790602 Varistor tests for clamping voltage - Generator


Varistors are clamping devices used to protect power systems from voltage surges generated either by lightning discharge or switching in power circuits. Varistor tests for clamping voltage and energy absorption require use of the 8/20 µs, 10/350 µs and 10/1000 µs current impulses. Often referred to as SPDs or MOVs, varistors are required to have power dissipation tested in event that the device is activated. Under these conditions there is a high follow current from the power supply conducted through the varistor.

Application Standards

  1. IEC 62475
  2. IEC 61000-4-5
  3. ITU-T K44
  4. ITU-T K77
  5. ITU-T K96
  6. IEC 62368-1
  7. IEC 61051-2
  8. IEC 60099-4
  9. IEC 61643-31

Test types

  • 10/350µs or 10/1000µs Current Impulse Testing of Transient Rating (WTM)
  • 8/20µs Current Impulse to test Peak Current Handling (ITM)
  • 8/20µs Current Impulse to test Clamping Voltage (VC)
  • Combination Wave Impulse (CWG) to test network connected SPDs


Product Page

110980%20-%20CTS101000 Varistor tests for clamping voltage - Generator
1 kA impulse current generator 10/1000us
Dual output generator for testing 2 and 3 terminal Surge Protection Devices (SPD). An integrated safety circuit linked with a large volume test cabinet ensure personnel safety.
103663%20MIG0603CLV1 Varistor tests for clamping voltage - Generator
Varistor clamping voltage tester
Multiple meausrement ranges ensure a highly accurate varistor clamping assessment up to 200A. For use with SMD or radial varistors.
103528_MIG2412SPD_whitebg Varistor tests for clamping voltage - Generator
Compact impulse generator for SPD testing
MIG2412SPD can be used for efficient testing of clamping, crowbar and combined surge protection devices to meet IEC 61643-11 class I, II and III requirements

More Options & Comfort

Impulse generators cover the range 20 A for testing SPD devices up to 100 kA for testing high voltage varistors. Testing directly with AC power is possible with Coupling Decoupling Networks up to 1,200 Vac. All high voltage outputs can be covered with TC-ST test cabinet for personnel safety. 


Baselstrasse 160
CH - 4242 Laufen

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