Moble Home (2) Feeders

[boptrop]

Went to lady's mobile home this weekend. Electrician had upgraded the pole service from 100A to 200A with a Main breaker /feed through lugs and 4 slots on pole panel serving as disconnects & OCPDs.

Mobile home had a 100A panel in it witch electrician refed with 100A direct burial cable off the feed through lugs. Cable under trailer was tye wrapped to steel under trailer frame & not in conduit....I guess he is ok with the outside tap rule but no conduit?

Also found that a 100A underground feeder was feeding the AHU in the trailer from the pole panel. (100)A feeder breaker and cable to (2) 60A 2pole breakers in the AHU...also wrong? Didnt look at the wiring feeding the AHU but I am sure it was not in conduit either.

****Guess the main question I have is: can the pole disconnect/service provide (2) feeders to this mobile home? Or must all branch circuits that supply appliances in the mobile home be fed from 1 source within the trailer. The NEC uses terms such as: (A) panel implying only one feeder is allowed.

To top that off NM cable took the last slot in the pole panel...it was used to feed the CU sleeved with the direct burial cable to the underside of the mobile home then to a disconnect on the side of the trailer. No room left for breakers at the pole disconnect .....

Hacks at best

 

[Dennis Alwon]

Art. 550.32 disallows the service disconnect to be attached to the home . Then we have this that appears to allow the install

550.32(D) Additional Outside Electrical Equipment. Means for
connecting a mobile home accessory building or structure
or additional electrical equipment located outside a mobile
home by a fixed wiring method shall be provided in either
the mobile home service equipment or the local external
disconnecting means permitted in 550.32(A).

 

[Dennis Alwon]

Remember art. 1-4 are the general rules that can be modified by the other articles. In this case I believe 220.30 does not come into play as long as the equipment is outside the buiding

 

[boptrop]

The AHU is in the Middle of the mobile home, at floor level. It is being fed from the pole panel. In essence there are (2) feeders supplying the mobile home. The AHU is ~not outside the mobile home.

 

[Dennis Alwon]

The AHU is in the Middle of the mobile home, at floor level. It is being fed from the pole panel. In essence there are (2) feeders supplying the mobile home. The AHU is ~not outside the mobile home.

Okay I thought the feed was to the compressor not the inside unit. Yes this, IMO is a violation

 

[boptrop]

"Also found that a 100A underground feeder was feeding the AHU in the trailer from the pole panel."

Thanks,

 

[GoldDigger]

For NEC purposes, wires which are under the footprint of the building and not covered by concrete are NOT outside the building. So any tap would have a limited distance.

 

[Smart $]

For NEC purposes, wires which are under the footprint of the building and not covered by concrete are NOT outside the building. So any tap would have a limited distance.

Does the NEC specifically say that somewhere? Even if it does in an earlier chapter, not sure that would apply to a mobile home. Additionally, tap rules would only come into play if the feeder has an ampacity which is not considered protected by the supply OCPD.

 

[GoldDigger]

Does the NEC specifically say that somewhere? Even if it does in an earlier chapter, not sure that would apply to a mobile home. Additionally, tap rules would only come into play if the feeder has an ampacity which is not considered protected by the supply OCPD.

Well, specifically for mobile homes we have 550.15(H) which does not mention the distinction between inside and outside but does give requirements for wiring under the home.
230.6 specifies the condition I mentioned, but only for service conductors.
That leaves it open to interpretation whether a tap conductor under the building is inside or not.

 

[Smart $]

Well, specifically for mobile homes we have 550.15(H) which does not mention the distinction between inside and outside but does give requirements for wiring under the home.
230.6 specifies the condition I mentioned, but only for service conductors.
That leaves it open to interpretation whether a tap conductor under the building is inside or not.

I'd say it leaves a lot open to interpretation and debate. 550.15(H) is unclear in that it states in the title, "(Exposed to Weather)". If the mobile home has skirting, is the wiring exposed to weather? How do we determine when wiring is subject to physical damage? How do we weigh this requirement against any outside cable wiring method otherwise permitted to be exposed such as SE [338.10(B)(4)(b)]?

Service conductors should not even be at issue under a mobile home. Does Article 225 have any bearing?

I do not see where any conductor mentioned by OP is a tap conductor. Granted, he did not specify how a single cable terminates on the two 60A breakers in the AHU.

 

[boptrop]

"Mobile home had a 100A panel in it witch electrician re-fed with 100A direct burial cable off the feed through lugs." ----Meaning it is fed off the 200A service Main breaker....Feed through lugs typically come off the main bussing in the panel----(fully rated 200A OCPD). 100A mobile home wire rated at 100A would then be classified as a tap.

Also take a look at 550.14(H)--exposed to moisture..it shall be protected. There is no plastic covering the earth, hence exposed to moisture.

Anyway I have never seen Un-coverd twisted power conductors strung above the earth (except on poles or knobs around buildings, out of reach) under a mobile home before. Usually they are at least sleeved in conduit if not installed in conduit point to point.

 

[Dennis Alwon]

Anyway I have never seen Un-coverd twisted power conductors strung above the earth (except on poles or knobs around buildings, out of reach) under a mobile home before. Usually they are at least sleeved in conduit if not installed in conduit point to point.

This is without a doubt a violation

 

[Smart $]

"Mobile home had a 100A panel in it witch electrician re-fed with 100A direct burial cable off the feed through lugs." ----Meaning it is fed off the 200A service Main breaker....Feed through lugs typically come off the main bussing in the panel----(fully rated 200A OCPD). 100A mobile home wire rated at 100A would then be classified as a tap.

