
Test circuit for R LOW measurement

Figure 5.9: Connection of 3-wire test lead plus optional extension lead
Resistance to earth connection and equipotential bonding measurement procedure

• model MI 3125 BT
  Select continuity function using the function selector switch. Set sub- function to R LOW. Enable and set limit (optional). Connect test cable to the instrument. Compensate the test leads resistance (if necessary, see section 5.3.3). Disconnect from mains supply and discharge installation to be tested. Connect the test leads to the appropriate PE wiring (see figure 5.9). Press the TEST key to perform the measurement. After the measurement is finished store the result by pressing the MEM button
  (optional)*.
  Figure 5.10: Example of RLOW result
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Measurements

Displayed result: R…………….R LOW resistance. R+…………..Result at positive polarity R-……………Result at negative test polarity
5.3.2 Continuous resistance measurement with low current

In general, this function serves as standard -meter with a low testing current. The measurement is performed continuously without polarity reversal. The function can also be applied for testing continuity of inductive components.

Test circuit for continuous resistance measurement

Figure 5.11: 3-wire test lead application Continuous resistance measurement procedure model MI 3125 BT
Select continuity function using the function selector switch. Set sub- function CONTINUITY. Enable and set the limit (optional). Enable sound (optional). Connect test cable to the instrument. Compensate test leads resistance (if necessary, see section 5.3.3). Disconnect from mains supply and discharge the object to be tested. Connect test leads to the tested object (see figure 5.11). Press the TEST key to begin performing a continuous measurement. Press the TEST key to stop measurement. After the measurement is finished, store the result (optional).
Figure 5.12: Example of continuous resistance measurement
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Measurements

Displayed result: R…………Resistance
Notes: Continuous buzzer sound indicates that measured resistance PASS the limit.
There is no sound if the limit is disabled (—).

5.3.3 Compensation of test leads resistance

This chapter describes how to compensate the test leads resistance in both continuity functions, R LOW and CONTINUITY. Compensation is required to eliminate the influence of test leads resistance and the internal resistances of the instrument on the measured resistance. The lead compensation is therefore a very important feature to obtain correct result.

R LOW and CONTINUITY has common compensation. compensation was carried out successfully.

symbol is displayed if the

Circuits for compensating the resistance of test leads

Figure 5.13: Shorted test leads
Compensation of test leads resistance procedure
Select R LOW or CONTINUITY function. Connect test cable to the instrument and short the test leads together (see figure
5.13). Press TEST to perform resistance measurement. Press the CAL key to compensate leads resistance.

Figure 5.14: Results with old calibration values

Figure 5.15: Results with new calibration values

Note: The highest value for lead compensation is 5 . If the resistance is higher the compensation value is set back to default value.
is displayed if no calibration value is stored.

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Measurements

5.4 Testing RCDs

Various test and measurements are required for verification of RCD(s) in RCD protected installations. Measurements are based on the EN 61557-6 standard. The following measurements and tests (sub-functions) can be performed:
Contact voltage, Trip-out time, Trip-out current, RCD autotest.

See chapter 4.1 Function selection for instructions on key functionality.

Figure 5.16: RCD test

Test parameters for RCD test and measurement

TEST RCD sub-function test [RCDt, RCD I, AUTO, Uc].

IN

Rated RCD residual current sensitivity IN, IN(DC), [6 mA, 30/6 mA, 10 mA,

30 mA, 100 mA, 300 mA, 500 mA, 1000 mA].

type RCD type [AC, A, F, B, B+, EV*], starting polarity [ , , , , , *],

selective S or general non-delayed characteristic

MUL Multiplication factor for test current [½, 1, 2, 5 IN]. Ulim Conventional touch voltage limit [25 V, 50 V].

• Model MI 3125 BT

** EV RCD

Notes: Ulim can be selected in the Uc sub-function only. Selective (time delayed) RCDs have delayed response characteristics. As the contact voltage pre-test or other RCD tests influence the time delayed RCD it takes a certain period to recover into normal state. Therefore a time delay of 30 s is inserted before performing trip-out test by default. The a.c. part of EV RCDs is tested according to EN 61008 / EN 61009 as general (non-delayed) RCDs. The d.c. part of EV RCDs is tested with a DC test current. The Pass limit is
between 0.5 and 1.0 IN(DC).

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Measurements

Figure 5.17: Connecting the plug commander and the 3-wire test lead
5.4.1 Contact voltage (RCD Uc)
A current flowing into the PE terminal causes a voltage drop on earth resistance, i.e. voltage difference between PE equipotential bonding circuit and earth. This voltage difference is called contact voltage and is present on all accessible conductive parts connected to the PE. It shall always be lower than the conventional safety limit voltage. The contact voltage is measured with a test current lower than ½ IN to avoid trip-out of the RCD and then normalized to the rated IN. Contact voltage measurement procedure model MI 3125 BT
Select the RCD function using the function selector switch. Set sub-function Uc. Set test parameters (if necessary). Connect test cable to the instrument. Connect test leads to the item to be tested (see figure 5.17). Press the TEST key to perform the measurement. Store the result by pressing the MEM key (optional).
The contact voltage result relates to the rated nominal residual current of the RCD and is multiplied by an appropriate factor (depending on RCD type and type of test current). The 1.05 factor is applied to avoid negative tolerance of result. See table 5.1 for detailed contact voltage calculation factors.
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Measurements

RCD type
AC AC A, F A, F A, F A, F EV (a.c. part) B, B+ B, B+

Contact voltage Uc proportional to

Rated IN

1.05IN

any

S

21.05IN

1.41.05IN S 21.41.05IN

30 mA

All models

21.05IN

< 30 mA

S

221.05IN

1.05IN

21.05IN

any Model MI 3125 BT

S

221.05IN

Table 5.1: Relationship between Uc and IN

Loop resistance is indicative and calculated from Uc result (without additional

proportional

factors)

according

to: RL

UC IN

.

Figure 5.18: Example of contact voltage measurement results
Displayed results: Uc……..Contact voltage. Rl………Fault loop resistance.
5.4.2 Trip-out time (RCDt)
Trip-out time measurement verifies the sensitivity of the RCD at different residual currents.
Trip-out time measurement procedure model MI 3125 BT
Select the RCD function using the function selector switch. Set sub-function RCDt. Set test parameters (if necessary). Connect test cable to the instrument. Connect test leads to the item to be tested (see figure 5.17). Press the TEST key to perform the measurement. Store the result by pressing the MEM key (optional).
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Measurements

Figure 5.19: Example of trip-out time measurement results

Displayed results: t ………..Trip-out time, Uc……..Contact voltage for rated IN.
5.4.3 Trip-out current (RCD I)

A continuously rising residual current is intended for testing the threshold sensitivity for RCD trip-out. The instrument increases the test current in small steps through appropriate range as follows:

RCD type

Slope range Start value End value

Waveform

Note

AC

0.2IN

1.1IN

Sine

A, F (IN 30 mA) A, F (IN = 10 mA)

0.2IN 0.2IN

1.5IN 2.2IN

Pulsed

All models

EV (a.c. part)

0.2IN

1.1IN

Sine

B, B+ EV (d.c. part)

0.2IN

2.2IN

DC

0.2IN(DC) 1.0IN(DC)

Model MI 3125 BT

Maximum test current is I (trip-out current) or end value in case the RCD didn’t trip-out.

Trip-out current measurement procedure

• model MI 3125 BT Select the RCD function using the function selector switch. Set sub-function RCD I. Set test parameters (if necessary). Connect test cable to the instrument. Connect test leads to the item to be tested (see figure 5.17). Press the TEST key to perform the measurement. Store the result by pressing the MEM key (optional)*.

Trip-out

After the RCD is turned on again

Figure 5.20: Trip-out current measurement result example

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Measurements

Displayed results: I ………..Trip-out current, Uci Contact voltage at trip-out current I or end value in case the RCD didn’t
trip, t ………..Trip-out time.

5.4.4 RCD Autotest

RCD autotest function is intended to perform a complete RCD test (trip-out time at different residual currents, trip-out current and contact voltage) in one set of automatic tests, guided by the instrument.

Additional key: HELP / DISPLAY

Toggles between top and bottom part of results field.

