GREISINGER GMH 3750 Precision Thermometer User Manual

: June 6, 2024
: GREISINGER

Table of Contents

GMH 3750 Precision Thermometer
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GMH 3750 Precision Thermometer

H49.0.02.6C-12

Precision thermometer
for Pt100 4-wire temperature probes

as of version 1.8

operating manual

GMH 3750

H49.0.02.6C-12
CONTENTS

User’s Guide GMH 3750

page 2 of 16

1 GENERAL NOTE ……………………………………………………………………………………………………………………………………3

2 SAFETY ………………………………………………………………………………………………………………………………………………….3

2.1 INTENDED USE…………………………………………………………………………………………………………………………………….3 2.2 SAFETY SIGNS AND SYMBOLS………………………………………………………………………………………………………………..3 2.3 SAFETY GUIDELINES…………………………………………………………………………………………………………………………….3

3 PRODUCT SPECIFICATION………………………………………………………………………………………………………………….4

3.1 SCOPE OF SUPPLY ………………………………………………………………………………………………………………………………..4 3.2 OPERATION AND MAINTENANCE ADVICE ………………………………………………………………………………………………..4

4 HANDLING …………………………………………………………………………………………………………………………………………….5

4.1 DISPLAY …………………………………………………………………………………………………………………………………………….5 4.2 BASIC OPERATION……………………………………………………………………………………………………………………………….5 4.3 CONNECTIONS …………………………………………………………………………………………………………………………………….5 4.4 POP-UP CLIP ………………………………………………………………………………………………………………………………………..6

5 START OPERATION………………………………………………………………………………………………………………………………7

6 CONFIGURATION …………………………………………………………………………………………………………………………………7

7 REMARKS TO SPECIAL FEATURES ……………………………………………………………………………………………………8

7.1 DISPLAY RESOLUTION………………………………………………………………………………………………………………………….8
7.2 AVERAGE FILTER (,,T.AUG”)………………………………………………………………………………………………………………..8 7.3 ALARM (,,AL.”) …………………………………………………………………………………………………………………………………..8 7.4 USER SENSOR CURVE (‘LIN USER’)………………………………………………………………………………………………………..9
7.5 REAL TIME CLOCK (,,CLOC”)……………………………………………………………………………………………………………….9

8 OPERATION OF LOGGER…………………………………………………………………………………………………………………….9

8.1 STORING SINGLE MEASUREMENTS (,,FUNC-STOR”) …………………………………………………………………………………9 8.2 AUTOMATIC RECORDING WITH SELECTABLE CYCLE TIME ,,FUNC CYCL”……………………………………………….10
9 OUTPUT ……………………………………………………………………………………………………………………………………………….11

9.1 SERIAL INTERFACE …………………………………………………………………………………………………………………………….11 9.2 ANALOGUE OUTPUT SCALING WITH DAC.0 AND DAC.1 ……………………………………………………………………..12
10 INPUT ADJUSTMENT……………………………………………………………………………………………………………………….12

10.1 ZERO DISPLACEMENT (‘OFFSET’)………………………………………………………………………………………………………12 10.2 SCALE CORRECTION (‘SCALE’)………………………………………………………………………………………………………….12 10.3 CALIBRATION SERVICES ………………………………………………………………………………………………………………….12

11 PROBE CONNECTION ……………………………………………………………………………………………………………………..12

11.1 4-WIRE CONNECTIONS……………………………………………………………………………………………………………………..12 11.2 2- OR 3-WIRE CONNECTIONS …………………………………………………………………………………………………………….12 11.3 4-POLIGER MINI DIN PLUG ………………………………………………………………………………………………………………13

12 SOME BASICS OF PRECISION TEMPERATURE MEASURING……………………………………………………..13

13 FAULT AND SYSTEM MESSAGES …………………………………………………………………………………………………..14

14 RESHIPMENT AND DISPOSAL ………………………………………………………………………………………………………..15

14.1 RESHIPMENT ………………………………………………………………………………………………………………………………….15 14.2 DISPOSAL INSTRUCTIONS…………………………………………………………………………………………………………………15

15 SPECIFICATIONS……………………………………………………………………………………………………………………………..16

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User’s Guide GMH 3750

page 3 of 16

1 General Note
Read this document carefully and get used to the operation of the device before you use it. Keep this document within easy reach near the device for consulting in case of doubt.

