arrester disconnect switch

ECI manufactures an externally operated switch that provides a means of performing electrical testing of transformers that are equipped with an internal under-oil lighting arrester.

When performing the ANSI required impulse test on a transformer, the under-oil arrester must be removed from the circuit or else the arrester will operate, and the transformer coils will not be tested. the arrester disconnect switch must be open before dielectric testing of the transformer to prevent misleading results and possible arrester damage.


To open the switch, unscrew the pipe plug, pull the plug out to the stop to disconnect the arrester ground. Reverse the procedure to close the switch.

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