fire pump controller having pulled neutral and egc from generator having 3 poles ats to the building with same generator feeding ats & fire pump

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loco79

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miami
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electrical inspector
it is this sound right to do since 250.6

can some one reply back clarification about this diagram
i think is a code violation because ats 3 poles
since generator wiring comes from same place from inside the generator windings
 

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So long as the generator neutral isn't bonded to ground as well, there will be no objectionable current.
 
CoolWill said:
So long as the generator neutral isn't bonded to ground as well, there will be no objectionable current.
Click to expand...
So it is OK to pull neutral to the fire pump controller from generator without having objective current?
 
But inside fire pump controller both conductors will be connected together in the same spot with two mechanical lugs

So neutral and egc will be in the same spot
 
loco79 said:
So it is OK to pull neutral to the fire pump controller from generator without having objective current?
Click to expand...
No, I didn't realize they go to the same lug in the controller. No, that isn't right. Why is it like that?
 
CoolWill said:
I've never seen one. Is there no way to unbond the neutral or to add a ground out?
Click to expand...
Usually a separate service or an isolated service is required to them. The pump itself does not use a neutral, but has to be brought to all service disconnects if present. They are thousands out there like that with no issues.
 
CoolWill said:
No, I didn't realize they go to the same lug in the controller. No, that isn't right. Why is it like that?
Click to expand...
There should be no bonding of the neutral at the gen.

The normal power supplies a bond back to the gen

The fire pump controller has normal power correct?

Sent from my SM-S901U using Tapatalk
 
please any one will confirm this type of installation will not have objective current back to the generator since ats is three poles?
 
@loco79

You have to supply more information to get the answer you are looking for. What powers the fire pump? Just the generator?? Does the generator supply only the fire pump or does it also serve other loads?
 
CoolWill said:
The OP shows the bond in the main panel and a solid neutral transfer switch. And then the neutral bonded to ground again at the pump controller
Click to expand...
Anytime you have more than one service disconnect enclosure and you use the individual grounding electrode allowance from each of the service disconnects you will have a bond at the electrode that ties the neutral path together

A fire pump service disconnect location separated from the normal power service disconnect is still going to have a GEC bonded to the same grounding electrode system as the other service disconnects in the building

Mike Holt once said as an illustration think of the neutral/ bond like the

common on a 3 way switch

If it's bonded at the gen than it's not bonded at the transfer switch.

If it's bonded at the transfer switch it's not bonded at the gen
 
Eddie702 said:
@loco79

You have to supply more information to get the answer you are looking for. What powers the fire pump? Just the generator?? Does the generator supply only the fire pump or does it also serve other loads?
Click to expand...
generator and FPL utility service
 
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