Cold Sequence Disconnect

[shortcircuit2]

In the NEC the meter disconnect allowed on the supply side of the service disconnect by 230.82(B) for cold sequence metering required by many utility companys on 480 volt services must be able to withstand the available fault current under 230.82(B)(1).

All the non-fusible disconnects are rated at 10,000 short-circuit amps max. So if the available fault current is over 10K then you have to you a fusible switch, correct?

Just looking for some feedback from those who have done such an installation...

shortcircuit2

 

[augie47]

That's the way I look at it, however, when it was brought to POCOs attention locally they and the State opted to consider it as a part of their distribution system and removed it from NEC inspection

 

[tom baker]

Yes on the AIC. We have been installing disconnects ahead of the meter since 1982, code didn't recognize until 2005.

Where it gets dicey is who do those fuses belong to? POCO may want there lock on disconnect...
Our AHJs allow it as its required by the POCO, much as a meter is, but neither are required by NEC.