RCD autotest procedure

• model MI 3125 BT RCD Autotest steps Select the RCD function using the function selector
  switch. Set sub-function AUTO. Set test parameters (if necessary). Connect test cable to the instrument. Connect test leads to the item to be tested (see figure
  5.17). Press the TEST key to perform the test.
  Test with IN, 0 (step 1). Re-activate RCD.
  Test with IN, 180 (step 2). Re-activate RCD.
  Test with 5IN, 0 (step 3). Re-activate RCD.
  Test with 5IN, 180 (step 4). Re-activate RCD.
  Test with ½IN, 0 (step 5). Test with ½IN, 180 (step 6). Trip-out current test, 0 (step 7). Re-activate RCD.
  Trip-out current test, 180 (step 8). Re-activate RCD. Test with IN(DC), +DC (step 9). 1) Re-activate RCD. Test with IN(DC), -DC (step 10). 1) Re-activate RCD. Store the result by pressing the MEM key (optional)*.

1. Steps 9 and 10 are performed for EV RCD only.

Notes
Start of test RCD should trip-out RCD should trip-out RCD should trip-out RCD should trip-out RCD should not trip-out RCD should not trip-out RCD should trip-out RCD should trip-out RCD should trip-out RCD should trip-out End of test

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Step 1 Step 3 Step 5 Step 7

Measurements Step 2 Step 4 Step 6 Step 8

Step 9

Step 10

Figure 5.21: Individual steps in RCD autotest

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Measurements

Top

Bottom

Figure 5.22: Two parts of result field in RCD autotest

Displayed results: x1 ……..Step 1 trip-out time ( , IN, 0º), x1 ……..Step 2 trip-out time ( , IN, 180º), x5 ……..Step 3 trip-out time ( , 5IN, 0º), x5 ……..Step 4 trip-out time ( , 5IN, 180º), x½ …….Step 5 trip-out time ( , ½IN, 0º), x½ …….Step 6 trip-out time ( , ½IN, 180º), I ………Step 7 trip-out current (0º), I ………Step 8 trip-out current (180º), tdc …….Step 9 trip-out time (+ DC), tdc …….Step 10 trip-out time (- DC), Uc……..Contact voltage for rated IN.
Notes: The autotest sequence is immediately stopped if any incorrect condition is detected, e.g. excessive Uc or trip-out time out of bounds. Auto test is finished without x5 tests in case of testing the RCD types A, F with rated residual currents of In = 300 mA, 500 mA, and 1000 mA. In this case auto test result passes if all other results pass, and indications for x5 are omitted. Tests for sensitivity (I, steps 7 and 8) are omitted for selective type RCD. Trip out time measurement for B and B+ type RCDs in AUTO function is made with sine-wave test current, while trip-out current measurement is made with DC test current (MI 3125 BT only). AC part for EV type RCDs in AUTO function is tested with sine-wave test current using trip-out time measurement and trip- out current measurement, while trip-out time measurement for DC part is made with DC test current (MI 3125 BT only).

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Measurements

5.5 Fault loop impedance and prospective fault current

Fault loop is a loop comprised by mains source, line wiring and PE return path to the mains source. The instrument measures the impedance of the loop and calculates the short circuit current. The measurement is covered by requirements of the EN 61557-3 standard.

See chapter 4.1 Function selection for instructions on key functionality.

Figure 5.23: Fault loop impedance

Test parameters for fault loop impedance measurement

Test

Selection of fault loop impedance sub-function [Zloop, Zs rcd]

I test*

Selection of test current [Std, Low]

Fuse type

Selection of fuse type [—, NV, gG, B, C, K, D]

Fuse I

Rated current of selected fuse

Fuse T

Maximum breaking time of selected fuse

Lim

Minimum short circuit current for selected fuse.

*Applicable only in Zs rcd (some models)

See Appendix A for reference fuse data.

Circuits for measurement of fault loop impedance

Figure 5.24: Connection of plug commander and 3-wire test lead 44

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Measurements

Fault loop impedance measurement procedure

• model MI 3125 BT Select the Zloop or Zs rcd sub-function using the function selector switch and / keys Select test parameters (optional). Connect test cable to the Eurotest Combo. Connect test leads to the item to be tested (see figure 5.24 and 5.17). Press the TEST key to perform the measurement. Store the result by pressing the MEM key (optional)*.

Figure 5.25: Examples of loop impedance measurement result

Displayed results: Z ………….. Fault loop impedance, ISC…………Prospective fault current, Lim ………. Low limit prospective fault loop current value or high limit fault loop
impedance value for the UK version.

Prospective fault current ISC is calculated from measured impedance as follows:

ISC

Un

kSC Z

where:

Un …….. Nominal UL-PE voltage (see table below),

ksc ……. Correction factor for Isc (see chapter 4.2.5).

Un Input voltage range (L-PE) 110 V (93 V UL-PE 134 V) 230 V (185 V UL-PE 266 V)

Notes: High fluctuations of mains voltage can influence the measurement results (the noise sign is displayed in the message field). In this case it is recommended to repeat few measurements to check if the readings are stable. This measurement will trip-out the RCD in RCD-protected electrical installation if test Zloop is selected. Select Zs rcd to prevent trip-out of RCD in RCD protected installation.

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Measurements

5.6 Line impedance and prospective short-circuit current / Voltage drop

Line impedance is measured in loop comprising of mains voltage source and line wiring. Line impedance is covered by the requirements of the EN 61557-3 standard. The Voltage drop sub-function is intended to check that a voltage in the installation stays above acceptable levels if the highest current is flowing in the circuit. The highest current is defined as the nominal current of the circuit’s fuse. The limit values are described in the standard IEC 60364-5-52.
Sub-functions:
Z LINE- Line impedance measurement according to EN 61557-3, U ­ Voltage drop measurement.

See chapter 4.1 Function selection for instructions on key functionality.

Figure 5.26: Line impedance

Figure 5.27: Voltage drop

Test parameters for line impedance measurement

Test

Selection of line impedance [Zline] or voltage drop [U] sub-function

FUSE type Selection of fuse type [—, NV, gG, B, C, K, D]

FUSE I

Rated current of selected fuse

FUSE T

Maximum breaking time of selected fuse

Lim

Minimum short circuit current for selected fuse.

See Appendix A for reference fuse data.

Additional test parameters for voltage drop measurement

UMAX

Maximum voltage drop [3.0 % ÷ 9.0 %].

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Measurements

Figure 5.28: Phase-neutral or phase-phase line impedance measurement ­ connection of plug commander and 3-wire test lead
Line impedance measurement procedure

• model MI 3125 BT Select the Z-LINE sub-function. Select test parameters (optional). Connect test cable to the instrument. Connect test leads to the item to be tested (see figure 5.28). Press the TEST key to perform the measurement. Store the result by pressing the MEM key (optional)*.

Line to neutral

Line to line

Figure 5.29: Examples of line impedance measurement result

Displayed results: Z ………….. Line impedance, ISC…………Prospective short-circuit current, Lim ………. Low limit prospective short-circuit current value.

Prospective short circuit current is calculated as follows:

ISC

Un kSC Z

where:

Un …….. Nominal L-N or L1-L2 voltage (see table below),

ksc ……. Correction factor for Isc (see chapter 4.2.5).

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Note:

Un Input voltage range (L-N or L1-L2)

110 V

(93 V UL-N 134 V)

230 V

(185 V UL-N 266 V)

400 V

(321 V UL-L 485 V)

High fluctuations of mains voltage can influence the measurement results (the noise sign is displayed in the message field). In this case it is recommended to repeat few measurements to check if the readings are stable.

5.6.1 Voltage drop
The voltage drop is calculated based on the difference of line impedance at connection points (sockets) and the line impedance at the reference point (usually the impedance at the switchboard).
Circuits for measurement for voltage drop

Figure 5.30: Phase-neutral or phase-phase voltage drop measurement ­ connection of plug commander and 3-wire test lead
Voltage drop measurement procedure
Step 1: Measuring the impedance Zref at origin Select the U sub-function using the function selector switch and / keys. Select test parameters (optional). Connect test cable to the instrument. Connect the test leads to the origin of electrical installation (see figure 5.30). Press the CAL key to perform the measurement.
Step 2: Measuring the voltage drop Select the U sub-function using the function selector switch and / keys. Select test parameters (Fuse type must be selected). Connect test cable or plug commander to the instrument. Connect the test leads to the tested points (see figure 5.30). Press the TEST key to perform the measurement. Store the result by pressing the MEM key (optional)*.

