225.39(D) Where is feeder disconnect permitted?

[gene6]

We had a recent thread about this for services but now I am faced with the following:
There is a pump house has more than two circuits on a 4 wire 10/3 UF cable.
I have not done a load calc but I imagine its under 7200W.
The panel has rusted out and needs replaced.
There is a 2 pole 30 in the main house for this feeder, that is the feeder disconnect.
Now I don't want to replace this feeder.

Can I add a 60A disconnect on the main house where the LB is now and the conduit dives into the ground ? ?
Or would the 30A breaker in the service still be the feeder disconnect?
And if so can it be a 60A breaker or does it need to be a 60 amp rated fused disconnect with 30A fuses to create a new feeder?

 

[tom baker]

The UF is required to be protected at its ampacity of 30 amps, at the house.

 

[gene6]

Thanks Tom the feeder is protected at 30 Amp but 225.39(D) is telling me I need a feeder disconnecting means of 60 Amps because the pump house has more than 2 circuits. The inspector will not accept a 60A disconnect at the pump house because its not the feeder disconnect. So I am asking if I can create a 30A feeder off a 30A feeder, using a 60A disconnect fused at 30 amps?
Like so:
Feeder #1 | Feeder #2
House 30A breaker ----> 60 Amp disconnect with 30A fuse ---> pump house panel (backfed 60A as disconnect)

 

[Little Bill]

Does the panel in the shed have a main breaker? The inspector is probably wanting a disconnect at the shed. If the State is on anything before the 2020 code, then the "six throws of the hand" rule can be used. That's if the panel has six or fewer breakers.

 

[gene6]

Thanks Bill I have not replaced the panel yet and yes it will have a main breaker.
This is what the inspector says:
"240.21 requires overcurrent protection to be
located at the point where the conductors receive their supply (at the originating panel)
per 225.39 this disconnecting means shall have a rating of not less than the
calculated load to be supplied, and in no case shall the rating.
be lower than specified in 225.39(A)-(D).

225.52 deals with the location of the building or structure disconnecting means this is additional
to the feeder or branch circuit disconnecting means and the rating of this disconnect is not addressed in 225.39."

 

[jaggedben]

It sounds like the inspector is citing the very-often-overlooked requirement that feeders to separate buildings for more than one circuit be a minimum of 60A. 225.39(C). I have never seen this enforced and it is my personal opinion it should be deleted from the code. However if he insists on it you may be SOL and have to replace the UF cable. Perhaps a load calc will help (if based on more than your imagination). Perhaps if he is the legalistic type a 60A fused disconnect with 30A fuses will pass.

 

[gene6]

Tom, Bill, Ben thank you for your time and expertise it all makes sense now.
I was proposing a 60A breaker or a non fused disconnect but the inspector (a private firm here) was saying they cannot assist with designs, yet he hinted that there is a work around relating to the code definition of a feeder. That workaround is Bens suggestion, existing 30A feeder to a 60A fused disconnect with 30A fuses. No OCPD = same feeder so the disconnect must be fused and a oversized main does not create a new feeder.

very-often-overlooked requirement

In upstate NY it seems getting a permit is a very-often-overlooked requirement. Thankfully they do plan review if the total work is over 20k, with inflation is not that much anymore. Lucky for me I have not even started work yet.

 

[wwhitney]

225.39 only governs the rating of the disconnect at the building supplied, not at the source. There is zero reason that a 30A feeder from the originating building (30A conductors, 30A source OCPD) can't terminate in a 60A disconnect at the building supplied. Whether fused or unfused.

Cheers, Wayne

 

[gene6]

Wyane Thank you for your comment the inspectors here read the code differently, as I am told these disconnects are "two different animals like deer and elk".
225.39 deals with the "feeder or branch-circuit disconnecting means" the location of that disconnect is governed by 240.21, the beginning of the feeder.
225.52 deals with an entirely different animal called a " building or structure disconnecting means".
The wording is clear even to a old fart like me.

 

[wwhitney]

225.39 deals with the "feeder or branch-circuit disconnecting means" the location of that disconnect is governed by 240.21, the beginning of the feeder.
225.52 deals with an entirely different animal called a " building or structure disconnecting means".

No. 225.39 is Part II "Buildings or Other Structures Supplied by a Feeder(s) or Branch Circuit(s)." 225.52 is in Part III "Over 1000 Volts."

So 225.52 only applies to feeders or branch circuits over 1000 volts. Both sections only refer to the disconnect at the building supplied, at the location specified in 225.32. Nothing in Article 225 speaks to the disconnect at the source end of the feeder or branch circuit.

Cheers, Wayne

 

[suemarkp]

225.31 says you need a feeder disconnect for the building. 225.32 tells you where it needs to be (at the remote building, nearest the entry of the conductors or on the outside of the bldg). 225.39 tell you how big that disconnect needs to be (60A).

The size of the feeder and the source breaker rating is determined by article 240, not 225. It can be less than the remote building disconnect rating.

 

[gene6]

Thank you all for your input 225.39 refers to the specifically to "feeder or branch-circuit disconnecting means" 240.21 requires that to be at the beginning of the feeder. 225.31 and .32 do not apply to the "feeder or branch-circuit disconnecting means".