That is correct. Missed that correlation in the OP... and I thought you were referring to the AHU feeder, not the Panel feeder, as a tap.

Also take a look at 550.14(H)--exposed to moisture..it shall be protected. There is no plastic covering the earth, hence exposed to moisture.

Yes... but 550.15(H) title says "(Exposed to Weather)", which leaves it open to interpretation. Is under a mobile home, especially one with skirting, exposed to weather? Or is it saying all under chassis wiring is to be considered exposed to weather or physical damage? Just asking, because I would prefer to see it in raceway... at least a chase, not necessarily complete raceways.

Anyway I have never seen Un-coverd twisted power conductors strung above the earth (except on poles or knobs around buildings, out of reach) under a mobile home before. Usually they are at least sleeved in conduit if not installed in conduit point to point.

I agree with Dennis. There is no un-jacketed cable type permitted to be run exposed except overhead.

 

[boptrop]

I should have stated the direct bury cable was the URD type, Twisted uncovered power conductors, some people call it mobile home sub feed cable, some call it URD, I think it is RHHW insulation or something 4plex twisted with no outer jacket 4/0-4/0-2/0-6. Typical for residential feeds...I have never seen any other direct bury cables that are that large so, I assumed everyone would know what I was talking about....sorry about that.

I guess it is the consensus about the multiple feeders from the pole service to the mobile home is clearly a violation as well?

 

[RB1]

I have always interpreted 550.15(H) "Under-Chassis Wiring (Exposed to the Weather)" to require either rigid metal, IMC, or Schedule 80 PVC for any wiring installed below the chassis of the home regardless of the presence of a skirt. The exception permitting other wiring methods where closely routed against the frame.

The feeder cable you described is likely an underground service entrance cable and is not permitted for use above ground unless protected in accordance with 300.5. A flame retardant covering is required for termination inside the home (the cable described is probably dual listed). Additionally, feeder tap conductors are generally required to be protected by raceways.

Section 550.10(A) permits not more than one permanently installed feeder as the source of supply for the home.

 

[boptrop]

Additionally, feeder tap conductors are generally required to be protected by raceways.

I guess this goes back to weather under the foot print is still considers a outside feeder tap. But it is kind of a moot point because of the other reasons listed.

Anyway gave the inspector a heads up that the lady will be calling for a inspection (only service equipment is inspected in this area unless requested) for the instillation and he said he can cite on paper the violations for her. She hasn't paid the contractor and he took her to court. I guess it recessed until I (electrician) looked at it and a inspector looked at it.

I looked the guys licensing up on the website for the state and he was a licensed electrician and HVAC installer as well as plumber , carpenter and so on. I don't know how one could be a expert at all those trades. I guess grandfathered licensing? This one sure does seem to be a hack at electrical work though.

Hopefully the judge will see it that way and tell that contractor the she owes him nothing...time will tell.

As a side note - while talking to the inspector he said that he had seen this before in the area and the 4plex had been spliced (free air) with ronmex (NM) connectors as the splicing device.
He didn't have any pictures though.....makes you wonder what people are thinking.

 

[Smart $]

I have always interpreted 550.15(H) "Under-Chassis Wiring (Exposed to the Weather)" to require either rigid metal, IMC, or Schedule 80 PVC for any wiring installed below the chassis of the home regardless of the presence of a skirt. The exception permitting other wiring methods where closely routed against the frame.

The subsection conditions have been eliminated in 2014 edition to require a wet-location approved conduit or raceway, regardless of routing.

The feeder cable you described is likely an underground service entrance cable and is not permitted for use above ground unless protected in accordance with 300.5. A flame retardant covering is required for termination inside the home (the cable described is probably dual listed). Additionally, feeder tap conductors are generally required to be protected by raceways.

Agree.

Section 550.10(A) permits not more than one permanently installed feeder as the source of supply for the home.

Agree. Sounds like mobile home was manufactured with gas- or oil-fired furnace and converted to electric... for which OEM panel is underrated.

Now I'm wondering... :blink:

I know the disconnecting means is not permitted to be on or in the mobile home... but what if a 200A feeder were run from the remote disconnecting means to an exterior-mounted disconnect switch, and load side was tapped to OEM panel (assuming it is MCB) and AHU (double tapped because furnace has two 60A breakers). Would that be compliant?

 

[boptrop]

I would think it would be because at that point it would be a part of the mobile home and would go with the mobile home if it is moved.....It then would become (by preference of material*) the main panel* for the home and the old panel would be a sub fed panel. Even using taps and proper tap rules from a disconnect it would be compliant. I think the intent is to not have to disconnect the trailer from more than one source when it is being relocated and also for safety, Most people that have a panel in/on their dwelling usually think that if that is off everything would be off.....

 

[Smart $]

I would think it would be because at that point it would be a part of the mobile home and would go with the mobile home if it is moved.....It then would become (by preference of material*) the main panel* for the home and the old panel would be a sub fed panel. Even using taps and proper tap rules from a disconnect it would be compliant. I think the intent is to not have to disconnect the trailer from more than one source when it is being relocated and also for safety, Most people that have a panel in/on their dwelling usually think that if that is off everything would be off.....

I agree with your reasoning... and exactly why I brought it up.

 

[frankft2000]

Is this structure really a "mobile home" or is it a "manufactured home"? There is a big difference in the two, and mobile homes have not been manufactured since 1978.