High current test combined with hipot test on LV and HV cable accessories

Sefelec manufactures current injection sources in combination with hipot testers in order to answer to some international standard for the high current tests on cable accessories, underground connection accessories, low voltage underground network connection, high voltage cable accessories (outdoor terminations, switchgear terminations, transformer terminations, …), …

The concerned accessories are for instance connected to the following standards: NF (C 33-002), NF (C 33-210), ... The following European document of harmonization also gives details of the method to follow: CENELEC HD605S1.


Definition:
The long run tests (also called ageing test) are made during several hours, days or months.
The accessories under test are often put under ground, under water, or in the air for the test, and are submitted to thermic cycles by applying an AC current.
An AC voltage is also permanently applied at the same time between phase and ground ; this test is called the hipot test (also called hi-pot test, dielectric withstand test, dielectric strength test, breakdown test, or flash test).
No breakdown (also called flash, arc) should occure during this test.


Example of typical Test:
This ageing test (also called run test) made on the accessories combines a test in current (thanks to a window transformer, also called current injection transformer) at for instance the following AC voltage/current : 20/24/36 VAC, 3 x 700A or 10VAC, 1 x 1200A, …), and a test of hipot (at for instance 2kVAC, 50 mA, 60 kVAC, 200kVAC, …).
A loop is made with the cable.
This loop holds 2 or 4 accessories.


Test specifications:
An example of the duration of the ageing test could be the following one :
210 cycles of 24 hours (8 hours heat up / 16h cooling cooling down) at (100 ± 5) °C
= 5000 hours under voltage
= 7 months

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