mobile home & ground rods

[luckyshadow]

ok- I'm following a thread on another site. The question is coming down to: Is it required to install a ground rod at a mobile home?
Service will be on a pole within 30 feet of moile home. The 2 parties agree the service is on the pole and rods are required there. The one fellow says a ground rod is required at the mobile home as well. He is saying it is covered by 250.32 Building or Structures Supplied by a Feeder.

What is everyones thoughts, seperate structure ? Ground Rod required ?

 

[iwire]

It is a separate building or structure.

It has a feeder running to it.

A grounding electrode system of some type must be present at the separate building or structure.

 

[kbsparky]

No ground rods required for a mobile home. At the service, yes, but not at the actual trailer.

Section 550.10 outlines the requirements for mobile home feeders and connection. No where does it require any ground rod, or grounding electrode systems.

Section 550.16 outlines the grounding requirements for mobile homes.

Section 550.32 outlines the service equipment requirements for mobile homes. It should be noted that grounding as per section 250.32 is required at the disconnecting means

 

[david]

550.16 Grounding.
Grounding of both electrical and nonelectrical metal parts in a mobile home shall be through connection to a grounding bus in the mobile home distribution panelboard. The grounding bus shall be connected through the green-colored insulated conductor in the supply cord or the feeder wiring to the service ground in the service-entrance equipment located adjacent to the mobile home location. Neither the frame of the mobile home nor the frame of any appliance shall be connected to the grounded circuit conductor in the mobile home. Where the distribution panelboard is the service equipment as permitted by 550.32(B), the neutral conductors and the equipment grounding bus shall be connected.

 

[iwire]

No ground rods required for a mobile home. At the service, yes, but not at the actual trailer.

Section 550.10 outlines the requirements for mobile home feeders and connection. No where does it require any ground rod, or grounding electrode systems.

Section 550.16 outlines the grounding requirements for mobile homes.

I am not saying you are wrong but can you show me which section of either article tells us 250 does not apply?

90.3 Code Arrangement. This Code is divided into the
introduction and nine chapters, as shown in Figure 90.3.
Chapters 1, 2, 3, and 4 apply generally; Chapters 5, 6, and 7
apply to special occupancies, special equipment, or other special
conditions. These latter chapters supplement or modify the
general rules..............

 

[david]

There must be confusion in the discussion between manufactured buildings 545.11 and manufactured homes 550.16

 

[kbsparky]

Sorry, I added another section after you posted it would appear. Section 550.32 requires grounding as per section 250.32 at the disconnecting means. It does not require further grounding at the trailer itself, as long as the feeders are properly installed and identified

 

[iwire]

Sorry, I added another section after you posted it would appear. Section 550.32 requires grounding as per section 250.32 at the disconnecting means. It does not require further grounding at the trailer itself, as long as the feeders are properly installed and identified

I read the section and if the service disconnect is 'elesewhere' you are required to add another disconnecting means near the trailer and that added disconect must be grounded per 250.32.

I still see nothing that says 250.32 does not apply to the trailer / home etc.

550.32 Service Equipment.
(A) Mobile Home Service Equipment. The mobile home
service equipment shall be located adjacent to the mobile
home and not mounted in or on the mobile home. The
service equipment shall be located in sight from and not
more than 9.0 m (30 ft) from the exterior wall of the mobile
home it serves. The service equipment shall be permitted to
be located elsewhere on the premises, provided that a disconnecting
means suitable for use as service equipment is
located within sight from and not more than 9.0 m (30 ft)
from the exterior wall of the mobile home it serves and is
rated not less than that required for service equipment per
550.32(C). Grounding at the disconnecting means shall be
in accordance with 250.32.

 

[david]

ok- I'm following a thread on another site. The question is coming down to: Is it required to install a ground rod at a mobile home?
Service will be on a pole within 30 feet of moile home. The 2 parties agree the service is on the pole and rods are required there. The one fellow says a ground rod is required at the mobile home as well. He is saying it is covered by 250.32 Building or Structures Supplied by a Feeder.

What is everyones thoughts, seperate structure ? Ground Rod required ?

The question is when the service is on a pole within 30 ft, does 250.32 require a ground rod at the home. It is clear that 550.32 says no.
550.16 n0t 550.32

 

[renosteinke]

An interesting situation.

I've never thought to drive an additional rod for the trailer itself, considering the rod at the pedestal to be enough.

To be fair, I've never encountered such an additional rod, either.

