2ms, 150A-2200A Energy screening test for arrestor MOV test

Download: HICG Impulse Current Generator.pdf

This equipment is for removing the defective ZnO elements ocuurred during fabrication processes by applying 2ms-long duration impulse current wave test according to IEC60099-4.

Production type : Metal Oxide Varistor(MOV)

Test interval：The test interval can be specified between 1 to 5 minutes. The usual test interval is 1 minute.

Charging time：

The three test terminals are discharged sequentially, and the elements are moved in order through each test terminal using a turntable. Under the test condition of three applications per minute, the charging time for each discharge must be within 10 seconds.

Equipment rating :

The rating of the impulse current test equipment may adhere to any manufacturer-recommended conditions, provided it satisfies the test requirements, with reference circuit conditions provided below.

Charging transformer : 50kV/40kVA

Max charging voltage : 50kV (DC), Max charging current 1A

Charging time : within 10 seconds at full of condenser 

Inductors : xx sets from 0.5mH to 2.5mH, or 10sets 8mH

With multi-tap to change inductance.

Impedance matching resistors : 1 ~ 10Ω

Waveform time : 2~2.4ms (0%+20%), 150A-2200A

L and C will be in appropriate values.

IEC60099-4: Edition 2.2 2009-05 “8.4.2 Line discharge test requirements”

The test may be carried out with any generator fulfilling the following requirements.

a) The virtual duration of the peak of the current impulse shall be between 100% and 120% of the value specified in Table 1.

b) The virtual total duration of the current impulse shall not exceed 150% of the virtual duration of the peak.

c) Oscillations or initial overshoot shall not exceed 10% of the peak of the current value. If oscillations occur, a mean curve shall be drawn for the determination of the peak value.

The impulse current generator shall be disconnected from the test sample later than once and earlier than twice the virtual total duration of the current impulses after passing through zero.

Measuring instrument

Current Transformer : 5000A

 Primary current : 100~5000A, Through type

Secondary current : 5A

Rated burden : 15VA

Voltge divider : 25kV/250V

Test interval : 10 seconds and can be set to 99 seconds

Rated pulse repetition : 6 pulse per 60s

The test interval can be adjusting by the operation software interface

Cooling system for elements after testing

After withstand testing, the elements become hot, posing a risk of burns during manual extraction. A cooling period is established for the elements from the end of the test until their discharge, during which they are air-cooled using fans. Temperatures of the elements at the discharge area are measured using non-contact thermometer. The measured temperatures are displayed, and if they exceed 50°C (adjustable), a warning such as 'Element High Temperature Alert' is shown. The cooling air should be directed so as not to hit the elements during the test.