310.15(b)(6)

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jwelectric

Senior Member
Location
North Carolina
Mobile VS Manufactured.

In 550.2 it said that they are basically the same. Unless otherwise indicated.

550.32 is one of those examples.

I have no problem with 550.33(B).

Manufactured Home. A structure, transportable in one or more sections, that, in the traveling mode, is 2.4 m (8 body-ft) or more in width or 12.2 m (40 body-ft) or more in length, or, when erected on site, is 29.7 m2 (320 ft2) or more and that is built on a permanent chassis and designed to be used as a dwelling, with or without a permanent foundation, when connected therein. The term manufactured home includes any structure that meets all the provisions of this paragraph except the size requirements and with respect to which the manufacturer voluntarily files a certification required by the regulatory agency, and except that such term does not include any self-propelled recreational vehicle. Calculations used to determine the number of square meters (square feet) in a structure are based on the structure's exterior dimensions, measured at the largest horizontal projections when erected on site. These dimensions include all expandable rooms, cabinets, and other projections containing interior space but do not include bay windows.

For the purpose of this Code and unless otherwise indicated, the term mobile home includes manufactured homes.

FPN No. 1: See the applicable building code for definition of the term permanent foundation.

FPN No. 2: See Part 3280, Manufactured Home Construction and Safety Standards, of the Federal Department of Housing and Urban Development, for additional information on the definition.

Mobile Home. A factory-assembled structure or structures transportable in one or more sections that are built on a permanent chassis and designed to be used as a dwelling without a permanent foundation where connected to the required utilities and that include the plumbing, heating, air-conditioning, and electrical systems contained therein.

For the purpose of this Code and unless otherwise indicated, the term mobile home includes manufactured homes.

Where are you getting the requirement that these two are separated in some way? Look at the underlined section of the definition of Manufactured Home and it is clear that HUD can label a single wide as a manufactured home.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
Mike

As I have stated 550.32.

(A) Mobile
(B) Manufactured

Using (B) I could supply my manufactured home with a H-H-N without an outside disconnect. I could not do this to my mobile home.
 

jwelectric

Senior Member
Location
North Carolina
Mike

As I have stated 550.32.

(A) Mobile
(B) Manufactured

Using (B) I could supply my manufactured home with a H-H-N without an outside disconnect. I could not do this to my mobile home.


So let me ask you a simple question.

If I had a single wide mobile home that had all the information found in 550.32(B) sent with it could I mount the meter to the side of this mobile home?
 

newinspector1

Member
Location
NC
Sorry it took so long to get back up here. This is a modular built in accordance with the residential code. Dennis there is two panels. The outside is a meter/panel combo with 4/0 mobile home feeder going to the inside panel. The a/c is wired to the outside is this legal or am I correct that nothing can go to the outside panel unless the breaker is downsized acoording to 310.16.
 

jumper

Senior Member
Sorry it took so long to get back up here. This is a modular built in accordance with the residential code. Dennis there is two panels. The outside is a meter/panel combo with 4/0 mobile home feeder going to the inside panel. The a/c is wired to the outside is this legal or am I correct that nothing can go to the outside panel unless the breaker is downsized acoording to 310.16.

I believe that the 4/0 AL is now only good for 180 amps, so either the guy needs to change the breaker or run new wire.

I think T310.15(B)(6) no longer applies.
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
Sorry it took so long to get back up here. This is a modular built in accordance with the residential code. Dennis there is two panels. The outside is a meter/panel combo with 4/0 mobile home feeder going to the inside panel. The a/c is wired to the outside is this legal or am I correct that nothing can go to the outside panel unless the breaker is downsized acoording to 310.16.

That changes things. Now what we have is a wire feeding a sub panel and assume a 200 amp breaker and the wire between them if 4/0 alum is only good for 180.
As for the panel at meter if it is a 200 amp with feed thru and a few openings for other breakers such as AC,water pump, pool, hot tub, shed,etc I see no issues with it.
Problem is the wire feeding the inside panel should be 250 and is good for 205 amps.
Really is no chance of that panel reaching anything like 200 amps. most likely never see 100 amps.
In my opinion let it go as your creating an unneeded cost to solve nothing. Perhaps the easy fix is change breaker to a 150 but that now puts him in a likely bad spot because his contract probably stated 200 amp service. Is there a breaker higher than 100 that could fit this outside panel and use it to feed inside panel.
You could request and should to see a new total load calc for the home with the AC. Chances are very good that it will not be even near 150 amps.
Really up to you as the AHJ to make the call.
 
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Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Sorry it took so long to get back up here. This is a modular built in accordance with the residential code. Dennis there is two panels. The outside is a meter/panel combo with 4/0 mobile home feeder going to the inside panel. The a/c is wired to the outside is this legal or am I correct that nothing can go to the outside panel unless the breaker is downsized acoording to 310.16.

The fact is if the 4/0 mobile home wire is in conduit then I do not see an issue as long as the calculated load is 180 amps or less. 240.4(B) allows us to use the next size breaker so the feeder should be compliant on a 200 amp breaker.