• model MI 3125 BT
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Measurements

Step 1 – Zref

Step 2 – Voltage drop

Figure 5.31: Examples of voltage drop measurement result

Displayed results: U ……….. Voltage drop, ISC…………Prospective short-circuit current, Z ………….. Line impedance at measured point, Zref……….Reference impedance

Voltage drop is calculated as follows:

U % (Z Z REF ) I N 100
UN
where:
U…….. calculated voltage drop Z………impedance at test point ZREF……impedance at reference point IN………rated current of selected fuse UN…….nominal voltage (see table below)

Note:

Un Input voltage range (L-N or L1-L2)

110 V

(93 V UL-N 134 V)

230 V

(185 V UL-N 266 V)

400 V

(321 V UL-L 485 V)

If the reference impedance is not set the value of ZREF is considered as 0.00 . The ZREF is cleared (set to 0.00 ) if pressing CAL key while instrument is not
connected to a voltage source. ISC is calculated as described in chapter 5.6.1 Line impedance and prospective
short circuit current. If the measured voltage is outside the ranges described in the table above the
U result will not be calculated. High fluctuations of mains voltage can influence the measurement results (the
noise sign is displayed in the message field). In this case it is recommended
to repeat few measurements to check if the readings are stable.

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Measurements

5.7 Earth resistance

Earth resistance is one of the most important parameters for protection against electric shock. Main earthing arrangements, lightning systems, local earthings, etc can be verified with the earthing resistance test. The measurement conforms to the EN 615575 standard.

See chapter 4.1 Function selection for instructions on key functionality.

Test parameters for earth resistance measurement

Limit

Maximum resistance OFF, 1 ÷ 5 k

Figure 5.32: Earth resistance

Connections for earth resistance measurement

Figure 5.33: Resistance to earth, measurement of main installation earthing

Figure 5.34: Resistance to earth, measurement of a lightning protection system 50

MI 3125 / BT EurotestCOMBO

Measurements

Earth resistance measurements, common measurement procedure

• model MI 3125 BT
  Select EARTH function using the function selector switch. Enable and set limit value (optional). Connect test leads to the instrument Connect the item to be tested (see Figure 5.33 and Figure 5.34). Press the TEST key to perform the measurement. Store the result by pressing the MEM key (optional)*.

Figure 5.35: Example of earth resistance measurement result
Displayed results for earth resistance measurement: R………….. Earth resistance, Rp………… Resistance of S (potential) probe, Rc…………Resistance of H (current) probe.
Notes: High resistance of S and H probes could influence the measurement results. In this case, “Rp” and “Rc” warnings are displayed. There is no pass / fail indication in this case. High noise currents and voltages in earth could influence the measurement results. The tester displays the “noise” warning in this case. Probes must be placed at sufficient distance from the measured object.
5.8 PE test terminal
It can happen that a dangerous voltage is applied to the PE wire or other accessible metal parts. This is a very dangerous situation since the PE wire and MPEs are considered to be earthed. An often reason for this fault is incorrect wiring (see examples below). When touching the TEST key in all functions that require mains supply the user automatically performs this test.

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Measurements

Figure 5.36: Reversed L and PE conductors (application of plug commander)

Figure 5.37: Reversed L and PE conductors (application of 3-wire test lead)
Reversed phase and protection conductors! The most dangerous situation!
PE terminal test procedure Connect test cable to the instrument. Connect test leads to the item to be tested (see Figure 5.36 and Figure 5.37). Touch PE test probe (the TEST key) for at least one second. If PE terminal is connected to phase voltage the warning message is displayed, instrument buzzer is activated, and further measurements are disabled in ZLOOP and RCD functions.
Warning: If dangerous voltage is detected on the tested PE terminal, immediately stop all measurements, find and remove the fault!
Notes: In the SETTINGS and VOLTAGE TRMS menus the PE terminal is not tested. PE test terminal does not operate in case the operator’s body is completely insulated from floor or walls!
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Data handling

6 Data handling (model MI 3125 BT)

6.1 Memory organization

Measurement results together with all relevant parameters can be stored in the
instrument’s memory. After the measurement is completed, results can be stored to the flash memory of the instrument, together with the sub-results and function parameters.

6.2 Data structure
The instrument’s memory place is divided into two 4 level data structures. The number of measurements that can be stored into one location is not limited.
The data structure field describes the location of the measurement (which object, block, fuse, connection or which EVSE, sublevel) and where can be accessed. In the measurement field there is information about type and number of measurements that belong to the selected structure element (object, block, fuse, connection, EVSE, level). The main advantages of this system are:
Test results can be organized and grouped in a structured manner that reflects the structure of typical electrical installations and EVSEs.
Customized names of data structure elements can be uploaded from EurolinkPRO PCSW.
Simple browsing through structure and results. Test reports can be created with no or little modifications after downloading
results to a PC.

Figure 6.1: Object and EVSE data structure fields Note:
The descriptions in this Instruction manual mainly refer to an Object data structure. Operation is the same if working with an EVSE data structure.
Data structure field 53

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Data handling

Measurement field

Memory operation menu
Data structure field
1st level: OBJECT: Default location name (object and its successive number). 004: No. of selected element. 2nd level: BLOCK: Default location name (block and its successive number). 001: No. of selected element. 3rd level: FUSE: Default location name (fuse and its successive number). 002: No. of selected element. 4th level: CONNECTION: Default location name (connection and its successive number). 003: No. of selected element. No. of measurements in selected location [No. of measurements in selected location and its sublocations].
Type of stored measurement in the selected location. No. of selected test result / No. of all stored test results in selected location.

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Data handling

6.3 Storing test results

After the completion of a test the results and parameters are ready for storing ( icon is displayed in the information field). By pressing the MEM key, the user can store the results.

Figure 6.2: Save test menu

Memory available for storing results.

Keys in save test menu – data structure field:

TAB UP / DOWN MEM Function selector / TEST

Selects the location element (Object / Block / Fuse / Connection). Selects number of selected location element (1 to 199). Saves test results to the selected location and returns to the measuring menu. Exits back to main function menu.

Notes: The instrument offers to store the result to the last selected location by default. If the measurement is to be stored to the same location as the previous one just press the MEM key twice

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Data handling

6.4 Recalling test results

Press the MEM key in a main function menu when there is no result available for storing or select MEMORY in the SETTINGS menu.

Figure 6.3: Recall menu – installation structure field selected

Figure 6.4: Recall menu – measurements field selected

Keys in recall memory menu (installation structure field selected):

TAB

Selects the location element (Object / Block / Fuse / Connection).

UP / DOWN

Selects number of selected location element (1 to 199).

Function TEST

selector

/

Exits back to main function menu.

MEM

Enters measurements field.

Keys in recall memory menu (measurements field):

UP / DOWN

Selects the stored measurement.

TAB

Returns to installation structure field.

Function TEST

selector

/

Exits back to main function menu.

MEM

View selected measurement results.

Figure 6.5: Example of recalled measurement result

Keys in recall memory menu (measurement results are displayed)

UP / DOWN MEM Function selector / TEST

Displays measurement results stored in selected location. Returns to measurements field.
Exits back to main function menu.

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Data handling

6.5 Clearing stored data

6.5.1 Clearing complete memory content
Select CLEAR ALL MEMORY in MEMORY menu. A warning will be displayed.

Figure 6.6: Clear all memory

Keys in clear all memory menu

TEST

Confirms clearing of complete memory content.

Function selector Exits back to main function menu without changes.

Figure 6.7: Clearing memory in progress
6.5.2 Clearing measurement(s) in selected location
Select DELETE RESULTS in MEMORY menu.

Figure 6.8: Clear measurements menu (data structure field selected)

Keys in delete results menu (installation structure field selected):

TAB
UP / DOWN Function selector TEST HELP

Selects the location element (Object / Block / Fuse / Connection). Selects number of selected location element (1 to 199). / Exits back to main function menu.
Enters dialog box for deleting all measurements in selected location and its sub-locations.

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Data handling

Keys in dialog for confirmation to clear results in selected location:

HELP TAB / MEM Function selector TEST

Deletes all results in selected location. Exits back to delete results menu without changes. / Exits back to main function menu without changes.

6.5.3 Clearing individual measurements
Select DELETE RESULTS in MEMORY menu.

Figure 6.9: Menu for clearing individual measurement (installation structure field selected)

Keys in delete results menu (installation structure field selected):

TAB
UP / DOWN Function selector TEST MEM

Selects the location element (Object / Block / Fuse / Connection). Selects number of selected location element (1 to 199). / Exits back to main function menu.
Enters measurements field for deleting individual measurements.

Keys in delete results menu (measurements field selected):

UP / DOWN

Selects measurement.

HELP

Opens dialog box for confirmation to clear

measurement.

