Optional standby generator

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scottau

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In Florida we are installing a lot of generators for residences with automatic transfer switches. Is it ok, per the NEC(article 720), to install a 30 kva 120/240-volt generator with a 200 amp automatic transfer switch to feed a 200 amp 120/240-volt panel? :?:
 
Sure it is. Just make sure your genset has an output breaker sized for it's running current. Also be sure the homeowner knows that they don't have a 200 amp generator.
 
Well thats what I thought, but the AHJ is saying that I cannot have more load than the rating of the generator and therefore would need to provide a subpanel for the generated load or provide a manual transfer switch.
 
Bryan, thanks for the response, I agree with you and feel that if the system was overloaded than the generator would no longer provide power to the system, i.e. tripped breaker or generator malfunction, so there is no way for the system to go into a "overloaded meltdown" situation as the generator has no more power to give unlike the power company. Therefore I don't see a safety issue, which the NEC would be trying to prevent. Also the likelyhood of all the possible loads being utilized at the time of transfer and during generator use is highly unlikely. This same reasoning is why we can derate the service cables per NEC 310.15 (b). Furthermore the reality is even with everything in the average house turned on the load is considerably less than the rating of the main panel.
 
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