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Posted By: Yoopersup Art. 550 Manufactured homes services - 04/05/05 03:41 PM
Article 550.32 (b)(3) means shall be provide for the connection of a grounding Conductor to the service equipment and routing it OUTSIDE the structure.
As Most if not all Manufactured homes require a 4 wire FEEDER . Yet code says inside IF meets provisions.??? How can this section be complyed with if a Disconnect is not installed out side the Unit. Are any Manufactured homes wired with a 3 wire with the service inside and grounding Electroid conductors brought there???
Posted By: Tom Re: Art. 550 Manufactured homes services - 04/05/05 08:43 PM
I have never personally seen a manufactured home with the service equipment installed inside by the manufacturer. Every one that I've inspected required a 4 wire feeder with the service disconnecting means outside.

550.32(B)(3) can be complied with by installing a PVC raceway from the panel to an accessible location outside the home.

Since the manufacturer would have to comply with 7 steps in order to put the service equipment inside, I don't think too many of them are going to bother.

Another problem with the inside panel being the service disconnect is that it would frequently be in the wrong place. This isn't a problem with the outside disconnect & 4 wire feeder.

Tom
Posted By: gfretwell Re: Art. 550 Manufactured homes services - 04/05/05 09:47 PM
I agree with Tom. The state set up a bunch of different types of manufactured buildings while I was working for them and the manufacturers all specified a 4 wire feeder and an external disconnect.
Posted By: Alan Nadon Re: Art. 550 Manufactured homes services - 04/06/05 03:09 AM
This was put into the Code because one manufacturer on the East coast built a manufactured community. He designed the entire thing, and to reduce cost installed the service equipment on the homes. He knew exactly where the service / utility location was for each lot and set the service accordingly. Everything including the meter socket was built on the home and inspected and shipped that way.
HUD allows the meter socket to be put on in the field, because of different utility companies. HOWEVER, installing the service on a home in the field after it has had the HUD label applied is a field conversion and is NOT covered by the HUD label.
The few homes manufactured to the 3 wire system present a problem in the factory when they are high pot tested, i.e. high voltage applied to detect insulation damage, since the neutral is bonded at the home the entire frame and anything connected is energized. Zap the plumber, and the siding man.
It is important to note that manufactured homes that have a label OTHER THAN HUD may be built to the same building code that governs stick built housing and as a result will have a three wire service on them. These are usually inspected and labeled by the State Building Dept.
THE TYPE OF LABEL IS VERY IMPORTANT. Putting a HUD home on a permanent foundation DOES NOT CHANGE the labeling, or change it from a four wire to a three wire service.
HUD rules are based on an act of Congress NOT the NEC. I think they are currently required to comply with the 1993 Code with exceptions that allow panels in closets.
Locally we have four wide units, and two story units, with attached garage. The garage is a good place to mount the service with a feed through panel because it makes it look like a stick built home.
Alan from Elkhart the MH/RV capitol of the midwest.
As one wag said Mobile homes are like drugs. It's OK to sell them but, don't use them.

[This message has been edited by Alan Nadon (edited 04-05-2005).]
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