Fire Pump Service

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jeff1166

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I have a project that requires a 125 HP Fire pump. The local power company is telling me they they have to set a seperate transformer for the pump. So the building will have two transformers...one for the building service and one for the FP. The owner is not happy about buying two transformers and I have done other buildings similar to this one with one transformer. Can anyone tell me where to look in the NEC regarding a seperate transformer.

Thanks for your help
 
But just in case it isn't clear, two separate services can be fed from the same transformer.

I guess we are pretty lucky where I am. The POCO always provides the transformers. (Although, they are also providing us with a 50% rate hike over the next 3 years :mad: )
 
I understand that the FP needs to have a seperate service but I am not clear about being on a seperate transformer. The owner is having a hissy about buying two transformer and he would like me to provide documentation stating two transformers are not necessary. This is the first time I have been asked to provide two transformers. Are you saying one tranformer can feed both the FP and the building service? If so where are you reading that?

Thanks so much for your replies
 
jeff1166 said:
I understand that the FP needs to have a seperate service but I am not clear about being on a seperate transformer. The owner is having a hissy about buying two transformer and he would like me to provide documentation stating two transformers are not necessary. This is the first time I have been asked to provide two transformers. Are you saying one tranformer can feed both the FP and the building service? If so where are you reading that?

Thanks so much for your replies
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There is not enough info from the op regarding transformer size pole or pad mount and total kVA load from the building in question. There is a possability that the pocois concerned with supplying normal power and the pump from a single transformer have you inquired as to why the poco is not considering a single larger xformer???
 
There is not enough info from the op regarding transformer size pole or pad mount and total kVA load from the building in question. There is a possability that the pocois concerned with supplying normal power and the pump from a single transformer have you inquired as to why the poco is not considering a single larger xformer???
__________________
Charlie
"He that hath a Trade, hath an Estate. " B Franklin





Charlie,
I asked the power company and their response was it is a code violation to service the FB and the building service from one transformer. When I pressed the issue of the code reference the response was...he was not sure of the code but that is how they do things. So I am not sure it is a NEC vioation but maybe their own codes.
 
Where reliable, Section 695.3(A)(1) permits a fire pump to be supplied by a connection located ahead of the service disconnecting means. This is often from the secondary compartment of a utility transformer. In such cases a single transformer is used.
 
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RB1 said:
Where reliable, Section 695.3(A)(1) permits a fire pump to be supplied by a connection located ahead of the service disconnecting means. This is often from the secondary compartment of a utility transformer. In such cases a single transformer is used.
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I don't belive that is completely correct, but one could make that arguement.

(A) Individual Sources Where reliable, and where capable of carrying indefinitely the sum of the locked-rotor current of the fire pump motor(s) and the pressure maintenance pump motor(s) and the full-load current of the associated fire pump accessory equipment when connected to this power supply, the power source for an electric motor-driven fire pump shall be one or more of the following.
(1) Electric Utility Service Connection A fire pump shall be permitted to be supplied by a separate service, or from a connection located ahead of and not within the same cabinet, enclosure, or vertical switchboard section as the service disconnecting means. The connection shall be located and arranged so as to minimize the possibility of damage by fire from within the premises and from exposing hazards. A tap ahead of the service disconnecting means shall comply with 230.82(5). The service equipment shall comply with the labeling requirements in 230.2 and the location requirements in 230.72(B). [NFPA 20:9.2.2]

IMO the POCO may not have a transformer that can carry the load of the building and supply a 125hp motor.
 
jack horner said:
I don't belive that is completely correct, but one could make that arguement.


IMO the POCO may not have a transformer that can carry the load of the building and supply a 125hp motor.
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agreeded

BUT, I do not believe one transformer violates the NEC,(but I am at home now and I do not have NFPA 20 with me)
 
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