separate service

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hhsting

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Attached sketch. I have two incoming service conductors. One conductor 4#600kcmil underground goes to fire pump room into fire pump controller factory install breaker and has grounding electrode system and other 4#600kcmil underground to electrical room main service switchboard. The electrical room and fire pump room are right next to each other.

NEC 2014 section 230.2 first paragraph exception no.2 if more than 1/0 AWG or larger from same source and at same location but different load would be one service. I am confuse about attached sketch. Would this count as separate service or one service?
 

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augie47

augie47

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Shame we ran out of toilet paper but you still have sketch paper :) Since the 2nd supply is for a fire pump it is likely considered a separate service asd allowed by 230.2(A)(1). Either way it needs to be treated as any service and be connected to the building grounding electrode system, etc.
 
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hhsting

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augie47 said:
Shame we ran out of toilet paper but you still have sketch paper :) Since the 2nd supply is for a fire pump it is likely considered a separate service asd allowed by 230.2(A)(1). Either way it needs to be treated as any service and be connected to the building grounding electrode system, etc.
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:) But this is a new construction everything. So I am trying to figure out if this is considered separate service or not by code? It’s the other way around I want separate service. Fire pump needs to be fed from separate service
 
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hhsting

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hhsting said:
:) But this is a new construction everything. So I am trying to figure out if this is considered separate service or not by code? It’s the other way around I want separate service. Fire pump needs to be fed from separate service
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I apologize for my ignorance but I am really stuck on this one. I searched on my own in code but not able to find definite sections. Sorry for my ignorance. I guess this might probably end like other thread no one willing to help or answer further. Where is my buddy Electrofelon?
 
electrofelon

electrofelon

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I agree with Augie, separate service. I believe the intent of the code is that a fire pump is always a separate service (even though I think they blundered the wording and structure a little and it could be considered same service but two sets under 230.40 exception 2 but would have to be grouped, but I think thats not the intent).
 
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hhsting

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electrofelon said:
I agree with Augie, separate service. I believe the intent of the code is that a fire pump is always a separate service (even though I think they blundered the wording and structure a little and it could be considered same service but two sets under 230.40 exception 2 but would have to be grouped, but I think thats not the intent).
Click to expand...

Would you say that fire pump is supplied by a connection located ahead of Main Switchboard MSB service disconnecting means in post #1 attachment top part?
 
infinity

infinity

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It's fed ahead of the main switchboard. Couldn't this just be one of the permitted six (or seven) service disconnects?
 
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hhsting

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electrofelon said:
Seems to me if it were installed under 230.40 ex #2 it would have to be grouped. 230.72(B) does not seem to apply to 230.40 Ex #2. Thus if it is not grouped, I see the only option is that the fire pump is a separate service.
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But the fire pump service disco is allowed to be not grouped. So it confuses the matter separate service or fed ahead of main service switchboard?
 
electrofelon

electrofelon

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electrofelon said:
Seems to me if it were installed under 230.40 ex #2 it would have to be grouped. 230.72(B) does not seem to apply to 230.40 Ex #2. Thus if it is not grouped, I see the only option is that the fire pump is a separate service.
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Ok, I am going to amend my stance based on 695.3(A)(1) and 230.82(5). I have never liked 230.82 since, as with PV, it brings in this nebulous thing about normal/not normal disconnects. Everything should just be covered under 230.40 exceptions with modifications to the grouping requirements if needed.

Anyway, I am leaning toward it being a separate service in your situation.
 
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hhsting

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electrofelon said:
Ok, I am going to amend my stance based on 695.3(A)(1) and 230.82(5). I have never liked 230.82 since, as with PV, it brings in this nebulous thing about normal/not normal disconnects. Everything should just be covered under 230.40 exceptions with modifications to the grouping requirements if needed.

Anyway, I am leaning toward it being a separate service in your situation.
Click to expand...

You see their is a local amendment where they changed 695 to say at this AHJ says: The following amendments, and/or additions are made to Article 695 of the National Electrical Code: (1)A fire pump shall be supplied by a separate service from the utility transformer.(2) A fire pump shall be permitted to be supplied from a connection located ahead of the service disconnecting means when a back-up on-site generator is used as an alternate power source to feed the fire pump.

I am just trying to figure out if post #1 falls under #2 above if I need back up onsite generator if connected ahead of service disconnecting means or #1 above.

NEC 2014 section 695.3(A)(1) a tap ahead of the service disco mean shall comply with 230.82(5). 230.82(5) says supply side of service disconnect.

So first I am not sure if the attach sketch post #1 would need generator or not per local amendment if connected ahead of service disconnect or is it connected ahead of service disconnect or not, falls under #1 or #2 local amendment above ? Second what is supply side of service disconnect no definition is provided?
 
augie47

augie47

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Since you have local amendments, it's best to run it by your local AHJ. By definition they are the authority, not us.
Post 2,5,6,12,&13 all give you the opinion that it's a separate service in which case your local ammendment #1 would apply but, again, that's YOUR AHJ's call.
"Supply side of the service disconnect" is exactly what the words say. Supply side ie: ahead of the service disconnect
Your original post asks if we thought it was a separate service .. answered numerous times.. YES
 
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