TAB

Returns to installation structure field.

Function TEST

selector

/

Exits back to main function menu without changes.

selected

Keys in dialog for confirmation to clear selected result(s):

HELP MEM / TAB Function selector TEST

Deletes selected measurement result. Exits back to measurements field without changes. / Exits back to main function menu without changes.

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Data handling

Figure 6.10: Dialog for confirmation

Figure 6.11: Display after measurement was cleared

6.5.4 Renaming installation structure elements (upload from PC)

Default installation structure elements are “Object”, “Block”, “Fuse” and “Connection”. In the PCSW package Eurolink-PRO default names can be changed with customized names that corresponds the installation under test. Refer to PCSW Eurolink-PRO HELP for information how to upload customized installation names to the instrument.

Figure 6.12: Example of menu with customized installation structure names
6.5.5 Renaming installation structure elements with serial barcode reader or RFID reader
Default installation structure elements are “Object”, “Block”, “Fuse” and “Connection”. When the instrument is in the Save results menu location ID can be scanned from a barcode label with the barcode reader or can be read from a RFID tag with the RFID reader.

Figure 6.13: Connection of the barcode reader and RFID reader 59

MI 3125 / BT EurotestCOMBO

Data handling

How to change the name of memory location
Connect the barcode reader or RFID reader to the instrument. In Save menu select memory location to be renamed. A new location name (scanned from a barcode label or a RFID tag) will be
accepted by the instrument. A successful receive of the barcode or RFID tag is confirmed by two short confirmation beeps.

Note: Use only barcode readers and RFID readers delivered by Metrel or authorized distributor.

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Data handling

6.6 Communication (model MI 3125 BT)

Stored results can be transferred to a PC. A special communication program on the PC automatically identifies the instrument and enables data transfer between the instrument and the PC. There are three communication interfaces available: USB, RS 232 and Bluetooth.

6.6.1 USB and RS232 communication

The instrument automatically selects the communication mode according to detected interface. USB interface has priority.

Figure 6.14: Interface connection for data transfer over PC COM port
How to establish an USB or RS232 link:
RS-232 communication: connect a PC COM port to the instrument PS/2 connector using the PS/2 – RS232 serial communication cable;
USB communication: connect a PC USB port to the instrument USB connector using the USB interface cable.
Switch on the PC and the instrument. Run the EurolinkPRO program. The PC and the instrument will automatically recognize each other. The instrument is prepared to communicate with the PC.
The program EurolinkPRO is a PC software running on Windows XP, Windows Vista, Windows 7, and Windows 8. Read the file README_EuroLink.txt on CD for instructions about installing and running the program.
Note: USB drivers should be installed on PC before using the USB interface. Refer to USB installation instructions available on installation CD.

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Data handling

6.6.2 Bluetooth communication

The internal Bluetooth module enables easy communication via Bluetooth with PC and Android devices.
How to configure a Bluetooth link between instrument and PC

Switch On the instrument. On PC configure a Standard Serial Port to enable communication over Bluetooth
link between instrument and PC. No code for pairing the devices is needed. Run the EurolinkPRO program. The PC and the instrument will automatically recognize each other. The instrument is prepared to communicate with the PC.

How to configure a Bluetooth link between instrument and Android device
Switch On the instrument. Some Android applications automatically carry out the setup of a Bluetooth
connection. It is preferred to use this option if it exists. This option is supported by Metrel’s Android applications. If this option is not supported by the selected Android application then configure a Bluetooth link via Android device’s Bluetooth configuration tool. No code for pairing the devices is needed. The instrument and Android device are ready to communicate.
Notes: Sometimes there will be a demand from the PC or Android device to enter the code. Enter code `NNNN’ to correctly configure the Bluetooth link. The name of correctly configured Bluetooth device must consist of the instrument type plus serial number, eg. MI 3125 BT-12240429I. If the Bluetooth module got another name, the configuration must be repeated. Model MI 3125 BT doesn’t support operation with Bluetooth dongle A 1436. In case of serious troubles with the Bluetooth communication it is possible to reinitialize the internal Bluetooth module. The initialization is carried out during the Initial settings procedure. In case of a successful initialization “INTERNAL BLUETOOTH SEARCHING OK!” is displayed at the end of the procedure. See chapter 4.2.7 Initial settings.

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Upgrading the instrument

7 Upgrading the instrument

The instrument can be upgraded from a PC via the RS232 communication port. This enables to keep the instrument up to date even if the standards or regulations change. The upgrade can be carried with help of a special upgrading software and the communication cable as shown on Figure 6.14. Please contact your dealer for more information.

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Maintenance

8 Maintenance

Unauthorized persons are not allowed to open the Eurotest Combo instrument. There are no user replaceable components inside the instrument, except the battery and fuse under rear cover.

8.1 Fuse replacement

There is a fuse under back cover of the Eurotest Combo instrument.

F1 M 0.315 A / 250 V, 205 mm This fuse protects internal circuitry for continuity functions if test probes are connected to the mains supply voltage by mistake during measurement.

Warnings:

Disconnect all measuring accessory and switch off the instrument

before opening battery / fuse compartment cover, hazardous voltage

inside!

Replace blown fuse with original type only, otherwise the instrument may

be damaged and/or operator’s safety impaired!

Position of fuse can be seen in Figure 3.4 in chapter 3.3 Back side.

8.2 Cleaning

No special maintenance is required for the housing. To clean the surface of the instrument use a soft cloth slightly moistened with soapy water or alcohol. Then leave the instrument to dry totally before use.

Warnings:
Do not use liquids based on petrol or hydrocarbons! Do not spill cleaning liquid over the instrument!

8.3 Periodic calibration

It is essential that the test instrument is regularly calibrated in order that the technical specification listed in this manual is guaranteed. We recommend an annual calibration. Only an authorized technical person can do the calibration. Please contact your dealer for further information.

8.4 Service

For repairs under warranty, or at any other time, please contact your distributor.

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Technical specifications

9 Technical specifications

9.1 Insulation resistance

Insulation resistance (nominal voltages 50 VDC, 100 VDC and 250 VDC)

Measuring range according to EN61557 is 0.15 M 199.9 M.

Measuring range (M)

Resolution (M)

Accuracy

0.00 19.99

0.01

(5 % of reading + 3 digits)

20.0 99.9 100.0 199.9

0.1

(10 % of reading) (20 % of reading)

Insulation resistance (nominal voltages 500 VDC and 1000 VDC)

Measuring range according to EN61557 is 0.15 M 1 G.

Measuring range (M)

Resolution (M)

Accuracy

0.00 19.99

0.01

(5 % of reading + 3 digits)

20.0 199.9

0.1

(5 % of reading)

200 999

1

(10 % of reading)

Voltage Measuring range (V) 0 1200

Resolution (V) 1

Accuracy (3 % of reading + 3 digits)

Nominal voltages ………………………….50 VDC, 100 VDC, 250 VDC, 500 VDC, 1000 VDC Open circuit voltage ………………………-0 % / +20 % of nominal voltage
Measuring current…………………………min. 1 mA at RN=UN1 k/V Short circuit current……………………… max. 3 mA The number of possible tests………… > 1200, with a fully charged battery Auto discharge after test.
Specified accuracy is valid if 3-wire test lead is used while it is valid up to 100 M if tip commander is used.
Specified accuracy is valid up to 100 M if relative humidity > 85 %. In case the instrument gets moistened, the results could be impaired. In such case, it is recommended to dry the instrument and accessories for at least 24 hours. The error in operating conditions could be at most the error for reference conditions
(specified in the manual for each function) 5 % of measured value.

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Technical specifications

9.2 Continuity

9.2.1 Resistance R LOW

Measuring range according to EN61557 is 0.16 1999 .

