Question two outside feeders

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hhsting

Senior Member
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Glen bunie, md, us
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I have drawings where main service switchboard is being replaced in kind. While switchboard is replacing there are two outside temporary generator powering distribution panels downstream. See below snapshot.

The two temporary generators are outside and feeders are coming into building. Question are multiple outside feeders allowed to be fed to the
building from the two temp generators or not? I looked at NEC 2017 Article 225.30 and found only one outside feeder is allowed but in this situation not sure
b08354cd5c72a764b009d3f748fe0e21.jpg
 
infinity said:
For a temporary installation I would argue that 225.30(E) can be applied if properly implemented.
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My question is NEC 2017 Article 225.30 first paragraph says feeder on the load side of service disconnecting means shall be supplied by one feeder.

Definition of service NEC 2017 Article 100 says conductors from serving utility. Applying that definition Where is the service disconnecting means for stand alone generator?
 
hhsting said:
My question is NEC 2017 Article 225.30 first paragraph says feeder on the load side of service disconnecting means shall be supplied by one feeder.
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You're not reading the entire section. It states "shall be supplied by only one feeder or branch circuit unless permitted in 225.30(A) through (E)". If they can comply with (E) then more than one feeder is permitted.
 
infinity said:
You're not reading the entire section. It states "shall be supplied by only one feeder or branch circuit unless permitted in 225.30(A) through (E)". If they can comply with (E) then more than one feeder is permitted.
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But the whole section 225.30 including your 225.30(A) through (E) applies to feeder load side of service disconnecting means.


I domt have service disconnecting means. These would be standalone customer owned generators.
 
hhsting said:
But the whole section 225.30 including your 225.30(A) through (E) applies to feeder load side of service disconnecting means.
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That is a good point, 2017 NEC 225.30 does not apply to feeders not supplied from a service. So there's no problem with the configuration shown in the OP.

Cheers, Wayne
 
infinity said:
So is there any code section that actually applies to this installation?
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Article 710 would apply, but there are no rules that directly apply to the question. 590 would also apply, but again there is no specific rule that directly applies.

Also nothing in Part II of Article 225 would apply because there is no service and Part II only applies to "a building or other structure that is served by a branch circuit or feeder on the load side of a service disconnecting means" and there is no service disconnecting means

I see no reason to be concerned or to reject the installation.
 
don_resqcapt19 said:
Article 710 would apply, but there are no rules that directly apply to the question. 590 would also apply, but again there is no specific rule that directly applies.

Also nothing in Part II of Article 225 would apply because there is no service and Part II only applies to "a building or other structure that is served by a branch circuit or feeder on the load side of a service disconnecting means" and there is no service disconnecting means

I see no reason to be concerned or to reject the installation.
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Looking at it again since 225.30 specifies after the service disconnect there in nothing in the NEC that directly governs the installation (two generators) in the drawing presented in the OP.
 
infinity said:
Looking at it again since 225.30 specifies after the service disconnect there in nothing in the NEC that directly governs the installation (two generators) in the drawing presented in the OP.
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Exactly, but as I said, I see no reason for concern, and since there is no specific rule, there is no reason to reject the installation.
 
don_resqcapt19 said:
Also nothing in Part II of Article 225 would apply because there is no service and Part II only applies to "a building or other structure that is served by a branch circuit or feeder on the load side of a service disconnecting means" and there is no service disconnecting means
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2023 NEC Article 225 Part II does not say that. The title of Part II does not have the limiting phrase "on the load side of a service disconnecting means."

225.30 does include that limiting phrase, so 225.30 does not apply to the install in the OP. But 225.31(A) certainly still applies: "Means shall be provided for disconnecting all ungrounded conductors that supply or pass through the building or structure." Etc.

Cheers, Wayne
 
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wwhitney said:
2023 NEC Article 225 Part II does not say that. The title of Part II does not have the limiting phrase "on the load side of a service disconnecting means."

225.30 does include that limiting phrase, so 225.30 does not apply to the install in the OP. But 225.31(A) certainly still applies: "Means shall be provided for disconnecting all ungrounded conductors that supply or pass through the building or structure." Etc.

Cheers, Wayne
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I guess you missed my part about application of NEC 2017 Article 250.32? That should apply no?


Sent from my iPhone using Tapatalk
 
wwhitney said:
2023 NEC Article 225 Part II does not say that. The title of Part II does not have the limiting phrase "on the load side of a service disconnecting means."

225.30 does include that limiting phrase, so 225.30 does not apply to the install in the OP. But 225.31(A) certainly still applies: "Means shall be provided for disconnecting all ungrounded conductors that supply or pass through the building or structure." Etc.

Cheers, Wayne
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You are correct, but once you are past 225.30, there is no issue with having two feeders.
The location of the disconnects is not clear on the one line, but even if they are remote from the building, Exception 1 likely applies.
 
don_resqcapt19 said:
You are correct, but once you are past 225.30, there is no issue with having two feeders.
The location of the disconnects is not clear on the one line, but even if they are remote from the building, Exception 1 likely applies.
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They are remote from each other. One is in electrical room inside and another outside wall opposite to electric room
 
hhsting said:
They are remote from each other. One is in electrical room inside and another outside wall opposite to electric room
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Assuming the generators are next to each other, I would put the generator OCPDs at the generators and apply Exception 1 to 225.31.
 
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