 

[wwhitney]

Thank you all for your input 225.39 refers to the specifically to "feeder or branch-circuit disconnecting means" 240.21 requires that to be at the beginning of the feeder. 225.31 and .32 do not apply to the "feeder or branch-circuit disconnecting means".

No. The disconnecting means required by 225.31, in Part II of Article 225, is the subject of all the following sections 225.32 through 225.39. None of those speak to the OCPD required at the source of the feeder or branch-circuit disconnecting means, they speak only to the 225.31 disconnected, which is located as specified in 225.32. The context is 100% clear.

Also, 225.39 refers back to 225.33, which clearly refers to the 225.31 disconnect.

And if Article 225 wanted you to provide a minimum 60A feeder, it would say so directly, not indirectly by regulating the disconnecting means at the source of the feeder.

Lastly, 240.21 doesn't speak to disconnecting means at all, it speaks to overcurrent devices. Those could be fuses, which are not disconnecting means. And as specified in 225.36, the disconnecting means need not be an overcurrent devices. So don't conflate disconnecting means with overcurrent devices.

Cheers, Wayne

 

[jaggedben]

Yeah I agree with Wayne here. 240 requires overcurrent protection at the house. 225.39 requires a disconnect at the outbuilding rated 60A. The nonsense is that the disconnect rating requirement is larger than any other requirement in the code.

 

[don_resqcapt19]

Yeah I agree with Wayne here. 240 requires overcurrent protection at the house. 225.39 requires a disconnect at the outbuilding rated 60A. The nonsense is that the disconnect rating requirement is larger than any other requirement in the code.

The same language appears in Article 230 for services

 

[jaggedben]

The same language appears in Article 230 for services

Yeah, but that doesn't mean it makes sense.

 

[gene6]

Thank you all for your feedback.
I requested clarification today and this is what I got back:
A 2001 NEC code change proposal in part proposed to change the wording from “feeder or branch circuit” to “building or structure” disconnecting means.
The substantiation for the proposal was:
“The disconnecting means covered in this
section apparently refers to the building or structure disconnects of
Sections 225-31 through 225-39. Since supply conductors are
feeders and/or branch circuits, references to feeder or branch
circuit disconnecting means can be confusing and misleading as it
applies to the disconnects at the feeder or branch circuit source of supply.”

Had the CMP desired to clarify that they intended for the section to apply to the "building or structure disconnecting means" they would have accepted that proposal in some form.
In the end CMP-4 rejected the proposal entirely.
There have been other similar proposals over the years that have been rejected.

 

[wwhitney]

A 2001 NEC code change proposal in part proposed to change the wording from “feeder or branch circuit” to “building or structure” disconnecting means.

That would be 4-37 from the May 2001 ROP, PDF page 199. That proposal involved multiple changes to the 225-39, and was not restricted to the excerpt you mentioned. And the panel's rejection did not address this particular issue: "The proposed language is adding requirements that have not been adequately substantiated. The existing text is clear in stating the requirements for the rating of the disconnecting means."

As such, this rejection does not bear specifically on the terminological issue under discussion, and is therefore not relevant.

There have been other similar proposals over the years that have been rejected.

References to any of those would be appreciated. If you are just echoing responses you got from a third party, then the fact that the chosen example was PI 4-37 from May 2001 suggests that any other examples are even weaker.

Cheers, Wayne

 

[suemarkp]

The CMPs think much of their language is perfectly clear and not in need of update. But when they get multiple change proposals showing confusion, that should be an indication that their language is not clear.

 

[wwhitney]

That would be 4-37 from the May 2001 ROP, PDF page 199.

I started reviewing the PIs for code cycles subsequent to the above, and I came across PI 4-26 for the 2008 NEC cycle (and stopped there). The full text and committee response is below. But basically it was to add a Fine Print Note clarifying that 225.39 does not refer to the overcurrent device at the source of the feeder or branch circuit. The change was rejected as unnecessary, because that should already be clear.

Cheers, Wayne

4-26 Log #2194 NEC-P04 Final Action: Reject
(225.39, FPN )
______________________________________________________________
Submitter: David Williams, Lansing, MI
Recommendation: Revise as follows:
The rating feeder or branch-circuit disconnecting means shall have a rating of
not less than the load to be supplied, determined in accordance with Parts I and
II of Article 220 for branch circuits. Parts III or IV of Article 220 for feeders,
or Part V of Article 220 for farm loads. In no case shall the rating be lower
than specified in 225.39(A), (B), (C), or (D).
FPN: The rating of the overcurrent device protecting the feeder does not need
to be rated to the minimum rating in this section.
Substantiation: The code section specifies the minimum rating of the
disconnect and is not clear that the feeder or branch circuit needs to be rated
for this minimum rating. As an inspector, I am not positive if this section only
applies to the rating of the disconnect or does this mean that the minimum size
of a feeder to a building should be 60 amperes.
Just trying to clear up a concern.
Panel Meeting Action: Reject
Panel Statement: An additional FPN is not necessary. The title of 225.39
defines the requirement as solely being the rating of the disconnect.
Number Eligible to Vote: 10
Ballot Results: Affirmative: 10