Measuring range R ()

Resolution ()

Accuracy

0.00 19.99

0.01

(3 % of reading + 3 digits)

20.0 199.9 200 999

0.1

1

(5 % of reading)

1000 1999

1

(10 % of reading)

Open-circuit voltage………………………6.5 VDC 9 VDC Measuring current…………………………min. 200 mA into load resistance of 2 Test lead compensation…………………up to 5 The number of possible tests …………> 2000, with a fully charged battery Automatic polarity reversal of the test voltage.
9.2.2 Resistance CONTINUITY

Measuring range () 0.0 19.9 20 1999

Resolution () 0.1 1

Accuracy (5 % of reading + 3 digits)

Open-circuit voltage………………………6.5 VDC 9 VDC Short-circuit current ………………………max. 8.5 mA Test lead compensation…………………up to 5

9.3 RCD testing

Note: All data (marked with “”) regarding B, B+ and EV type RCDs is valid for model MI 3125 BT only.
9.3.1 General data
Nominal residual current (A, F,AC) ….10 mA, 30 mA, 100 mA, 300 mA, 500 mA, 1000 mA
Nominal residual current (EV)…………30 mA a.c., 6 mA d.c. Nominal residual current accuracy…..-0 / +0.1I; I = IN, 2IN, 5IN
-0.1I / +0; I = 0.5IN AS / NZ selected: ± 5 % Test current shape……………………Sine-wave (AC, EV a.c.), pulsed (A, F), smooth DC (B, B+, EV d.c.)* DC offset for pulsed test current ……..< 2 mA (typical) RCD type …………………………………….(non-delayed), S (time-delayed), EV Test current starting polarity …………. 0 º or 180 º Voltage range ………………………………93 V 134 V (45 Hz 65 Hz) 185 V 266 V (45 Hz 65 Hz)

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Technical specifications

IN × 1/2

IN × 1

IN × 2

IN × 5

IN AC A,F B,B+ AC A,F B,B+ AC A,F B,B+* AC A,F

(mA)

10

5 3.5 5

10 20 20 20 40 40 50 100

30

15 10.5 15 30 42 60 60 84 120 150 212

100 50 35 50 100 141 200 200 282 400 500 707

300 150 105 150 300 424 600 600 848 ×

1500 ×

500 250 175 250 500 707 1000 1000 1410 ×

2500 ×

1000 500 350 500 1000 1410 ×

2000 × ×

n.a. ×

×…………………………………………………not applicable

…………………………………………………………… applicable

AC type……………………………………….sine wave test current

A, F types…… ……………………………..pulsed current

B, B+ types ……………………………….smooth DC current

RCD I B,B+ AC A,F B,B+

100

300

1000

×

×

×

×

IN × 1/2

IN × 1

IN × 1

IN × 2

IN × 5

(mA)

(mA)

(mA)

(mA)

(mA)

IN (mA) EV a.c.

EV a.c.

EV d.c.

EV a.c.

EV a.c.

30 a.c. 15

30

×

60

150

6 d.c. ×

×

6

×

×

×…………………………………………………not applicable

…………………………………………………………… applicable

EV type (a.c. part). ……………………….sine wave test current

EV type (d.c. part)…………………………smooth DC current

RCD I
EV a.c. ×

EV d.c. ×

9.3.2 Contact voltage RCD-Uc

Measuring range according to EN61557 is 20.0 V 31.0V for limit contact voltage 25V

Measuring range according to EN61557 is 20.0 V 62.0V for limit contact voltage 50V

Measuring range (V)

Resolution (V)

Accuracy

0.0 19.9

0.1

(-0 % / +15 %) of reading ± 10 digits

20.0 99.9

0.1

(-0 % / +15 %) of reading

The accuracy is valid if mains voltage is stabile during the measurement and PE

terminal is free of interfering voltages.

Test current ……………………………….. max. 0.5IN Limit contact voltage ……………………. 25 V, 50 V Specified accuracy is valid for complete operating range.

9.3.3 Trip-out time

Complete measurement range corresponds to EN 61557 requirements.

Maximum measuring times set according to selected reference for RCD testing.

Measuring range* (s)

Resolution (ms)

Accuracy

0.0 m 40.0 m

0.1

1 ms

40.1 m 999.9 m

0.1

3 ms

1.00 10.00

10

10 ms

• For max. time see normative references in 4.2.4 ­ this specification applies to max.

time >40 ms.

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Test current ……………………………….. ½IN, IN, 2IN, 5IN 5IN is not available for IN=1000 mA (RCD type AC) or IN 300 mA (RCD types A, F, B, B+).
2IN is not available for IN=1000 mA (RCD types A, F) or IN 300 mA (RCD types B, B+).
1IN is not available for IN=1000 mA (RCD types B, B+). Specified accuracy is valid for complete operating range.

9.3.4 Trip-out current

Trip-out current

Complete measurement range corresponds to EN 61557 requirements.

Measuring range I

Resolution I

Accuracy

0.2IN 1.1IN (AC, EV a.c. types)

0.05IN

0.1IN

0.2IN 1.5IN (A, F types, IN 30 mA)

0.05IN

0.1IN

0.2IN 2.2IN (A, F types, IN <30 mA)

0.05IN

0.1IN

0.2IN 2.2IN (B, B+ types)*

0.05IN

0.1IN

0.2IN 1.0IN (EV d.c. type)*

0.05IN

0.1IN

Trip-out time Measuring range (s) 0.0 m 999.9 m 1.00 10.00

Resolution (ms) 0.1 10

Accuracy 3 ms 10 ms

Contact voltage

Measuring range (V) Resolution (V)

Accuracy

0.0 19.9

0.1

(-0 % / +15 %) of reading 10 digits

20.0 99.9

0.1

(-0 % / +15 %) of reading

The accuracy is valid if mains voltage is stabile during the measurement and PE

terminal is free of interfering voltages.

Trip-out measurement is not available for IN=1000 mA (RCD types B, B+)*. Specified accuracy is valid for complete operating range.

9.4 Fault loop impedance and prospective fault current

9.4.1 No disconnecting device or FUSE selected

Fault loop impedance

Measuring range according to EN61557 is 0.25 9.99k.

Measuring range ()

Resolution ()

Accuracy

0.00 9.99 10.0 99.9

0.01 0.1

(5 % of reading + 5 digits)

100 999 1.00k 9.99k

1

10

10 % of reading

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Prospective fault current (calculated value)

Measuring range (A)

Resolution (A)

0.00 9.99

0.01

10.0 99.9

0.1

100 999

1

1.00k 9.99k

10

10.0k 23.0k

100

Accuracy
Consider accuracy of fault loop resistance measurement

The accuracy is valid if mains voltage is stabile during the measurement.

Test current (at 230 V) …………………. 6.5 A (10 ms) Nominal voltage range…………………..93 V 134 V (45 Hz 65 Hz)
185 V 266 V (45 Hz 65 Hz)

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9.4.2 RCD selected

Fault loop impedance

Measuring range according to EN61557 is 0.46 9.99 k for I test = “Std” and 0.48

9.99 k for I test = “Low”.

Measuring range Resolution

Accuracy

Accuracy

()

()

I test = “Std”

I test = “Low”

0.00 9.99

0.01

(5 % of reading + 10 (5 % of reading + 12

10.0 99.9

0.1

digits)

digits)

100 999 1.00k 9.99k

1 10

10 % of reading

10 % of reading

Accuracy may be impaired in case of heavy noise on mains voltage.

Prospective fault current (calculated value)

Measuring range (A)

Resolution (A)

0.00 9.99

0.01

10.0 99.9

0.1

100 999

1

1.00k 9.99k

10

10.0k 23.0k

100

Accuracy
Consider accuracy of fault loop resistance measurement

Nominal voltage range…………………..93 V 134 V (45 Hz 65 Hz) 185 V 266 V (45 Hz 65 Hz)
No trip out of RCD.

9.5 Line impedance and prospective short-circuit current / Voltage drop

Line impedance

Measuring range according to EN61557 is 0.25 9.99k.

Measuring range ()

Resolution ()

Accuracy

0.00 9.99 10.0 99.9

0.01

0.1

(5 % of reading + 5 digits)

100 999 1.00k 9.99k

1 10

10 % of reading

Prospective short-circuit current (calculated value)

Measuring range (A)

Resolution (A)

0.00 0.99

0.01

1.0 99.9

0.1

100 999

1

1.00k 99.99k

10

100k 199k

1000

Accuracy
Consider accuracy of line resistance measurement

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Test current (at 230 V) …………………. 6.5 A (10 ms) Nominal voltage range…………………..93 V 134 V (45 Hz 65 Hz)
185 V 266 V (45 Hz 65 Hz) 321 V 266 V (45 Hz 65 Hz)

Voltage drop (calculated value) Measuring range (%) 0.0 99.9

Resolution (%) 0.1

Accuracy Consider accuracy of line
impedance measurement(s)*

ZREF measuring range………………………0.00 20.0
*See chapter 5.6.2 Voltage drop for more information about calculation of voltage drop result.

9.6 Resistance to earth

Measuring range according to EN61557-5 is 2.00 9999 .

