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Thanks for the continuing NEC information.
If I install a generator on a dwelling and use an automatic transfer switch, is the maximum time for transfer 10 seconds? I have an inspector requiring this. I thought this was for emergency systems.
Any help would be appreciated.
Not to get between you and the inspector, but in this instance, we believe your thinking is correct. A generator installed at a dwelling is an optional standby system and the provisions of Article 702 apply. Section 702. 4 indicates that manual or automatic transfer equipment can be used. There does not appear to be a 10-second time limit for automatic transfer of the normal to standby power as there is in 700.12 which addresses emergency systems.
Hope this helps clarify.
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