seperate structure grounding

[mayor43822]

My customer has set a new double wide home on a crawl space . Service
was built on a pole within 30 ft. of home and grounded at pole and an
additional uferground from footer was ran back to service at pole .
Feeder to home is four wire , local inspecter wants an additional ground wire from electrical panel in home connected to ufer , there reason for this is they are considering the home a seperate structure and would require an
additional ground , following 550.32 for service placement would you be
required to call it a seperate structure and add the additional connection
to the ufer ?

 

[Bea]

grounding electrode is required to be connect to the service disconnect or feeder disconnect if the service disconnect is more than 30 feet from MH. No electrode is required to be connect to the MH load center.

 

[Smart $]

Calling the home a separate structure IMO is a stretch...

...but there are many that see it the same way as your inspector. Debatable, yes... but it's probably one you shouldn't take to a formal level

 

[Dennis Alwon]

article 550.32 states that the service disco. cannot be more than 30' from the trailer. It also states to follow 250.32. I agree with the inspector on this one.

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.

 

[raider1]

Calling the home a separate structure IMO is a stretch...

How is it a stretch?

The service for the home is 30' away on a pole. The pole and service meet the definition of structure from Article 100. Therefore the home is another structure separated from the pole by 30 feet.

By the way I agree with Dennis. 550.32(A) makes it clear that the disconnecting means for the mobile home must be grounding in accordance with 250.32, which is titled "buildings or structures supplied by a feeder(s) or branch circuit(s)".

Chris

 

[Dennis Alwon]

My customer has set a new double wide home on a crawl space . Service was built on a pole within 30 ft. of home and grounded at pole and an additional uferground from footer was ran back to service at pole .

You could have added 2 ground rods at the pole but I believe what you did was, perhaps, better.

Feeder to home is four wire , local inspecter wants an additional ground wire from electrical panel in home connected to ufer , there reason for this is they are considering the home a seperate structure and would require an additional ground , following 550.32 for service placement would you be required to call it a seperate structure and add the additional connection to the ufer ?

I answered this already but will reiterate that, IMO, you are required to run the gec to the main panel in the trailer. You could simply split bolt the a #4 wire from the panel to the ufer.

 

[billsnuff]

i have done both. both manuf homes, two different jurisdictions (read POCO).
one in 2008 under the 05 NEC w/ no inspection and one in 2009 under the )* NEC w / inspection required it passed and the inspector look for both sets of rods. So I agree with the rest, seperate structure.

 

[Smart $]

How is it a stretch?

The service for the home is 30' away on a pole. The pole and service meet the definition of structure from Article 100. Therefore the home is another structure separated from the pole by 30 feet.

The pole does not meet the defintion of a structure, i.e. a wood pole. Last time I checked :grin: wood is grown. Yes a pole is modified in shape from a tree, but that still does not qualify it as being built or constructed. At best, it is placed or erected, but definitely not built or constructed. This is the very reason 550.32(A) addresses the issue.

If you put some sort of backer board on the pole, then it qualifies if you really want to be that anal.

If you consider adding the electrical equipment to it thus qualifies it as built or constructed, then that would be a paradox for the requirement, because anything you attach electrical equipment to thus becomes built or constructed.

All the same, I'm not going to argue on this aspect, because the additional grounding makes it at least a little safer.

By the way I agree with Dennis. 550.32(A) makes it clear that the disconnecting means for the mobile home must be grounding in accordance with 250.32, which is titled "buildings or structures supplied by a feeder(s) or branch circuit(s)".

I don't agree that it makes it clearer as it specifically says grounding at the service disconnect, not the panel in the mobile home. Upon going to 250.32, you can only take it in the context of service disconnecting means grounding. Additionally, as we all know, Chapter 5 amends 1 thru 4, so the fact that grounding is addressed does amend other grounding requirements in Chapters 1 thru 4.

 

[Bea]

Quote:
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

This code reference is refering to the disconnect located not more than 30 feet from the Mobile Home and not in or on the mobile home.

As I stated earlier no gounding electrodes are required to be connect to the load center in or on a mobile home. Unless this is a modular Home I am missing your guys piont please enlighten me.

 

[Smart $]

As I stated earlier no gounding electrodes are required to be connect to the load center in or on a mobile home. Unless this is a modular Home I am missing your guys piont please enlighten me.

I am of the impression it is a manufactured home but not wired under 550.32(B).