Mounting, start-up, operating, maintenance and removing from operation must be done by qualified, specially trained staff that have carefully read and understood this manual before starting any work.

The manufacturer will assume no liability or warranty in case of usage for other purpose than the intended one, ignoring this manual, operating by unqualified staff as well as unauthorized modifications to the device. The manufacturer is not liable for any costs or damages incurred at the user or third parties because of the usage or application of this device, in particular in case of improper use of the device, misuse or malfunction of the connection or of the device.

2 Safety
2.1 Intended Use
The GMH 3750 is a precision thermometer for the measurement of the temperature with exchangeable 4wire Pt100 temperature sensors. With high resolution and precision temperature values can be measured from -200 to 850 °C. The device is to be protected against wetness and soiling and has to be stored and operated only within the permissible environmental conditions and connection data (see “Specification”).
2.2 Safety signs and symbols
Warnings are labelled in this document with the followings signs:

Caution! This symbol warns of imminent danger, death, serious injuries and significant damage to property at nonobservance.
Attention! This symbol warns of possible dangers or dangerous situations which can provoke damage to the device or environment at non-observance.
Note! This symbol point out processes which can indirectly influence operation or provoke unforeseen reactions at non-observance.

2.3 Safety guidelines

This device has been designed and tested in accordance with the safety regulations for electronic devices. However, its trouble-free operation and reliability cannot be guaranteed unless the standard safety measures and special safety advises given in this manual will be adhered to when using the device.

1. Trouble-free operation and reliability of the device can only be guaranteed if the device is not subjected to any other climatic conditions than those stated under “Specification”. If the device is transported from a cold to a warm environment condensation may cause in a failure of the function. In such a case make sure the device temperature has adjusted to the ambient temperature before trying a new start-up.

DANGER

If there is a risk whatsoever involved in running it, the device has to be switched off immediately and to be marked accordingly to avoid re-starting. Operator safety may be a risk if: – there is visible damage to the device – the device is not working as specified – the device has been stored under unsuitable conditions for a longer time. In case of doubt, please return device to manufacturer for repair or maintenance.

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User’s Guide GMH 3750

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3. When connecting the device to other devices the connection has to be designed most thoroughly as internal connections in third-party devices (e.g. connection GND with protective earth) may lead to undesired voltage potentials that can lead to malfunctions or destroying of the device and the connected devices.

_DANGER
4.
_DANGER
5.
DANGER
6.

This device must not be run with a defective or damaged power supply unit. Danger to life due to electrical shock!
Do not use these products as safety or emergency stop devices or in any other application where failure of the product could result in personal injury or material damage. Failure to comply with these instructions could result in death or serious injury and material damage. This device must not be used at potentially explosive areas! The usage of this device at potentially explosive areas increases danger of deflagration, explosion or fire due to sparking.
This device is not constructed for use in medical applications.

DANGER
3 Product Specification
3.1 Scope of supply
The scope of supply includes:
device with 9V battery block Operation manual
3.2 Operation and maintenance advice
Battery operation If bAt’ is shown in the lower display the battery has been used up and needs to be replaced. However, the device will operate correctly for a certain time. IfbAt’ is shown in the upper display the voltage is too low to operate the device; the battery has been completely used up. The battery has to be taken out, when storing device above 50 °C. We recommend taking out battery if device is not used for a longer period of time. After recommissioning the real-time clock has to be set again.
· Mains Operation with power supply When using a power supply please note that operating voltage has to be 10.5 to 12 V DC. Do not apply overvoltage!! Cheap 12V-power supplies often have excessive no-load voltage. We, therefore, recommend using regulated voltage power supplies.
Trouble-free operation is guaranteed by our power supply GNG10/3000. Prior to connecting the power supply to the mains make sure that the operating voltage stated at the power supply is identical to the mains voltage.
Treat device and sensor carefully. Use only in accordance with above specification. (do not throw, hit against etc.). Protect plug and socket from soiling.
To disconnect temperatur sensor plug do not pull at the cable but at the plug. When connecting the probe the plug will slide in smoothly if plug is entered correctly.
Selection of Output-Mode: The output can be used as serial interface or as analogue output. This choice has to be done in the configuration menu.