Measuring range ()

Resolution ()

Accuracy

0.00 19.99

0.01

20.0 199.9

0.1

(5% of reading + 5 digits)

200 9999

1

Max. auxiliary earth electrode resistance RC … 100RE or 50 k (whichever is lower) Max. probe resistance RP ………………………….. 100RE or 50 k (whichever is lower)
Additional probe resistance error at RCmax or RPmax. (10 % of reading + 10 digits)
Additional error at 3 V voltage noise (50 Hz) ………………………. (5 % of reading + 10 digits)
Open circuit voltage ………………………………….. < 15 VAC Short circuit current…………………………………… < 30 mA Test voltage frequency ……………………………… 125 Hz Test voltage shape …………………………………… sinusoidal Noise voltage indication threshold ………………. 1 V (< 50 , worst case)
Automatic measurement of auxiliary electrode resistance and probe resistance. Automatic measurement of voltage noise.

9.7 Voltage, frequency, and phase rotation

9.7.1 Phase rotation

Nominal system voltage range ……… 100 VAC 550 VAC Nominal frequency range……………… 14 Hz 500 Hz Result displayed …………………………. 1.2.3 or 3.2.1

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Technical specifications

9.7.2 Voltage

Measuring range (V) 0 550

Resolution (V) 1

Accuracy (2 % of reading + 2 digits)

Result type…………………………………. True r.m.s. (trms) Nominal frequency range……………… 0 Hz, 14 Hz 500 Hz

9.7.3 Frequency

Measuring range (Hz) 0.00 9.99 10.0 499.9

Resolution (Hz) 0.01 0.1

Accuracy (0.2 % of reading + 1 digit)

Nominal voltage range …………………. 10 V 550 V

9.7.4 Online terminal voltage monitor

Measuring range (V) 10 550

Resolution (V) 1

Accuracy (2 % of reading + 2 digits)

9.8 General data
Models MI 3125 and MI 3125 BT:
Power supply voltage…………………… 9 VDC (61.5 V battery or accu, size AA) Operation …………………………………… typical 20 h Charger socket input voltage ………… 12 V 10 % Charger socket input current ………… 400 mA max. Battery charging current ………………. 250 mA (internally regulated) Overvoltage category…………………… 600 V CAT III / 300 V CAT IV Plug commander
overvoltage category ……………. 300 V CAT II Protection classification ……………….. double insulation Pollution degree………………………….. 2 Protection degree ……………………….. IP 40
Display …………………………………….. 128×64 dots matrix display with backlight
Dimensions (w h d) ………………… 14 cm 8 cm 23 cm Weight …………………………………….. 1.0 kg, without battery cells
Reference conditions Reference temperature range……….. 10 C 30 C Reference humidity range…………….. 40 %RH 70 %RH
Operation conditions Working temperature range ………….. 0 C 40 C
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Technical specifications

Maximum relative humidity …………… 95 %RH (0 C 40 C), non-condensing
Storage conditions Temperature range ……………………… -10 C +70 C Maximum relative humidity …………… 90 %RH (-10 C +40 C)
80 %RH (40 C 60 C)
Model MI 3125 BT:

Communication transfer speed RS 232………………………………………. 115200 baud USB………………………………………….. 256000 baud
Memory size………………………………..1700 results

Bluetooth module: Class 2

The error in operating conditions could be at most the error for reference conditions (specified in the manual for each function) +1 % of measured value

• 1 digit, unless otherwise specified in the manual for particular function.

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Appendix A

A Appendix A – Fuse table

A.1 Fuse table – IPSC

Fuse type NV Rated current (A)
2 4 6 10 16 20 25 35 50 63 80 100 125 160 200 250 315 400 500 630 710 800 1000 1250

35m
32.5 65.6 102.8 165.8 206.9 276.8 361.3 618.1 919.2 1217.2 1567.2 2075.3 2826.3 3538.2 4555.5 6032.4 7766.8 10577.7 13619 19619.3 19712.3 25260.3 34402.1 45555.1

Disconnection time [s]

0.1

0.2

0.4

Min. prospective short- circuit current (A)

22.3

18.7

15.9

46.4

38.8

31.9

70

56.5

46.4

115.3

96.5

80.7

150.8

126.1

107.4

204.2

170.8

145.5

257.5

215.4

180.2

453.2

374

308.7

640

545

464.2

821.7

663.3

545

1133.1

964.9

836.5

1429

1195.4

1018

2006

1708.3

1454.8

2485.1

2042.1

1678.1

3488.5

2970.8

2529.9

4399.6

3615.3

2918.2

6066.6

4985.1

4096.4

7929.1

6632.9

5450.5

10933.5

8825.4

7515.7

14037.4

11534.9

9310.9

17766.9

14341.3

11996.9

20059.8

16192.1

13545.1

23555.5

19356.3

16192.1

36152.6

29182.1

24411.6

5
9.1 18.7 26.7 46.4 66.3 86.7 109.3 169.5 266.9 319.1 447.9 585.4 765.1 947.9 1354.5 1590.6 2272.9 2766.1 3952.7 4985.1 6423.2 7252.1 9146.2 13070.1

Fuse type gG Rated current (A)
2 4 6 10 13 16 20 25 32 35 40

35m
32.5 65.6 102.8 165.8 193.1 206.9 276.8 361.3 539.1 618.1 694.2

Disconnection time [s]

0.1

0.2

0.4

Min. prospective short- circuit current (A)

22.3

18.7

15.9

46.4

38.8

31.9

70

56.5

46.4

115.3

96.5

80.7

144.8

117.9

100

150.8

126.1

107.4

204.2

170.8

145.5

257.5

215.4

180.2

361.5

307.9

271.7

453.2

374

308.7

464.2

381.4

319.1

5
9.1 18.7 26.7 46.4 56.2 66.3 86.7 109.3 159.1 169.5 190.1

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Appendix A

50 63 80 100
Fuse type B Rated current (A) 6 10 13 15 16 20 25 32 40 50 63

919.2 1217.2 1567.2 2075.3

640 821.7 1133.1 1429

545 663.3 964.9 1195.4

464.2 545 836.5 1018

Disconnection time [s]

35m

0.1

0.2

0.4

Min. prospective short- circuit current (A)

30

30

30

30

50

50

50

50

65

65

65

65

75

75

75

75

80

80

80

80

100

100

100

100

125

125

125

125

160

160

160

160

200

200

200

200

250

250

250

250

315

315

315

315

266.9 319.1 447.9 585.4
5
30 50 65 75 80 100 125 160 200 250 315

Fuse type C Rated current (A)
0.5 1
1.6 2 4 6
10 13 15 16 20 25 32 40 50 63

35m
5 10 16 20 40 60 100 130 150 160 200 250 320 400 500 630

Disconnection time [s]

0.1

0.2

0.4

Min. prospective short- circuit current (A)

5

5

5

10

10

10

16

16

16

20

20

20

40

40

40

60

60

60

100

100

100

130

130

130

150

150

150

160

160

160

200

200

200

250

250

250

320

320

320

400

400

400

500

500

500

630

630

630

5
2.7 5.4 8.6 10.8 21.6 32.4 54 70.2 83 86.4 108 135 172.8 216 270 340.2

Fuse type K Rated current (A)
0.5 1

35m
7.5 15

Disconnection time [s]

0.1

0.2

0.4

Min. prospective short- circuit current (A)

7.5

7.5

7.5

15

15

15

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Appendix A

1.6 2 4 6 10 13 15 16 20 25 32
Fuse type D Rated current (A) 0.5 1 1.6 2 4 6 10 13 15 16 20 25 32

24

24

24

24

30

30

30

30

60

60

60

60

90

90

90

90

150

150

150

150

195

195

195

195

225

225

225

225

240

240

240

240

300

300

300

300

375

375

375

375

480

480

480

480

35m
10 20 32 40 80 120 200 260 300 320 400 500 640

Disconnection time [s]

0.1

0.2

0.4

Min. prospective short- circuit current (A)

10

10

10

20

20

20

32

32

32

40

40

40

80

80

80

120

120

120

200

200

200

260

260

260

300

300

300

320

320

320

400

400

400

500

500

500

640

640

640

5
2.7 5.4 8.6 10.8 21.6 32.4 54 70.2 81 86.4 108 135 172.8

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Appendix A

A.2 Fuse table ­ Impedances at 230 V a.c. (AS/NZS 3017)

Type B Rated current (A)
6 10 16 20 25 32 40 50 63 80 100 125 160 200
Type D Rated current (A)
6 10 16 20 25 32 40 50 63 80 100 125 160 200

Disconnection time [s] 0.4
Max. loop impedance () 9.6 5.8 3.6 2.9 2.3 1.8 1.4 1.2 0.9 0.7 0.6 0.5 0.4 0.3
Disconnection time [s] 0.4
Max. loop impedance () 3.1 1.8 1.2 0.9 0.7 0.6 0.5 0.4 0.3 0.2 0.2 0.1 0.1 0.1

Type C Rated current (A)
6 10 16 20 25 32 40 50 63 80 100 125 160 200
Fuse Rated current (A)
6 10 16 20 25 32 40 50 63 80 100 125 160 200

Disconnection time [s] 0.4
Max. loop impedance () 5.1 3.1 1.9 1.5 1.2 1.0 0.8 0.6 0.5 0.4 0.3 0.2 0.2 0.2

Disconnection time [s]

0.4

5

Max. loop impedance ()

11.5

15.3

6.4

9.2

3.1

5.0

2.1

3.6

1.6

2.7

1.3

2.2

1.0

1.6

0.7

1.3

0.6

0.9

0.4

0.7

0.3

0.5

0.2

0.4

0.2

0.3

0.1

0.2

All impedances are scaled with factor 1.00.

