Safety Tester
Impulse/Surge Tester

7703  is a 2-channel 5KV  impulse winding tester and able to measure inductance down to 0.5uH as well as magnify high-frequency harmonics to prevent shorts between the layers of windings. Mild corona occurring between coils would create harmonics with small amplitude and high frequency (>10MHz) which cannot be detected by a regular impulse winding tester that can only observe mild amplitude without actually identifying the fault. MICROTEST 7703 deploys “High-frequency harmonics analysis HARM “technique to magnify high-frequency harmonics then display them on screen then identify each mild discharge between layers and ensure the quality of each component coil.

  • High-frequency harmonics analysis has the capability to detect slot lines
  • Low power non-destructive test analysis
  • Automatic Level Control Function (ALC) 
  • Waveform learning comparison to achieve rapid test speed
  • Measure voltage up to 5,000V
  • Measure the lowest inductance to 0.5uH
  • Interchangeable between Chinese and English operational interfaces/ Provide statistic and print functions
  • High-frequency noise signal analysis has the capability to detect slot line
  • Auto voltage Learn function

Measurement Data

Channel 2
Impluse Voltage 200V ~ 5000V
Lowest Inductance Value 0.5uH 


Measurement Time  50mS
Measurement Mode

The comparison between standard and test waveforms


Pass/Fail HV LED red-green indicator lights/Screen Display/Sound


Power Supply 98 ~ 132Vac or 192 ~ 264Vac
Display 320*240 dot-matrix display
Interface RS-232, Print Port, Remote Control
Flash Memory

Storage of 200 rewritable data sets

Operation Auto、Manual
Environment Temperature : 10 to 40    Humidity : 20 ~ 90%
Dimension (W*H*D) 435x133x525  (mm)
Weight   8 (Kg)

Measurement Items


Total Area

Area size comparison

Waveform comparison




Quantize high-frequency harmonic waves for the datamation of short circuit problems

MICROTEST 7703 provides “High frequency noise signal analysis HFLT”funtion to quantize the data of all the high-frequency harmonics into numeric numbers that interpret harmonic wave changes. This model will setup upper and lower thresholds according to these figures and has the capability to detect even the smallest short between layers.


Utilize high-frequency harmonics analysis function, detect the most typical problems of high voltage slot line

After the test, we found out the parameters e.g. Area under the curve, Area size and waveform comparison are all PASS, but high-frequency harmonics and high-frequency noise signals are out of specification, this short-circuit problem between layers is caused by high voltage slot line.


Inverters, Power Inductors, Winding, Transformers, Motors, Wave Filters, Capacitors and Circuit breaker

No relevant audio and video files

Standard Accessories

  • Power Cord
  • User Manual
  • HV Test Cable
  • D-Sub footswitch

Optional Accessories

  • Impulse Link Software
  • RS-232cable
  • Remote Cable