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4 Handling
4.1 Display

User’s Guide GMH 3750

page 5 of 16

1 Maindisplay: Currently measured temperature 2 Secondary display: Display of min, max or hold values Special display elements: 3 Min/Max/Hold: shows if a min., max. or hold value is
displayed in the auxiliary display
4 “Offset” arrow: indicates that zero point offset is activated 5 ,,Corr” arrow: indicates that a scale correction is activated
6 ,,Logg” arrow: Shown if logger function is selected, flashes if cyclic logger is running
7 ,,Alarm” arrow: Flashes if alarm is present

4.2 Basic Operation

ON

Tara

OFF max

1

2

3

Set min Store

Menu

4

5

Quit
6

4.3 Connections

On / Off

min/max at measure:

press short:

press again:

shows the min./max. value hides min./max. value

press 2 sec.:

clears particular value

Tara Function only during configuration:

3

Selection of menu-parameter

Set/Menu: press short: Store/Quit: press short:
at active logger: at menu:

invokes configuration menu
hold-function, the last measuring value will be held in the secondary display. invokes logger functions acknowledge setting, return to measurement

Output:

Connection for el. Isolated interface adapter or for analog output (please refer to chapter 9)

Probe connection: 4 pole Mini-DIN-Socket, for Pt100 4-wire probes

Power supply: the mains adapter socket is located at the left side of the device.

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4.4 Pop-up clip

User’s Guide GMH 3750

page 6 of 16

Handling: · Pull at label “open” in order to swing open the pop-up clip. · Pull at label “open” again to swing open the pop-up clip further.

Pop-up clip closed

Pop-up clip at position 90° Pop-up clip at position 180°

Function:
· The device with a closed pop-up clip can be plainly laid onto a table or attached to a belt, etc. · The device with pop-up clip at position 90° can be set up on a table, etc. · The device with pop-up clip at position 180° can be suspended from a screw or the magnetic holder
GMH 1300.

Device attached to a belt

Device set up on a table

Device suspended from magnetic holder GMH 1300

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User’s Guide GMH 3750

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5 Start Operation

ON

Connect temperature probe, turn on device via

OFF
1

key.

After segment test

the device displays some configuration:

· If the logger function is not off, the time of the integrated clock will shortly be displayed. · If a zero point adjustment was carried out, the display shows shortly ,,nuLL Corr”.

After changing the battery the clock-setting menu is activated automatically (,CLOC`). Check the clock and adjust, if necessary (p.r.t. chapter 6).

After that, the device is ready for measuring.

6 Configuration

To change device settings, press Menu (key 4) for 2 seconds. This will call the configuration menu (main display: ,,SEt” or “rEAd LoGG”). Pressing key Menu changes between the menus, pressing ( (key 3) jumps to the referring parameters, which can be selected with key ( (key 3). The parameters can be changed with (key 2) or (key 5). Pressing Menu again jumps back to the main configuration menu and saves the settings. Quit (key 6) finishes the configuration and returns to standard measuring operation.

Menu(*1) ,Menu`

Parameter/Values(2*)

Meaning

or

Read Logg: single value-logger read out

(Only when data existing! Please refer to chapter 12)

p.r.t. 8

Set Configuration: Generic Settings

°C:

All temperature values are in degrees Celsius

°F:

All temperature values are in degrees Fahrenheit

0.1° / 0.01°:

Resolution 0.1° / 0.01°

7.1

Auto:

Resolution is selected automatically

E.751

characteristic curve according to EN60751

7.4

USEr

User sensor curve (Predefined to EN60751 values,

changeable by software GMHKonfig)

-2.50…2.50°C / Zero correction

10.1

-4.50…4.50°F

oFF:

Zero displacement inactive (=0.0°)

-2.000…2.000: Scale correction [in %]

10.2

oFF:

Scale correction factor inactive (=0.000)

1…30: oFF:

