transfer switch installation for generator

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jerid

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south charelston ohio usa
My local inspector is requiring a fourth wire to be added from the se rated transfer switch on an existing 200 amp underground service on the basis that the automatic transfer switch is the first means of disconnect. I want to install transfer switch and generator after meter, before house panel main breaker.Meter is on pole 175 feet from house. NO room at house to install transfer switch or generator! Is this a correct ruling? If so, any way to solve this problem? Thanks Jerid
 
If the transfer switch is a main disconnect then 4 wires are required. Remember the pole is a remote structure and as such art. 250.32(B) would require a 4th wire depending on which code cycle you are on.
 
ats for gen

ats for gen

Thanks for the inputs. I guess I just can't get in the right groove on this.... On an ATS, there is no manual way to put the ATS in OFF position.The ATS switches from ON [normal power] to ON [generator] when power is cut. You would also have to shut down the circut breaker on the generator for a complete power shutdown . So,to my way of warped thinking it wouldn't be a DISCONECT persay! JERID
 
jerid said:
Thanks for the inputs. I guess I just can't get in the right groove on this.... On an ATS, there is no manual way to put the ATS in OFF position.The ATS switches from ON [normal power] to ON [generator] when power is cut. You would also have to shut down the circut breaker on the generator for a complete power shutdown . So,to my way of warped thinking it wouldn't be a DISCONECT persay! JERID
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Then the transfer switch you have is not service rated, if you use it, you will have to put a disconnect before it.
 
jerid said:
Thanks for the inputs. I guess I just can't get in the right groove on this.... On an ATS, there is no manual way to put the ATS in OFF position.The ATS switches from ON [normal power] to ON [generator] when power is cut. You would also have to shut down the circut breaker on the generator for a complete power shutdown . So,to my way of warped thinking it wouldn't be a DISCONECT persay! JERID
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If you truly have an SE rated switch it will have a disconnect for the utility supply. That does not mean it will have a disconnect for the generator source as that is covered by other means. The inspector is correct, you need 4 wire from the ATS to the house. At the house you need to remove the neutral bond, but you still need an grounding electrode system at the house.
 
texie said:
If you truly have an SE rated switch it will have a disconnect for the utility supply. That does not mean it will have a disconnect for the generator source as that is covered by other means. The inspector is correct, you need 4 wire from the ATS to the house. At the house you need to remove the neutral bond, but you still need an grounding electrode system at the house.
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The UL. General directory says a service rated transfer switch will have an externally operable disconnect for both sources.
 
iwire said:
The UL. General directory says a service rated transfer switch will have an externally operable disconnect for both sources.
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I'm not sure that is always the case. If both sources are a utility, then yes. If it is 1 utility source and 1 generator I think the internal disconnect is not required on the generator input side. In fact, I have installed them supplied this way.
 
texie said:
I'm not sure that is always the case. If both sources are a utility, then yes. If it is 1 utility source and 1 generator I think the internal disconnect is not required on the generator input side. In fact, I have installed them supplied this way.
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You are right, it may have changed or I remembered it wrong.

From the 2010 General directory



Automatic transfer switches are required to be designed so that the load
cannot remain simultaneously disconnected from both the normal and
alternative sources when either or both sources are available, except that
transfer switches marked ??SUITABLE FOR USE AS SERVICE EQUIPMENT??
are provided with externally accessible means to independently
disconnect each source intended to be a service.
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iwire said:
You are right, it may have changed or I remembered it wrong.

From the 2010 General directory
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I don't think you remember wrong, rather a misunderstanding of the wording as it is a little fuzzy. I think the last few words "each source intended to be a service" gives the out for the generator to have a disconnect built in. In those cases where the second source is another utility source, I agree that you would need them on both sources. It's a little more rare of an application, but it happens.
 
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