Motor Rotor Testing System
MT-6920 (24/48 Channel)

Motor Rotor Testing System|MT-6920 (24/48 Channel)
  • 24/48 Channels
  • Hipot/Leakage Current
  • Insulation Resistance
  • Winding Layer short Test
  • Resistance Welding Test
  • Inductance Test
  • It can test multiple sets of DUTs simultaneously
  • 4-Wire DC Resistance measurement will be more accurate than others
  • The Impulse/Surge with waveform comparison is a non-destructive analysis
  • Chinese/English screen could be switched arbitrarily

MICROTEST MT-6920 motor rotor testing system provides 24 or 48 channels for testing. It allows for the measurement of welding resistance in motor rotors and integrates safety withstand voltage insulation and inter-coil short circuit testing in a single system. It supports PC connectivity software for remote programming and storage of test data. The system can be PLC-controlled and can accommodate customized testing fixtures for customer-provided rotors.




Model MT-6920
Test Channel 24/48
DC Resistance Test
DCR Range 0.1mΩ-100kΩ
Measuring Mode 4-Wire
DCR Accuracy

Low Resistance


High Resistance


Safety Hi pot Test
AC Output Voltage 100V-3000V
AC Leakage Current 0.001mA-10mA
AC Arcing Detection Detect gears from 0-9
DC Output Voltage 100V-3000V
DC Leakage Current 0.001mA-5mA
DC Arcing Detection Detect gears from 0-9
IR Output Voltage 100V-1000V
Insulation Resistance 1-9999MΩ
Measuring Time 0.1-99.9s Continuously adjustable
Voltage Accuracy ±(3% of setting+5V)
Impulse Winding Test
Impulse Voltage (programmable) 200V-3000V
Impulse Voltage Accuracy ±2%
Total area comparison

When layer short happened, the loss of power on coil increase, the resonance damping coefficient increase, resonance amplitude decrease, the total area decrease. These are the basic parameters we check layer short.

By calculating and comparing the deference of area between golden sample and DUT.
Show by percentage
Analysis the power loss by this data.

Differential area comparison

Add up the difference between normal wave and DUT wave call “ Area differential”.
When layer short happened, the inductance reduce(similar the transformer). The wave phase change and the area differential also change. This will show “fail” on the instrument.
However, the parameter might cause deviation because of the deviation of inductance, resonance phase shift. (Silicon steel product such as motor and traditional transformer is not suitable)

By calculating and comparing the deference of area between golden sample and DUT. To determine the degree of waveform overlap.
Compare the inductance by this.

Wave comparison Set a acceptable wave range, if the DUT’s wave is in this range shows “pass” otherwise, “fail”
This parameter can judge both amplitude and phase of resonance wave. This can increase the detection capability of layer short.
Corona comparison In pulse test, the insulation defect will cause discharge and create corona. This function is able to count the times that corona happened base on the degree of deviation.
Detect the discharge phenomenon on the coil.
Flat comparison If the layer short happened, the waveform will tremble. Therefore, the instrument will quantize and compared it.
Inductance Measurement (Option LCR Meter 6365)
Inductance Ranges 0.1nH - 99.999KH
Test Frequency 10Hz-200kHz
Frequency Output Accuracy ±0.01%
Frequency Resolution 5 Digits
AC Drive Level 10mV to 2Vrms (1m Vrms resolution)
Basic Accuracy ±0.1%
Three-phase Inductance Balance Test

Comparison Mode

  • The absolute value of the difference between the two sets of coil inductance


  • The ratio of the absolute value of the difference between the two sets of coil inductance to the standard value


  • The ratio of the absolute value of the difference between the inductance of the two sets
    of coils and the average value of the measured resistance of the three sets of coils



Test fixture According to the test requirements
Indicator Pass/Fail Screen Diaplay/Sound
Built-in Storage Storage of 100 rewritable data sets
Operation Manual, RS-232
Power Supply Voltage 90-132Vac or 198-264Vac
Frequency 50/60Hz
Power consumption 300VA
Environment Temperature 10℃-40℃
Humidity 20-90%RH
Display 6920 5.7" dot-matrix display (320*240)
7605 4.3" TFT LCD (480*272)



6920 435x190x522mm
7605 435x145x522mm
6908 435x145x522mm
Weight 6920 15 Kg
7605 14 Kg
6908 7 Kg
Interface RS-232