695.3(A)(1)

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charlie b

charlie b

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Please look at the attached one-line. It is a new construction project late in the design phase. The medium voltage switchgear (MSG1, MSG2) will be outdoors and is the building owner's property. The utility insists on having full access to the gear, and their people would perform the "return to normal" operation subsequent to a loss and then restoration of normal power. The transformer is outdoors, and the switchboard SWB1 is indoors.

Would the point of connection of the fire pump tap be in compliance with 695.3(A)(1), specifically the "tap ahead of the main" and the "not in the same cabinet, enclosure, or vertical switchboard section as the service disconnecting means"?

View attachment One-Line Diagram.pdf
 
Would the statement ahead of the service disconnecting means NEC 2008, be either of the double ended feeder switches.It appears the FWP is downstream.

dick
 
That question was asked by someone reviewing the design. Here are two viewpoints:
  1. The point of demarcation between the owner and the utility is at the 34.5kV switchgear outside the building. Therefore, for the fire pump tap to be ?ahead of the service,? it would have to be upstream of the switchgear. That would mean the design shown on the attached PDF would not be in compliance.
  2. Regardless of where the utility ends and the owner?s property begins, this particular building has a service disconnecting means within the switchboard SWB1. Therefore, the fire pump tap can be at the location shown on the attached PDF.
Which viewpoint correctly represents the code requirement?
 
A confusion factor going on,,,,the Service Disconnect located in the FWP Controller is being fed by SWB2,whats going on there and is that disconnect a center position off?

I guess it would have to be or the source voltage at SWB2 maybe an alternate service,in that case then the Oneline would be correct I believe but needs to convey a bit more info or reference to SWB2 Oneline..........

Good question,,,,,,,where's the document checkers:D

dick
 
There is an automatic transfer switch that allows the fire pump to get its power from either SWB1 or SWB2. When I created the PDF from the CAD file, I took out a lot of cluttering detail, and that included the ATS description. Sorry for the confusion.
 
Then I say #2 above. with one small reservation ,I think all of 695 is in the picture in most part.

dick
 
I issued the drawing as shown on the sketch in post #1. So I considered to be compliant. One of the prospective contractors asked the question. I was curious as to whether anyone thought the AHJ, or in particular the Fire Marshall, might have an issue with this configuration.
 
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