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Appendix B

B Appendix B – Accessories for specific measurements

The table below presents standard and optional accessories required for specific measurement. The accessories marked as optional may also be standard ones in some sets. Please see attached list of standard accessories for your set or contact your distributor for further information.

Function

Suitable accessories (Optional with ordering code A….)

Insulation resistance

Test lead, 3 x 1.5 m

Tip commander (A 1401)

R LOW resistance

Test lead, 3 x 1.5 m

Tip commander (A 1401)

Test lead, 4 m (A 1154)

Continuous resistance Test lead, 3 x 1.5 m

measurement

Tip commander (A 1401)

Test lead, 4 m (A 1154)

Line impedance

Test lead, 3 x 1.5 m

Mains measuring cable

Plug commander (A 1314)

Tip commander (A 1401)

Three-phase adapter (A 1110)

Three-phase adapter with switch (A 1111)

Fault loop impedance

Test lead, 3 x 1.5 m

Mains measuring cable

Plug commander (A 1314)

Tip commander (A 1401)

Three-phase adapter (A 1110)

Three-phase adapter with switch (A 1111)

RCD testing

Test lead, 3 x 1.5 m

Mains measuring cable

Plug commander (A 1314)

Three-phase adapter (A 1110)

Three-phase adapter with switch (A 1111)

Earth resistance

Test lead, 3 x 1.5 m

Earth test set, 3-wire, 20 m (S 2026)

Earth test set, 3-wire, 50 m (S 2027)

Phase sequence

Test lead, 3 x 1.5 m

Three-phase adapter (A 1110)

Three-phase adapter with switch (A 1111)

Voltage, frequency

Test lead, 3 x 1.5 m

Mains measuring cable

Plug commander (A 1314)

Tip commander (A 1401)

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Appendix C

C Appendix C ­ Country notes

This appendix C contains collection of minor modifications related to particular country requirements. Some of the modifications mean modified listed function characteristics related to main chapters and others are additional functions. Some minor modifications are related also to different requirements of the same market that are covered by various suppliers.

C.1 List of country modifications

The following table contains current list of applied modifications.

Country HUN
AT NO, DK, SW AUS / NZ

Related chapters 5.5, 5.6, C.2.1 Appendix A 5.4, 9.3, C.2.2 4.2, C.2.3 4.2, 4.2.5, 4.2.8, 5.5, 5.6, Appendix A

Modification type Appended
Appended Appended Appended

Note Added gR fuse type
Special G type RCD IT supply system AUS / NZ fuse table added

C.2 Modification issues
C.2.1 HUN modification ­ gR fuse types

Modifications of the chapter 5.5

Test parameters for fault loop impedance measurement

Test

Selection of fault loop impedance sub-function [Zloop, Zs rcd]

Fuse type

Selection of fuse type [—, gR, NV, gG, B, C, K, D]

Fuse I

Rated current of selected fuse

Fuse T

Maximum breaking time of selected fuse

Lim

Minimum short circuit current for selected fuse.

See Appendix A and Appendix C for reference fuse data.

Modifications of the chapter 5.6

Test parameters for line impedance measurement

Test

Selection of line impedance [Zline] or voltage drop [U] sub-function

FUSE type Selection of fuse type [—, gR, NV, gG, B, C, K, D]

FUSE I

Rated current of selected fuse

FUSE T

Maximum breaking time of selected fuse

Lim

Minimum short circuit current for selected fuse.

See Appendix A and Appendix C for reference fuse data.

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Appendix C

C.2.1.1 Modification of Appendix A

In addition to fuse data given in Appendix A gR fuses are added.

Fuse type gR Rated current (A)
2 4 6 10 13 16 20 25 32 35 40 50 63 80 100 125 160 200 250 315 400 500 630 710 800 1000 1250

35m
31.4 62.8 94.2 157 204 251 314 393 502 550 628 785 989 1256 1570 1963 2510 3140 3930 4950 6280 7850 9890 11150 12560 15700 19630

Disconnection time [s]

0.1

0.2

0.4

Min. prospective short- circuit current (A)

14

10

8

28

20

16

42

30

24

70

50

40

91

65

52

112

80

64

140

100

80

175

125

100

224

160

128

245

175

140

280

200

160

350

250

200

441

315

252

560

400

320

700

500

400

875

625

500

1120

800

640

1400

1000

800

1750

1250

1000

2210

1575

1260

2800

2000

1600

3500

2500

2000

4410

3150

2520

4970

3550

2840

5600

4000

3200

7000

5000

4000

8750

6250

5000

5
5 10 15 25 32.5 40 50 62.5 80 87.5 100 125 157.5 200 250 313 400 500 625 788 1000 1250 1575 1775 2000 2500 3130

C.2.2 AT modification – G type RCD
Modified is the following related to the mentioned in the chapter 5.4: – Added G type RCD, – Time limits are the same as for general type RCD, – Contact voltage is calculated the same as for general type RCD.
Modifications of the chapter 5.4

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Appendix C

Test parameters for RCD test and measurement

TEST RCD sub-function test [RCDt, RCD I, AUTO, Uc].

IN

Rated RCD residual current sensitivity IN, IN(DC), [6 mA,30/6 mA, 10 mA,

30 mA, 100 mA, 300 mA, 500 mA, 1000 mA].

type

RCD type [AC, A, F, B, B+, EV*] starting polarity [ , , , , , *],

selective S , general non-delayed , delayed G characteristic.

MUL Ulim

Multiplication factor for test current [½, 1, 2, 5 IN]. Conventional touch voltage limit [25 V, 50 V].

• Model MI 3125 BT

** EV RCD

Notes: Ulim can be selected in the Uc sub-function only. Selective (time delayed) RCDs and RCDs with (G) – time delayed characteristic demonstrate delayed response characteristics. They contain residual current integrating mechanism for generation of delayed trip out. However, contact voltage pre- test in the measuring procedure also influences the RCD and it takes a period to recover into idle state. Time delay of 30 s is inserted before performing trip-out test to recover S type RCD after pre-tests and time delay of 5 s is inserted for the same purpose for G type RCD. The a.c. part of EV RCDs is tested according to EN 61008 / EN 61009 as general (non-delayed) RCDs. The d.c. part of EV RCDs is tested with a DC test current. The Pass limit is between 0.5 and 1.0 IN(DC).
Modification of the chapter 5.4.1

RCD type

AC

, G

AC

S

A,F

, G

A,F

S

A,F

, G

A,F

S

EV a.c. part

B, B+

B, B+

S

Contact voltage Uc proportional to 1.05IN 21.05IN
1.41.05IN 21.41.05IN
21.05IN 221.05IN
1.05IN 21.05IN 221.05IN

Rated IN any
30 mA < 30 mA

All models

any Model MI 3125 BT

Table C.1: Relationship between Uc and IN

Technical specifications remain the same.

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Appendix C

C.2.3 NO, DK, SW modification ­ IT supply system
C.2.3.1 Modification of chapter 4.2
Different instrument options can be set in the SETTINGS menu, additional option is added:
Selection of power supply system.
C.2.3.2 New chapter
For selection of proper supply system, the chapter 4.2.9 is added. 4.2.9. Supply earthing system
In this menu the tested supply system can be selected.

Keys:
UP / DOWN TEST Function selector

Figure 4.9: Selection of supply system
Selects distribution supply system. Confirms selected system and exits to settings menu. Exits back to main function menu.