Average filter (period in seconds) Average filter inactive

7.2

1…120
oFF oFF: SEr: dAC: 01,11..91

Power-off delay in minutes. Device will be

automatically switched off as soon as this time has

elapsed if no key is pressed or no interface

communication takes place

Power-off function inactive (continuous operation)

No output function

9

Output is serial interface

Output is analogue output

Base address of device for interface communication

9.1

-200..850°C / Zero point of analogue output: Temperature at

9.2

328…1562°F which the analogue output potential should be 0V

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-200..850°C / -328…1562°F

User’s Guide GMH 3750

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Scale of analogue output : Temperature value at

9.2

which the analogue output potential should be 1V

Set Alarm: Setting of Alarm Function

On / No.So

Alarm on with horn-sound / Alarm on without horn-

7.3

sound

OFF

no alarm function

-200°C …AL.Hi Min alarm rail (not when AL. oFF)

AL.Lo … 850°C Max alarm rail (not when AL. oFF)

Set Logger: Setting of Logger Function

CYCL

Cyclic: logger function cyclic logger

Stor

Store: logger function individual value logger

OFF

No logger function

0:01… 60:00

Cycle time of cyclic logger [minutes:seconds]

Set Clock: Einstellen der Echtzeituhr

HH:MM

Clock: Setting of time hours:minutes

YYYY

Year

8 * 8
7.4

TT.MM

Date: day.month

(*) Hint:

If the logger memory contains data already, the menus/parameters marked with (*) can not be invoked! If these should be altered the logger has to be stopped and the memory has to be cleared before!
Restoring of ex-works settings The settings will be set to the settings ex works, if keys Set and Store are pressed simultaneously for more than 2 seconds.

7 Remarks To Special Features

7.1 Display Resolution
Standard setting: ‘Auto’, i.e. the device automatically switches over to the optimum resolution between .01° and 0.01°. If temperatures to be measured are near the switching threshold, a fixed resolution may be better, e.g. for easy manual recording. In such a case please set the optimum resolution to the desired value.
7.2 Average filter (,,t.AuG”)
The filter forms the arithmetic floating average over the entered time. The displayed value will be correspondingly slower in this case.
7.3 Alarm (,,AL.”)
There are three possible settings: Alarm off (AL. oFF), on with horn sound (AL. on), on without horn sound (AL. no.So). Following conditions will display an alarm, when the function is activated (on or no.So): – Value is below lower (AL. Lo) or above upper alarm rail (AL.Hi). – Sensor error – Low battery (bAt) – Err.7: System error (always with sound) In case of an alarm and when polling the interface the “prio”-flag is set in the returned message.

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User’s Guide GMH 3750

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7.4 User Sensor Curve (‘Lin USEr’)

By means of this function besides the standard conversion of resistance to temperature following EN60751(Lin E.751) also other curves can be used. The user sensor curve can be read and edited by the configuration software GMHKonfig. The standard setting ex works is also set to the EN60751 data. The curve is defined by a table with two columns (input resistance [Ohm]/output temperature [°C]) with 50 rows. Info: the sensor curve following EN60751 uses the international temperature scale ITS90 and following formulas:

Temperatures < 0°C:

Rneg(T) := 100 · [1 + 3.9083·10-3·T 5.775·10-7·T2 4.183·10-12·(T 100)·T3]

Temperatures >= 0°C:

Rpos(T) := 100 · (1 + 3.9083·10-3·T 5.775·10-7·T2)

Please notice: Temperature measurements with the user sensor curve are allowed only within the temperature range, which has been used to generate the user sensor curve. Measuring with activated user sensor curve beyond the checked temperature range may lead to larger errors. Therefore the sensor curve acc. to EN 60751 (Lin E.751) has to be used for temperature measurements beyond the checked temperature range.

7.5 Real Time Clock (,,CLOC”)
The real time clock is used for the logger function: Recorded values are also containing the point of time, when they were measured. Please check the settings when necessary. If the battery was replaced the referring menu ,CLOC` will automatically be started

8 Operation Of Logger

The device supports two different logger functions: ,,Func-Stor”: manual recording via keypress “Store” (key 6). ,,Func-CYCL”: automatic recording with the selected recording interval/cycle
The logger records 1 measurement result each time
The data set consists of: – measuring value at time of recording
– time and date of recording
For the read out and evaluation of the data the software GSOFT3050 (V1.7 or higher) has to be used. The software also allows easy configuration and starting of the logger.
When the logger is activated (Func Stor or Func CYCL) the hold function is no longer available, key 6 is solely used for the operation of the logger functions.