The OP'er will have to chime in and confirm...

 

[mayor43822]

Thanks everyone for your replies , to answer your question Smart $ , yes
this is a manufactured home on a crawl which allows it to have its
service either on the home or as it was done on a pole . Thanks again .

 

[RB1]

Dennis,

The requirement to comply with 250.32 is applicable only where the service equipment is located more than 30 feet away from the manufactured home and an additional disconnect is required within within 30 feet of the home. The additional disconnect is considered a separate structure from the service equipment. This makes since because there is no limitation to the distance between the service equipment and the additional disconnecting means. I think this first appeared in the 1999 Code.

 

[Smart $]

Dennis,

The requirement to comply with 250.32 is applicable only where the service equipment is located more than 30 feet away from the manufactured home and an additional disconnect is required within within 30 feet of the home. The additional disconnect is considered a separate structure from the service equipment. This makes since because there is no limitation to the distance between the service equipment and the additional disconnecting means. I think this first appeared in the 1999 Code.

Doesn't matter whether the service equipment is located more than 30 feet away or within 30 ft away, because it is always the disconnecting means located within 30 ft which is to have grounding in accordance with 250.32.

 

[RB1]

Prior to the 1999 Code, the requirement for compliance with 250-24 (now 250.32) applied to the feeder disconnecting means that was located within 30feet of the home by the exception that permitted the service disconnecting means to be located elsewhere on the premises. I interpret the last sentence of 550.32(A) of the 2008 Code to mean the same thing. This is the required disconnecting means for the structure (the modular home). This is a case where Chapter 5 has modified the requirements of 225.32 by permitting the disconnecting means for this structure to be located up to 30 feet away. The disconnecting means, even though it is 30 feet away, is part of the structure it serves.

 

[Dennis Alwon]

With the definition of structure, as it stands today, there is a whole lot to be desired. If I consider the pole a structure then I must comply with art.250.56
if I am using rods.

We have been around the block a thousand times on this one and it is obvious that there are two schools of thought about what constitutes a structure.

If I have a mobile home and the trailer disco was 30 feet away, I would want a rod closer to the source of what I am protecting. Of course, there are 2 schools of thought as to whether or not a rod is worth anything.

The OP is using a Ufer so just bug on to the wire and tie it to the panel. You can't lose. I would rather have mu ufer at the house then out at the pole.

RBI-- 550.32 does require bonding at the disconnect means. Which one? The manufactured home still would need a disconnecting means on or within the structure (art.550.11(A)).

 

[RB1]

Dennis,

I agree that the OP's installation is a good idea. I don't believe it is required by Code. Prior to the exceptions being converted to positive code text, this section required the grounding electrode connection to be made at the disconnecting means located within 30 feet of the mobile home. I think is because historically mobile homes would not have offered many beneficial grounding electrodes. The grounding electrode system and connection would be a part of the infrastructure of the park.

But then again, the times are a changin.

 

[Smart $]

...550.32 does require bonding at the disconnect means. Which one? The manufactured home still would need a disconnecting means on or within the structure (art.550.11(A)).

The one mentioned in the preceding sentences of 550.32, of course.

 

[Bea]

this is a manufactured home on a crawl which allows it to have its
service either on the home or as it was done on a pole . Thanks again .

Just because it is on a crawl does not permit it to it have its service in or on it. It has to come from the manufacture designed that away with specific instruction and in most cases would not be permitted to be supplied by a feeder as the service equipment installed in or on the mobile would be a meter main marked suitable for use as service equipment only.

 

[hillbilly]

Just because it is on a crawl does not permit it to it have its service in or on it. It has to come from the manufacture designed that away with specific instruction and in most cases would not be permitted to be supplied by a feeder as the service equipment installed in or on the mobile would be a meter main marked suitable for use as service equipment only.

Beg to differ.

If it's a Manufactured Home, it is allowed to locate the electrical service on the side of the home....every one that I've seen or installed anyway.

It doesn't require a Meter Main either.
A simple Meter base with a Main Disconnect mounted beside it will suffice.
It is required for the Main to be located outside the structure.

The distiction is between a Manufactured Home and a Mobile Home.

Mobile Homes and Manufactured homes are both supplied by feeders.
The difference is where the Main Disconnect can be located.

I've never seen a specification from a manufactured home that says anything about the electrical service location.
That's usually decided by the POCO with input from the electrician who's doing the work.

Just my opinion.
steve