Distance allowedof feeder inside

[spudley]

Feeder distance allowed inside bldg before breaker panel

Does the NEC prohibit an 11' run inside a building before the feeder enters the breaker panel?

I'd like to enter my detached building near the corner closest to the house panel.

I'm using MHF in scd 40 conduit, with sch 80 coming out of the ground to an LB.
Inside, I'd then run 11' of scd 80 behind a stairway to the panel which will have the requisite access spacing as the stairway rises.

If I trench to the area directly behind this panel location, I have a buried gas line to deal with.

I'm hanging the panel this weekend so any thoughts?

 

[john8791]

Here are some NEC (2011 anyway) requirements. There doesn't seem to be a hard length requirement, only that "The disconnecting means shall be at a readily accessible location nearest the point of entrance of the conductors."

225.31 Disconnecting Means.
Means shall be provided for disconnecting all ungrounded conductors that supply or pass through the building or structure.

225.32 Location.
The disconnecting means shall be installed either inside or outside of the building or structure served or where the conductors pass through the building or structure. The disconnecting means shall be at a readily accessible location nearest the point of entrance of the conductors. For the purposes of this section, the requirements in 230.6 shall be utilized.

225.33 Maximum Number of Disconnects.
(A) General. The disconnecting means for each supply permitted by 225.30 shall consist of not more than six switches or six circuit breakers mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be no more than six disconnects per supply grouped in any one location.

 

[mm08822]

It's up to your inspector.

In my area, 6 ft is the unspoken limit but there is nothing "written" about this length. Typically, it is the shortest path from point of entry to the ocp device.

Your scenario would not pass for me.

Either relocate the point of entry or add a main disconnect on the exterior.

 

[PCustoms]

Is this a subpanel fed from your house?

 

[spudley]

It's up to your inspector.

In my area, 6 ft is the unspoken limit but there is nothing "written" about this length. Typically, it is the shortest path from point of entry to the ocp device.

Your scenario would not pass for me.

Either relocate the point of entry or add a main disconnect on the exterior.

Hmmm... any relocation of the entrance is a PITA.

If I place the panel on the desired entry wall and skip the 11' run under the stairway, I'll have a 4"x16" beam to drill through for every branch circuit wire.

Is there a minimum height requirement for an outside disconnect?

 

[spudley]

Is this a subpanel fed from your house?

Yes but the house panel is 40' away and in a basement.

 

[acer66]

I was under NEC 2014 when I remodeled my house and detached garage.
Main panel which is a technically a sub panel
because of a disconnect at the meter
has an almost 30’ inside run before entering the panel.

My garage is fed, mhf in conduit, from the main panel and runs 45’ in the crawlspace before exiting the house.

The main panel was original on the other side of the wall of the meter
but I moved it into another room while leaving the meter box in place
and that was never brought up as an issue by the inspector.

 

[sberry]

Find the gas line. Dig.

 

[spudley]

Here are some NEC (2011 anyway) requirements. There doesn't seem to be a hard length requirement, only that "The disconnecting means shall be at a readily accessible location nearest the point of entrance of the conductors."

225.31 Disconnecting Means.
Means shall be provided for disconnecting all ungrounded conductors that supply or pass through the building or structure.

225.32 Location.
The disconnecting means shall be installed either inside or outside of the building or structure served or where the conductors pass through the building or structure. The disconnecting means shall be at a readily accessible location nearest the point of entrance of the conductors. For the purposes of this section, the requirements in 230.6 shall be utilized.

225.33 Maximum Number of Disconnects.
(A) General. The disconnecting means for each supply permitted by 225.30 shall consist of not more than six switches or six circuit breakers mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be no more than six disconnects per supply grouped in any one location.

Maybe I can convince the inspector the breaker panel location is the nearest "readily accessible location".
I'm putting a small restroom under the stairway so that's out, so the panel will be just outside this area which allows for proper access.
Hope he's in a good mood, which he usually is.
Thanks guys!

 

[spudley]

Find the gas line. Dig.

That may be plan B. I bought enough MHF to use this option if need be. But no digging until spring now.

 

[acer66]

Maybe I can convince the inspector the breaker panel location is the nearest "readily accessible location".
I'm putting a small restroom under the stairway so that's out, so the panel will be just outside this area which allows for proper access.
Hope he's in a good mood, which he usually is.
Thanks guys!

Yes, I would just talk to him too.
At the beginning it was a bit odd
but by the end I had a pretty good relationship with my inspector.