8.1 Storing Single Measurements (,,Func-Stor”)
a) Record Measuring:
If the logger function “Func Stor” was activated (see chapter 6″Configuration”), up to 99 measuring data sets can be recorded manually.
Press shortly: Data set will be recorded (“St. XX” will be shown shortly. XX is the number of the data set)

If the logger memory is full, the display will show: b) Viewing Recorded Measurings:
Stored data sets can be either read out via PC Software GSOFT3050, or be viewed in the display directly. Press for 2 seconds: The display will show:

Please note: “rEAd Logg” only appears, if there are already data stored! If memory is empty, the

configuration menu

will show.

Press shortly: Changing between measuring value and date+time of data set

or

Changing between the data sets

Exit logger data display

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c) Clear recorded measurings:

If there are already data sets stored, these can be deleted via the store key:

Press for 2 seconds: Calling of clear-Menu

Change selection by:

or

:

Clear nothing (cancel menu)

Clear all recordings

Clear the last recording

Stores the settings

8.2 Automatic Recording With Selectable Cycle Time ,,Func CYCL”
If the logger function “Func CYCL” was activated (see chapter 6 “Configuration”), and the logger was started, it automatically records data sets at intervals of the selected logger cycle time The logger cycle time is selectable from 1s to 60min (see chapter 6 “Configuration”).

Max. number of measurings:

16384

a) Starting a recording:

press for 2 seconds: the recording will be started.

Each recodring is signales with a short diplay of `St.XXXXX’. XX is the number of the data set. If the logger memory is full, the display will show b) Stop the recording:
Press for 2 seconds: If a recording is running, the Stop menu will be shown

Change selection by:

or

:

Do not stop the recording

Stop the recording

Stores the settings

Note:

If you try to switch off the instrument in the cyclic recording operation, You will be asked automatically if the recording should be stopped. The device can only be switched off after the recording has been stopped! The Auto-Power-Off- function is deactivated during recording!

c) Clear recorded measurings:

Press for 2 seconds: If logger data are present and the recording was stopped, the clear menu will be shown

Change selection by:

or

:

Clear nothing (cancel menu)

Clear all recordings

Stores the settings

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User’s Guide GMH 3750

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9 Output

The output can be used as serial interface (for USB 3100, USB 3100 N, GRS 3100 or GRS 3105 interface adapters) or as analogue output (0-1V). If none of both is needed, we suggest to switch the output off, because battery life then is extended.

9.1 Serial Interface

By means of the serial interface and a suitable electrically isolated interface adapter (USB 3100, USB 3100 N, GRS 3100 or GRS 3105) the device can be connected to a computer for data transfer. With the GRS 3105 up to 5 devices of the GMH3xxx- series can be connected to one interface (see also manual of GRS 3105). As a precondition the base addresses of all devices must not be identical, make sure to configure the base addresses accordingly (refer menu point “Adr.” in chapter 6). To avoid transmission errors, there are several security checks implemented e.g. CRC.

The following standard software packages are available for data transfer:

GSOFT3050:

Operating and evaluation software for instruments with integrated logger function

EBS20M/ -60M: 20- / 60-channel software to record and display the measuring values

GMHKonfig:

Software for a comfortable configuration of the device (e.g. freeware)

In case you want to develop your own software we offer a GMH3000-development package including

– an universally applicable 32bit Windows functions library (‘GMH3000.DLL’) with documentation that can

be used by all ‘serious’ programming languages.

– Programming examples for Visual Studio 2010 (C#, C++), Visual Basic 6.0TM, Delphi 1.0TM, TestpointTM,

LabviewTM

In addition to the operation at a PC the device can be operated with the GAM3000-device, to use the alarm function for simple supervision and controlling applications. Just connect a GAM3000 to the interface, activate the alarm function of the GMH and the relays output is operating.

