Mastercool 52240-A Digital Clamp Meter Instruction Manual
- June 1, 2024
- Mastercool
Table of Contents
Mastercool 52240-A Digital Clamp Meter
Product Usage Instructions
AC Current Measurement
-
This Clamp Meter measures the average value of an AC signal and
displays it as an equivalent RMS value for a sine wave. -
Press the trigger to open the transformer jaw and clamp one conductor to be measured.
-
Read the AC value on the LCD.
-
To hold the display value, push the DATA HOLD switch before removing the transformer jaws.
AC/DC Voltage Measurement
- Set Function/Range Switch to desired V~ or V range.
- Insert the red test probe to the + input jack and the black test probe to the – input jack.
- Connect test probes in parallel to the circuit being measured.
- Read the voltage value on the LCD.
- To hold the display value, push the DATA HOLD switch before disconnecting the probes.
Resistance Measurement
- Set Function/Range Switch to the desired range.
- Insert the red/black test probes into the + and – input jacks respectively.
- Connect the test probes to the circuit being measured and read the resistance value on the LCD.
- WARNING: Before taking any in-circuit resistance measurement, remove power from the circuit being tested and discharge all capacitors.
Diode Tests
- Set Function/Range Switch to range.
- Insert the red test probe into the + input jack and the black test probe into the – input jack.
FAQ
- Q: How do I replace the battery?
- A: The battery cover allows for easy replacement of the battery. Simply remove the cover and replace it with a new battery following the correct polarity.
- Q: What does the PEAK HOLD function do?
- A: The PEAK HOLD function holds the maximum RMS value of current or voltage surge while a motor is starting, allowing for accurate measurements during startup.
FEATURES
- AC current: 10mA to 600A
- AC voltage: 100mV to 600V
- DC voltage: 1V to 600V
- Resistance: 100mΩ to 20KΩ
- Frequency count: 10Hz to 2KHz
- Continuity check: < 100Ω with audio tone
- Diode check: check forward or reverse
- With DATA HOLD & PEAK HOLD functions
- Unit & sign display
-
Transformer Jaws: Measures the AC current flowing through the conductor.
-
PEAK HOLD: A push button (push ON, OFF, ON: LCDs ( sign). The peak detector holds the maximum RMS value of Current or Voltage surge while a motor is starting.
-
Trigger: Press the lever to open the transformer jaws.
When the pressure lever is released, the jaws will close again. -
Display: 3 1/2 digit (1999 count), unit and sign display.
-
V, Hz, “ ”. Input Connector: High (+) and Low (-) input jack for all voltage, resistance, frequency, continuity, and diode measurements.
-
Drop-Preventing Wrist Strap:
Prevents the instrument from slipping off the hand while in use. -
Rotary Switch: A rotary switch is used to select the measurement function, Range, and Power (ON/OFF) switch.
-
DATA HOLD: A push button, (Push ON, OFF, ON: LCDs ( sign). Holds the reading on the LCD (for all functions and ranges.)
-
Battery Cover: Replacement battery
OPERATING INSTRUCTIONS
AC Current Measurement
This Clamp Meter measures the average value of an AC signal and displays it as
an equivalent RMS value for a sine wave. The measurement errors are introduced
when the input wave form is distorted (non-sinusoidal). The amount of errors
depends upon the amount of distortion. (FIGURE 1) shows the relationship
between sine, square, and triangular waveforms and the required conversion
factors.
- Set Function/Range switch to desired A~range. (20Ã or 200 Ãor 600 Ã)
- Press the trigger to open the transformer jaw and clamp one conductor to be measured. (FIGURE 2).
- Read the AC value on the LCD.
- If you want to hold the display value, push the DATA HOLD switch before removing the transformer jaws from the conductor.
AC/DC Voltage Measurement
- Set Function/Range Switch to desired V~ or V “ ” range.
- Insert the red test probe to the “ + ” input jack and the black test probe to the “ – ” input jack.
- Connect test prods of test probes IN PARALLEL to the circuit being measured.
- Read the voltage value on the LCD.
- If you want to hold the display value, push the DATA HOLD switch before disconnecting the probes from the measuring points.
Resistance Measurement
- Set Function/Range Switch to the desired range.
- Insert the red/black test probes into the “ + ” and “ – ” input jacks respectively.
- Connect the test probes to the circuit being measured and read the resistance value on the LCD.
WARNING: Before taking any in-circuit resistance measurement, remove power from the circuit being tested and discharge all capacitors.
Diode Tests (“ ”)
- Set Function/Range Switch to “ ” range.
- Insert the red test probe to the “ + ” input jack and the black test probe to the “ – ” input jack.
- Connect the Red test probe to the anode side and the Black test probe to the cathode side of the diode being tested.
- Read forward voltage (Vf) Value on LCD.
- Connect the test probe to the diode, opposite of step 3. The digital display value should be over range (1). This can be used for distinguishing the anode and cathode poles of a diode.
WARNING: Before taking any in-circuit measurement remove power from the circuit being tested and discharge all capacitors in the circuit.
