NEC 230.204 Isolating Switches Question

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farmaped

Member
I have questions on the Isolating Switch requirements of services over 1,000 Volts, specifically when a vacuum circuit breaker constitutes the service disconnecting means.
2014 NEC Article 230.204 excepts an isolating switch ahead of a VCB whe the VCB "is mounted on removable panels or switchgear units where both of the following conditions apply: (1) Cannot be opened unless the circuit is disconnected (2) Where all energized parts are automatically disconnected when the CB is removed from operating position"
Does a drawout VCB meet these exceptions? if yes, how to meet 204.204(D) Connection to Ground? Would an available drawout grounding cart meet this?
Thanks
 

big john

Senior Member
Location
Portland, ME
The way it reads to me is that having a circuit breaker as your air-gap removes the need for the isolation switch or any of the design requirements for that isolation switch, i.e., a breaker alone would be sufficient.

This tends to be supported by the fact that I've seen many facilities that work exactly like that--breaker isolation only and manual grounding--and that I don't know of any mechanism that will automatically ground a circuit upon racking a breaker.
 
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