Supported interface functions:

code 0 3 6 7 12 22 23 32

name / function Read nominal values Read system status Read min. values Read max values Read ID-no Read min. alarm rail Read max. alarm rail Read configuration flag Alarm function: 1, Alarm horn: 3 BitLoggerOn: 50, BitCyclicLogger: 51

102 Set min. alarm rail 103 Set max. alarm rail 160 Set configuration flag (see 32) 174 Delete min. value 175 Delete max. value 176 Read min. measuring range 177 Read max. measuring range 178 Read measuring range unit 179 Read measuring range decimal point 180 Read measuring type 194 Set display unit 199 Read measuring type in display 200 Read min. display range

code 201 202 204 208 214 215 216 217 222 223 224 225 226 227 228 229 231 233 234 236 240 254 260

name / function Read max. display range Read unit of display Read decimal point of display Read channel count Read scale correction Set scale correction Read zero displacement Set zero displacement Read power off time Set power off time Logger: read data cyclic logger Logger: read cycle time (LoGG – CYCL) Logger: set cycle time (LoGG – CYCL) Logger: start recording Logger: read # of data Logger: read status Logger: read stop time Read real time clock (CLOC) Set real time clock (CLOC) Read logger memory size Reset Read program identification Logger: read data manual logger

Note: The measuring and display range values read via interface are always in the selected display unit (°C/°F)!

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9.2 Analogue Output Scaling with DAC.0 and DAC.1

Note: Analogue output can not be used during logger recordings

With the DAC.0 and DAC.1 values the output can be rapidly scaled to your efforts. Keep in mind not to connect low-resistive loads to the output, otherwise the output value will be wrong and battery life is decreased. Loads above ca 10kOhm are uncritical. If the display exceeds the value set by DAC.1, then the device will apply 1V to the output If the display falls below the value set by DAC.0, then the device will apply 0V to the output In case of an error (Err.1, Err.2, no sensor, etc.) the device will apply slightly above 1V to the output.

plug wiring:

GND +Uout

Attention! the 3rd contact has to be left floating! Only stereo plugs are allowed!

10 Input Adjustment

10.1 Zero Displacement (‘Offset’)
The zero displacement is used to adjust the measuring display for probe deviations. temperature displayed = temperature measured – offset
Standard setting: ‘off’ = 0.0°, i.e. no zero displacement will be carried out. Together with the scale correction (see below) this factor is mainly used to compensate for sensor deviations. Unless the factor is set to ‘off’, the offset arrow in the display shows an active zero displacement.)
10.2 Scale Correction (‘Scale’)
The scale correction is used to adjust the measuring display for probe deviations. (factor is in %): displayed temperature[°C] = measured temperature[°C] (1+Scal/100)
or: displayed temperature[°F] = (measured temperature [°F]-32°F) (1+Scal/100) + 32°F Standard setting: ‘off’ =0.000, i.e. temperature is not corrected. Unless the factor is set to ‘off’, the Corr arrow in the display shows an active scale correction.)
*) The standard curve (Lin E.751) and the user sensor curve (Lin USEr) possess separate correction settings.
10.3 Calibration Services
Calibration certificates DKD-certificates other certificates: If device should be certificated for its accuracy, it is the best solution to return it to the manufacturer. Only the manufacturer is capable to do efficient recalibration if necessary to get results of highest accuracy!

11 Probe Connection
11.1 4-wire connections
The device is constructed and optimised for the connection of a Pt100 4-wire probe via 4 pole Mini-Din connectors.
4-wire connection

Figure shows upon probe jack pins
11.2 2- or 3-wire connections
It is also possible to connect a 3- or 2-wire probe to the device. Please observe that in consequence of the cable and contact resistance an increased measuring fault will occur.

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The connection of these probes should be carried out as follows:

3-wire connection

2-wire connection

Pt100

11.3 4-pole Mini DIN plug

It is also possible to attach a 4-pin mini-DIN plug with lock for self- assembly. Article: MINIDIN 4S.

12 Some Basics Of Precision Temperature Measuring

Probe Precision/Device Precision

The device is very precise (please refer to technical data).

To be able to use this high precision, the connected temperature probe has to be as precise as possible, too.