Continuity Measurements “ ”
- Set Function/Range Switch to “ ” position.
- Insert the red/black test probes into the “+” and “-” input jacks.
- Connect the test probes to the circuit being measured.
- When the impedance on the circuit is below 100, a continuous beep will sound.
Frequency Measurement (Hz)
- Set Function/Range Switch to 2 KHz Range.
- Insert the red/black test probes into the “+” and “-” input jacks.
- Connect the test probes to the circuit being measured.
- Read the frequency value (Hz) on the LCD.
Peak Detect Measurement
- Set Function/Range Switch to desired A ~ or V ~ range.
- Set the Clamp Meter into the “PEAK HOLD” mode by pushing the “PEAK HOLD” Switch. The LCD will indicate “P” when the Peak Detect mode is measured.
- Follow this procedure for AC voltage and Current measurement. The displayed reading is the maximum RMS value of a surge in current or a Voltage pulse. The reading decays at the rate of about 1 digi/second.
GENERAL SPECIFICATIONS
- Display: 3-1/2 digit LCD (1999 count) with P (Peak Hold), H (Data Hold), “–” “BT” (Low Battery), “~” “V” “A” “Ω” “KΩ” “KHz” and decimal annunciators
- Sampling rate: 2.5 times per second
- Diameter of conductor: 40 mm max
- Polarity: Automatic “–” negative polarity indication
- Range selection: all ranges are measured by single range switch operation
- Over-range indication: The highest digit of (1) or (-1) is displayed
- Low battery indication: “BT” appears on display in the last 20% of battery life
- Battery life: up to 200 hours with Alkaline battery
- Power requirements: single 9V battery
- Operating temperature and humidity: 0˚ to 40˚C (32˚ to 104˚F) below 80% RH
- Storage temperature and humidity: -10˚ to 60˚C (14˚ to 140˚F) below 80% RH
- Dimension: 8.2” (l) x 2.6” (w) x 1.3” (h)(208 x 65 x 31mm)
- Weight : 10.9 oz (308 g) including battery
ELECTRICAL SPECIFICATIONS
- Accuracies are ± (% reading + number of digits) at 23˚C ± 5˚C below 80% RH
General Measurement
AC Current
| Range | Resolution | Accuracy (50Hz/60-Hz) | Overload |
|---|---|---|---|
| 20A | 10mA |
± (2% rdg +5 dgts)
|
Protection 1000A (within 30 sec.)
200A| 100mA
600A| 1A
DC Voltage
Range| Resolution| Accuracy| Input Impedance|
Overload Protection
---|---|---|---|---
600V| 1V| ± (0.8% rdg + 2 dgts)| 10MΩ| 600V
AC Voltage
Range| Resolution| Accuracy (40Hz~400Hz)| Input
Impedance| Overload Protection
---|---|---|---|---
200V| 100mV| ± (1.2% rdg + 3 dgts)| 10MΩ| 600V
600V| 1V
Resistance (Ω)
Range| Resolution| Accuracy| Max. Open Circuit
Voltage| Overload Protection
---|---|---|---|---
200Ω| 100mΩ| ± (1% rdg + 2 dgts)| 3.5V| 600V
20KΩ| 10Ω| 0.3V
Frequency (Hz) (10Hz ~ 2KHz)
Range| Resolution| Accuracy| Max. Input Sensitivity|
Max. Allowable Applied Voltage
---|---|---|---|---
2KHz| 1Hz| ± (1% rdg + 2 dgts)| 100mVrms| 600V
Continuity Check ( )
Range| Description| Max. Open Circuit Voltage|
Overload Protection
---|---|---|---
| The built-in buzzer sounds if conductance is less than 100| 3.5V| 600V
Diode ( )
Range| Resolution| Max. Open Circuit Voltage|
Overload Protection
---|---|---|---
| 1mV| 3.5V| 600V
Peak Hold Measurement
(Capture and retain momentary voltage or current surge and display it.) AC
Current
Range| Resolution| Accuracy (50Hz~60Hz)| Overload
Protection
---|---|---|---
20A| 10mA|
±(2%rdg+10dgts)
|
1000A (within 30 sec.)
200A| 100mA
600A| 1A
AC Voltage
Range| Resolution| Accuracy (50Hz~60Hz)| Input
Impedance| Overload Protection
---|---|---|---|---
200V| 100mV| ±(1.5%rdg+8dgts)| 10MΩ| 600V
600V| 1V
Peak Detect Acquisitions Time: Approx. 100ms.
(Acquisition time is the minimum duration of a surge for rated accuracy.
Accuracy improves for longer peak duration).
SAFETY RULES
- Never ground yourself when taking electrical measurements. Keep your body isolated from the ground by using dry clothing, rubber shoes, rubber mats or any suitable and approved insulating material.
- Disconnect the input signal before touching the battery.
- When the battery power is low, replace it with a new battery to avoid possible fluid leakage.
- When the meter will not be in use for a long time, please remove the batteries from the meter to prevent the possibility of battery fluid leakage damage.