I have had to re-wire a mobile home, and their construction is such that running an additional GEC to an additional rod is not encouraged at all. With the simple panelling 'wall' glued to the studs, repairing the hole you'd have to make is no simple matter.

I do recall that the frame was bonded to the bussbar. Would it be enough to land a GEC from the rod on a beam clamp to the frame? I'm not too excited about that idea.

Another detail that might apply is the method of anchoring the trailer. They seem to be anchored by driving multiple 4' stakes into the ground ... would those qualify as 'made electrodes?' From an engineering perspective, that network of anchors should be nearly as effective as any Ufer.

From a 'wordsmith' perspective, I have an issue with calling the trailer a 'separate structure.' It's the ONLY structure; I don't see hiow the pedestal itself can be called a 'structure.' The wording in 250 seems to assume that the service is part of a building, rather than a stand-alone pedestal.

 

[iwire]

The question is when the service is on a pole within 30 ft, does 250.32 require a ground rod at the home. It is clear that 550.says no.
550.16 n0t 550.32

Thanks, 550.16 indicates we can ignore 250.32 and I believe that is the intent but I do not see the words that allow it.

 

[kbsparky]

I see nothing that requires any further grounding at the mobile home itself.

You stated yourself that the grounding shall be at the disconnecting means. I agree. If grounding was required at the mobile home, it would have said so in article 550.

You have already stated that chapter 5 can supercede things in chapter 3. Again I agree.

So why are you arguing with this?

 

[kwired]

I figured the reason the disconnect must be within 30 feet of the mobile home was it was considered a necessary part of the mobile home - just happens to be field installed.

All other buildings or structures must have disconnect or service in, on or at least immediately adjacent to the building or structure. This is only place where it specifically states a specific distance from the structure served that I am aware of.

I could be wrong.

 

[iwire]

I see nothing that requires any further grounding at the mobile home itself.

Because there is nothing in 550 that tells us that 250.32 does not apply to a mobile home.

Becuse there is no excpetion in 250.32 that says 'except for a mobile home'

You stated yourself that the grounding shall be at the disconnecting means.

Yes, the grounding for that disconnecting means.

If grounding was required at the mobile home, it would have said so in article 550.

That would be redundant, 250.32 already tells us it is required.


You have already stated that chapter 5 can supercede things in chapter 3. Again I agree.

So why are you arguing with this?

Because I disagree with a lot that has been posted.

 

[frankft2000]

How old is this "mobile home". **Trick question alert**

 

[hurk27]

How old is this "mobile home". **Trick question alert**

What the trick, after June 16 1986 it falls under HUD rules CFR 24 3280.800 before it falls under NEC unless your state refers it over to HUD.

See no trick to it at all

 

[david]

Federal Department of Housing and Urban Development, has jurisdiction over manufactured homes. The manufacture sends instructions on how these are to be supplied.. The only thing electrically that can be inspected is the service equipment and or the feeder to the home. No-one can require anything to be connected to one unless the manufacture has given instructions to do so.

You also have to be certified to install one. You even need additional certification yo inspect anything associated with one.

I never seen anything in any instruction requiring an additional ground rod at one.

 

[hurk27]

Federal Department of Housing and Urban Development, has jurisdiction over manufactured homes. The manufacture sends instructions on how these are to be supplied.. The only thing electrically that can be inspected is the service equipment and or the feeder to the home. No-one can require anything to be connected to one unless the manufacture has given instructions to do so.

You also have to be certified to install one. You even need additional certification yo inspect anything associated with one.

I never seen anything in any instruction requiring an additional ground rod at one.

Correct

 

[kwired]

Federal Department of Housing and Urban Development, has jurisdiction over manufactured homes. The manufacture sends instructions on how these are to be supplied.. The only thing electrically that can be inspected is the service equipment and or the feeder to the home. No-one can require anything to be connected to one unless the manufacture has given instructions to do so.

You also have to be certified to install one. You even need additional certification yo inspect anything associated with one.

I never seen anything in any instruction requiring an additional ground rod at one.

Manufactured homes or mobile homes (or both). I always thought it was just mobile homes.

Next question is other than a new mobile home, who actually inspects anything to HUD standards once it is been placed in the field?

 

[Dennis Alwon]

I personally believe that the rods are needed but you can use the rods that are at the pole. The trailers I see around here, the pole is located within 5 feet of the home. This would make using those rods easier. Anyone see a problem with that.