The following precision classes are available as a standard at reasonable prices (Platinum resistor

thermometers according to EN60751):

Tolerance class Norm

max. deviation in Kelvin

B

IEC 751 / EN 60751 ± (0,30 + 0,00500 · |temperature|)

A

IEC 751 / EN 60751 ± (0,15 + 0,00200 · |temperature|)

AA (= 1/3 B)

IEC 751 / EN 60751 ± (0,10 + 0,00167 · |temperature|)

1/10 B (= 1/10 B) none

± (0,03 + 0,00050 · |temperature|)

The range of validity depends on the design of the sensor. Wire wound sensors allow wider temperature ranges than economic thin film sensors (further restrictions may result from product-specific properties, such as cables or connection technology)

Tolerance class wire wound

B

-196 to +600 °C

A

-100 to +450 °C

AA (= 1/3 B)

-50 to +250 °C

1/10 B (= 1/10 B)

thin film -50 to +500 °C -30 to +300 °C 0 to +150 °C -50 to 100 °C

Error band for Pt 100 thin film sensors:

Error band for wire wound Pt 100 sensors:

For applications demanding higher precision than given by these classes we suggest to adjust the device to the used probe or to get a DAkkS or ISO calibration certificate for the device combined with the probe. Attention: if an adjusted or calibrated probe is replaced, also the adjustment or calibration certificate has to
be renewed to maintain the referring overall precision! Be careful when buying third party temperature probes: Besides the standard EN 60751 there are some other obsolete or unusual standards on the market. If such a probe has to be connected, the user sensor curve (have a look to the referring chapter) can be used to adjust the instrument!

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4-Wire-Measuring
When using resistance thermometers as the Pt100 a quite large measuring error can be caused by inadequate cables and connections. Using 4wire measuring avoids this kinds of errors mainly caused by unwanted resistances. It is suggested to use suitable probes and extensions only.

Heat loss caused by probe construction:
Especially when measuring temperatures which deviate very much from the ambient temperature, measuring errors often occur if the heat loss caused by the probe is not considered. When measuring fluids therefore the probe should be emerged sufficiently deep and be stirred continuously. When measuring gases the probe should also emerge as deep as possible in the gas to be measured (e.g. when measuring in channel/pipes) and the gas should flow around the probe at sufficient flow.

Measuring surface temperature
If temperature of the surface of an object has to be measured, one should pay attention especially when measuring hot (or very cold) surfaces, that the ambient air cools (or heats) the surface. Additionally the object will be cooled (or heated) by the probe or the probe can have a better heat flow to the ambient temperature as to the objects surface. Therefore specially designed surface probes should be used. The measuring precision depends mainly on he construction of the probe and of the physics of the surface itself. If selecting a probe try to choose one with low mass and heat flow from sensor to handle. Thermally conductive paste can increase the precision in some cases.

Allowable temperature range of probes
Pt100 Sensors are defined over a wide temperature range. Depending on probe materials and sort of sensor (e.g. hybrid sensors, wire wound resistors…) the allowable temperature ranges have to be considered. Exceeding the ranges at least causes a wrong measuring, it may even damage the probe permanently! Often it also has to be considered, that the temperature range is just valid for the probe tube, (plastic-) handles can’t stand the same high temperatures. Therefore, the tube length should be selected long enough, that temperature keeps low at the handle.

Self-heating
The measuring current of the instrument is just 0.3mA. The resulting in practice sensor heating even small sensor elements can be neglected.

Cooling by evaporation
When measuring air temperature the probe has to be dry. Otherwise, the cooling due to the evaporation causes too low measuring.

13 Fault and System Messages

Display

Meaning Low battery voltage, device will continue to work for a short time If mains operation: wrong voltage

Low battery voltage If mains operation: wrong voltage

Remedy Replace battery
Check/replace power supply, if fault continues to exist: device damaged Replace battery Check/replace power supply, if fault continues to exist device damaged

No display Or
Weird display

Low battery voltage If mains operation: wrong voltage

System error Device does not react on keypress Device defective

—-

Sensor error, no sensor connected

Sensor/cable or device defective

Err.1

Value exceeding measuring range

Err.2

Wrong probe connected Sensor/cable defective Value below display range

Err.3 Err.4 Err.7

Wrong probe connected Sensor/cable defective Value exceeding display range Value below display range System error