If this were ser cable I would say no go.
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
The fact is if the 4/0 mobile home wire is in conduit then I do not see an issue as long as the calculated load is 180 amps or less. 240.4(B) allows us to use the next size breaker so the feeder should be compliant on a 200 amp breaker.

If this were ser cable I would say no go.

Good point, I overlooked that
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
So let me ask you a simple question.

If I had a single wide mobile home that had all the information found in 550.32(B) sent with it could I mount the meter to the side of this mobile home?

No. It (the unit) is either a mobile home or a manufactured home (from the factory).

I believe that the 4/0 AL is now only good for 180 amps, so either the guy needs to change the breaker or run new wire.

I think T310.15(B)(6) no longer applies.

You are not correct. Please tell me why the table does not apply.

That changes things. Now what we have is a wire feeding a sub panel and assume a 200 amp breaker and the wire between them if 4/0 alum is only good for 180.
As for the panel at meter if it is a 200 amp with feed thru and a few openings for other breakers such as AC,water pump, pool, hot tub, shed,etc I see no issues with it.
Problem is the wire feeding the inside panel should be 250 and is good for 205 amps.
Really is no chance of that panel reaching anything like 200 amps. most likely never see 100 amps.
In my opinion let it go as your creating an unneeded cost to solve nothing. Perhaps the easy fix is change breaker to a 150 but that now puts him in a likely bad spot because his contract probably stated 200 amp service. Is there a breaker higher than 100 that could fit this outside panel and use it to feed inside panel.
You could request and should to see a new total load calc for the home with the AC. Chances are very good that it will not be even near 150 amps.
Really up to you as the AHJ to make the call.

550.33(B).

The fact is if the 4/0 mobile home wire is in conduit then I do not see an issue as long as the calculated load is 180 amps or less. 240.4(B) allows us to use the next size breaker so the feeder should be compliant on a 200 amp breaker.

If this were ser cable I would say no go.

http://forums.mikeholt.com/showthread.php?t=86929&page=3
 

jumper

Senior Member
The fact is if the 4/0 mobile home wire is in conduit then I do not see an issue as long as the calculated load is 180 amps or less. 240.4(B) allows us to use the next size breaker so the feeder should be compliant on a 200 amp breaker.

If this were ser cable I would say no go.

Good point, I overlooked that

Dennis that is what I ended up doing. Thanks for the help.

Aw man, there is just something wrong about a guy passing inspection, when he seems to have screwed up and got lucky.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
310.15(B)(6) table applies under the conditions of art. 310.15(B)(6). Art. 550.33(B) is talking about art. 310.15(B)(6) not just the Table so technically Jim is correct. The table would not apply if the a/c load is in the main panel.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Aw man, there is just something wrong about a guy passing inspection, when he seems to have screwed up and got lucky.

Maybe he knew what he was talking about. Believe it or not, there are contractors out there that know what they are doing.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
310.15(B)(6) table applies under the conditions of art. 310.15(B)(6). Art. 550.33(B) is talking about art. 310.15(B)(6) not just the Table so technically Jim is correct. The table would not apply if the a/c load is in the main panel.

Thanxs Dennis.

For some reason I went to the table and totally forgot that all of 310.15(B)(6) applies.

I'll review it later to see if anything that I have said is incorrect.
 
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jumper

Senior Member
Mike that is my question because I don't think that it is supplying the entire load. There is no pole this is a modular home with a service on the house. The electrician ran mobile home feeder and said that got him out of having to downsize his breaker.

Maybe he knew what he was talking about. Believe it or not, there are contractors out there that know what they are doing.

Dennis, the quote above yours seems to imply that this particular EC got lucky. It seems to imply that that the EC felt that if "mobile home feeder "was run he/she could apply T310.15(B)(6) to a feeder that does not carry the whole dwelling load.

I am more than willing to admit that I may be wrong, yet can you see how I could interpet this.

I, in no way, think all Ecs are ignorant.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Dennis, the quote above yours seems to imply that this particular EC got lucky. It seems to imply that that the EC felt that if "mobile home feeder "was run he/she could apply T310.15(B)(6) to a feeder that does not carry the whole dwelling load.

I didn't read it that way simply because that makes no sense but who knows. Why would running a mobile home feeder allow you to use T. 310.15(B)(6)??? In conduit it works... I gave him the benefit of the doubt but....

It doesn't really matter anyway since we probably won't ever know what he was thinking.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
Thanxs Dennis.

For some reason I went to the table and totally forgot that all of 310.15(B)(6) applies.

I'll review it later to see if anything that I have said is incorrect.

I have not read all my previous posts but I know that I stated earlier that the 100% load did not come in to play. I was wrong on that.
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
Seems that even if 310.15 did not fly he still was ok because there is no 180 amp breaker so he can use a 200
And seriously what are the chances of a modular home hitting 200 amps. Takes some strange loads like i have at my parties to hit that
 
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