C.2.3.3 New appendix D for IT supply system

C.2.4 AUS / NZ modification ­ Fuse types according to AS/NZS 3017 Modifications of the chapter 4.2
ISC factor is replaced with Z factor.

Modifications of the chapter 4.2.5

Figure 4.1: Options in Settings menu

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C.2.4.1 Z Factor
In this menu the Z factor can be set.

Appendix C

Keys:
UP / DOWN TEST Function selectors

Figure 4.6: Selection of Z factor
Sets Z value. Confirms Z value. Exits back to main function menu.

The impedance limit values for different overcurrent protective devices depend on nominal voltage and are calculated using the Z factor. Z factor 1.00 is used for nominal voltage 230 V and Z factor 1.04 is used for nominal voltage 240 V.

Modifications of the chapter 4.2.8

The default setup is listed below:

Instrument setting Z factor RCD standards

Default value 1.00 AS/NZS 3017

Modifications of the chapter 5.5

Modified test parameters for fault loop impedance measurement

Fuse type

Selection of fuse type [—, FUSE, B, C, D]

Lim

High limit fault loop impedance value for selected fuse.

See Appendix A.2 for reference fuse data.

Figure 5.25: Examples of loop impedance measurement result
Displayed results: Z fault loop impedance Isc ……….. prospective fault current, Lim……….high limit fault loop impedance value.
Prospective fault current IPFC is calculated from measured impedance as follows:
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MI 3125 / BT EurotestCOMBO

I PFC

Z LPE

UN scaling _

factor

where:

Un

Nominal UL-PE voltage (see table below),

scalling_factor…… Correction factor for Isc (set to 1.00).

Un Input voltage range (L-PE) 110 V (93 V UL-PE 134 V) 230 V (185 V UL-PE 266 V)

Modifications of the chapter 5.6

Modified test parameters for line impedance measurement

Fuse type

Selection of fuse type [—, FUSE, B, C, D]

Lim

High limit line impedance value for selected fuse.

See Appendix A.2 for reference fuse data.

Appendix C

Line to neutral

Line to line

Figure 5.29: Examples of line impedance measurement result

Displayed results: Z line impedance Isc ……….. prospective short-circuit current Lim……….high limit line impedance value.

Prospective short circuit current IPFC is calculated from measured impedance as follows:

I PFC

Z L N (L)

UN scaling _

factor

where:

Un

Nominal UL-N or UL1-L2 voltage (see table below),

Scalling factor …… Correction factor for Isc (set to 1.00).

Un Input voltage range (L-N or L1-L2)

110 V

(93 V UL-N 134 V)

230 V

(185 V UL-N 266 V)

400 V

(321 V UL-L 485 V)

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Appendix D

D Appendix D – IT supply systems

In order for operator to be familiar enough with measurements in and their typical applications in IT supply system it is advisable to read Metrel handbook Measurements on IT power supply systems.
D.1 Standard references
EN 60364-4-41, EN 60364-6, EN 60364-7-710, BS 7671
D.2 Fundamentals
In IT systems live parts are insulated from earth or connected to earth through sufficiently high impedance.
L1

133 V

133 V 230 V
133 V

230 V L2

230 V L3

Optional high impedance

N IMD (Optional)

Figure D.1: General IT supply system with reference designations
Three phase star connection, optional delta connection. Optional neutral line. Single-phase connection is also possible. Various system voltages possible. One faulty connection of any line to PE is treated as first fault and is regular but it has to
be repaired as soon as possible.
Testing of IT supply system is slightly different to standard tests in TN / TT system.

D.3 Measurement guides
The user has to select the IT supply system in the instrument before testing it. The procedure for selecting the IT supply system is defined in chapter 4.2.9 Supply earthing system. Once the IT system is selected the instrument can be used immediately. The instrument keeps selected IT system when it is turned off. Displayed designations correspond to IT system, see figure D.1.

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Appendix D

MI 3125 / MI 3125 BT test functions and IT systems
The table below contains functions of the instrument including compatibility notes related to the IT system.

IT system functions Voltage Voltage Phase rotation RCD functions RCD – Uc RCD – Trip out Time t RCD – Tripping Current RCD ­ Automatic test Loop functions Fault Loop Impedance Fault Loop Prospective Short-circuit Current Line functions Line Impedance Line Prospective Short-circuit Current Continuity functions Insulation Resistance Earth resistance PE test probe

Note
Symbols modified for IT system, see figure D.2. For three phase system only, automatic detection. Partially applicable. Not applicable.
Applicable with bypassing the test current.
Not applicable.
Impedance ZL1-L2. ISC for rated UL1-L2. Independent of selected supply system. Independent of selected supply system. Independent of selected supply system. Active, but does not inhibit selected test if voltage is detected.

Voltage measurements

Figure D.2: Voltage measurements Displayed results for single phase system: U21……….Voltage between line conductors, U1pe……..Voltage between line 1 and protective conductor, U2pe……..Voltage between line 2 and protective conductor. Line impedance See chapter 5.6, the measurement is the same; only terminal voltage monitor indication corresponds to IT system.
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Appendix D

RCD testing
RCD testing is performed in the same way as in TN/TT system (See chapter 5.4), with the following exception:
– UC measurement is relevant only in case of first fault. Test circuit with bypassing principle should correspond to that on figure D.3.

Figure D.3: RCD testing in IT system with bypassing RC

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Appendix E

E Appendix E ­ Commanders (A 1314, A 1401)

E.1 Warnings related to safety
Measuring category of commanders: Plug commander A 1314 ………… 300 V CAT II Tip commander A 1401 (cap off, 18 mm tip) 1000 V CAT II / 600 V CAT II / 300 V CAT II (cap on, 4 mm tip)…1000 V CAT II / 600 V CAT III / 300 V CAT IV
Measuring category of commanders can be lower than protection category of the instrument.
If dangerous voltage is detected on the tested PE terminal, immediately stop all measurements, find and remove the fault!
When replacing battery cells or before opening the battery compartment cover, disconnect the measuring accessory from the instrument and installation.
Service, repairs or adjustment of instruments and accessories is only allowed to be carried out by a competent authorized personnel!

E.2 Battery
The commander uses two AAA size alkaline or rechargeable Ni-MH battery cells. Nominal operating time is at least 40 h and is declared for cells with nominal capacity of 850 mAh.
Notes: If the commander is not used for a long period of time, remove all batteries from the battery compartment. Alkaline or rechargeable Ni-MH batteries (size AA) can be used. Metrel recommends only using rechargeable batteries with a capacity of 800 mAh or above. Ensure that the battery cells are inserted correctly otherwise the commander will not operate and the batteries could be discharged.
E.3 Description of commanders

Figure E.1: Front side tip commander (A 1401)

MI 3125 / BT EurotestCOMBO

Appendix E

Figure E.2: Front side plug commander (A 1314)

Figure E.3: Back side

Legend:
1 TEST
2 LED 3 LED 4 LEDs
5 Function selector
6 MEM 7 BL 8 Lamp key 9 Battery cells 10 Battery cover 11 Cap

TEST

Starts measurements. Acts also as the PE touching electrode.

Left status RGB LED

Right status RGB LED

Lamp LEDs (Tip commander)

Selects test function.

Store / recall / clear tests in memory of instrument. Switches On / Off backlight on instrument Switches On / Off lamp (Tip commander) Size AAA, alkaline / rechargeable NiMH Battery compartment cover Removable CAT IV cap (Tip commander)

E.4 Operation of commanders

Both LED yellow
Right LED red Right LED green Left LED blinks blue

Warning! Dangerous voltage on the commander’s PE terminal! Fail indication Pass indication Commander is monitoring the input voltage

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Appendix E

Left LED orange

Voltage between any test terminals is higher than 50 V

Both LEDs blink red

Low battery

Both LEDs red and switch off Battery voltage too low for operation of commander

PE terminal test procedure
Connect commander to the instrument. Connect commander to the item to be tested (see figure E.4 and E.5). Touch PE test probe (the TEST key) on commander for at least one second. If PE terminal is connected to phase voltage both LEDs will light yellow, the
warning message on the instrument is displayed, instrument’s buzzer is activated, and further measurements are disabled in Zloop and RCD functions.

Figure E.4: Reversed L and PE conductors (application of plug commander)

Figure E.5: Reversed L and PE conductors (application of tip commander)
Reversed phase and protection conductors! The most dangerous situation!
90

References

• 📧metrel@metrel.si

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