Replace battery Check/replace power supply, if fault continues to exist device damaged Disconnect battery or power supply, wait some time, re-connect Return to manufacturer for repair Connect sensor to socket Return to manufacturer for repair Check: Is the value exceeding the measuring range? Temperature too high! Check probe Replace Check: Is the value below the measuring range? Temperature too low! Check probe Replace Set resolution to 0.1° or Auto Set resolution to 0.1° or Auto Return to manufacturer for repair

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14 Reshipment and Disposal

14.1 Reshipment
All devices returned to the manufacturer have to be free of any residual of measuring media and other hazardous substances. Measuring residuals at housing or sensor may be a risk for persons or environment

Use an adequate transport package for reshipment, especially for fully functional devices. Please make sure that the device is protected in the package by enough packing materials.
14.2 Disposal instructions
Batteries must not be disposed in the regular domestic waste but at the designated collecting points.
The device must not be disposed in the unsorted municipal waste! Send the device directly to us (sufficiently stamped), if it should be disposed. We will dispose the device appropriate and environmentally sound.

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15 Specifications

Supported probes Sensor Curve Probe connection Resolution Measuring Ranges

Pt100 4-wires (2-wire possible)

according to EN60751 or with user-sensor curve (table of 50 rows)

4-pole Mini-DIN socket

0.01°C

0.1°C

0.01°F

0.1°F

-199.99…199.99 -200.0…850.0

-199.99…199.99 -328.0…1562.0

Precision Device without probe ±1Digit (at nominal temperature)

Range 0.01°C/F ±0.03 °C / ±0.06 °F

Range 0.1°C/F ±0.1 °C / ±0.2 °F

Measuring

4-wire measuring with thermo-voltage compensation, measuring current 0.3 mA

Measuring rate:

2 measurements per second

Temperature influence <= 0.002 K per 1K

Nominal temperature 25 °C

Ambient condition -25 … +50 °C (-13 … +122 °F), 0 to 95 %RH (not condensing)

Storage temperature -25 … +70 °C (-13…158 °F)

Output: serial interface: analog output:

3.5 mm audio plug, stereo output configurable to serial interface or to analog output
via optically isolated interface adapter USB 3100, USB 3100 N, GRS 3100 or GRS 3105 (accessory) connectable to PCs with USB- or RS232-interfaces.
0..1V, freely scalable (resolution 13 bit,accuracy 0.05% at nominal temperature), cap. load < 1 nF

Power Supply:

9V-Battery (included) as well as additional d.c. connector (diameter of internal pin 1.9 mm) for external 10.5-12V direct voltage supply. (Suitable power supply: GNG10/3000)

Power Consumption Output off

approx. 0.90 mA

Output = serial interface approx. 1.15 mA

Analog output

approx. 1.25 mA

Display: Pushbuttons:

Two 4 ½ digits LCD’s (12.4mm and 7 mm high), additional segments 6 membrane keys

Min-/Max-Memory Both the max. and the min. value will be memorised.

Holdfunction

Press button to store current value.

Automatic-Off-Function Device will be automatically switched off if not operated for longer time (adjustable

from 1 … 120 min)

Min/Max-Alarm

The measuring value is constantly monitored for the min and max rails. Alarming is done by integrated horn, display and interface

Real time clock

integrated clock with date and year

Logger

2 Functions: individual value logger (,,Stor”) and cyclic logger (,,Cycl)

Memory

Stor: 99; Cycl: 16384

Cycle-time CYCL 0:01 … 60:00 (minutes/seconds, min 1s, max 1h)

Housing:
Dimensions: Weight:

impact-resistant ABS plastic housing, membrane keyboard, transparent panel. Front side IP65, integrated pop-up clip for table top or suspended use. 142 x 71 x 26 mm (L x B x D) approx. 155 g

Directives / standards: The instruments confirm to following European Directives: 2014/30/EU EMC Directive 2011/65/EU RoHS
Applied harmonized standards: EN 61326-1 : 2013 emissions level: class B, emi immunity acc. to table 3 and A.1 Additional fault: <1% EN 50581 : 2012