 

[spudley]

Yes, I would just talk to him too.
At the beginning it was a bit odd
but by the end I had a pretty good relationship with my inspector.

Last time my guy stopped by (unannounced), I couldn't get him to leave. He was lamenting some new jurisdictions on his plate where lots of work wasn't to code. He said he really hated telling folks to redo what they thought was working just fine, and he sounded like he meant it!

 

[sberry]

Is the ground froze there now? We can still dig here, last winter it never did freeze down.

 

[acer66]

Last time my guy stopped by (unannounced), I couldn't get him to leave. He was lamenting some new jurisdictions on his plate where lots of work wasn't to code. He said he really hated telling folks to redo what they thought was working just fine, and he sounded like he meant it!

Great, it really pays off to have a good relationship with the inspector.

We once had an inspector who was totally into Micheal Schumacher when he was still in the Formula 1 and because my boss was German he thought he must be into him as well.
Problem was my boss could not care less about F1 so every day the inspector was scheduled I briefed my boss in the morning about the latest in F1 so they could have a nice little chat.

 

[Norcal]

I need to look at the whole article it may only cover service entrance conductors where you do not want excessive lengths of conductors that have no overcurrent protection in a building.

 

[PCustoms]

I need to look at the whole article it may only cover service entrance conductors where you do not want excessive lengths of conductors that have no overcurrent protection in a building.

Is this a subpanel fed from your house?

Kind of what I was getting at. I had looked into this a while back, I am 90% sure it doesn't apply here as the OP has overcurrent protection on the feeder.

 

[pattenp]

Most places seem to only allow 5-6 feet of un-overcurrent protected service entry cable to be run within the structure. Two ways to usually overcome that is to add an OCPD outside or run the cable in RMC to the breaker panel. It really depends on you local inspector.

 

[wyliesdiesels]

Most places seem to only allow 5-6 feet of un-overcurrent protected service entry cable to be run within the structure. Two ways to usually overcome that is to add an OCPD outside or run the cable in RMC to the breaker panel. It really depends on you local inspector.

In comment #6 OP said this is a sub panel off his house service.

 

[75gmck25]

I think I need some clarification of how this will be connected. If he is adding a subpanel off the main panel in a house that is 40' away, then it is not service entrance, its a subpanel in a detached building.

The main panel would have a breaker for the subpanel (overcurrent protection), so you just need to make sure the subpanel wiring meets the other NEC requirements (dual rated MHF in conduit if its inside the dwelling, proper grounding, 4 wire cable, etc.). Or am I confused about the requirement?

Buce

 

[mm08822]

I need to look at the whole article it may only cover service entrance conductors where you do not want excessive lengths of conductors that have no overcurrent protection in a building.

NEC 225 Part II covers buildings or structures supplied by a feeder or branch ckt specifically.

As mentioned, 225.32 states "nearest the point of entrance of the conductors".

 

[mm08822]

I think I need some clarification of how this will be connected. If he is adding a subpanel off the main panel in a house that is 40' away, then it is not service entrance, its a subpanel in a detached building.

The main panel would have a breaker for the subpanel (overcurrent protection), so you just need to make sure the subpanel wiring meets the other NEC requirements (dual rated MHF in conduit if its inside the dwelling, proper grounding, 4 wire cable, etc.). Or am I confused about the requirement?

Buce

Need to meet NEC 225.32

 

[pattenp]

In comment #6 OP said this is a sub panel off his house service.

I was thinking entry of the main service conductors. I don't know how I went down that road with this being an OCD protected feeder.

 

[spudley]

Is the ground froze there now? We can still dig here, last winter it never did freeze down.

We had 4" of frost by late October! But since then it's been warmer and we've had a fair amount of snow cover so it might have thawed.

This garage is on a lake 200 miles from where I live so it's hit and miss when I get a chance to work on it.

I hung the panel and started running inside wire. I'll check if the inspector will allow the longer inside run and go from there. I can eliminate nearly all of the inside run by further trenching, just wanted to avoid the gas line and an LB on my neighbors side of the building. I'm more than a little OCD.

Sorry that I'm tardy with the reply but I have no internet and limited phone reception in the furthest reaches of the realm...intentionally as I just retired from a job where I spent my days in meetings, on the phone, or travelling.

But I just (unfortunately) returned from that blissful quiet solitude to civilization.

Thanks guys.

 

[larry4406]

Slight hi-jack of thread...(sorry)

I have a new construction detached single family home coming up. Client wants to install external 400A disconnect at the meter can then free wire SER inside the home to locate the panels in a central mechanical room about 30' way. Kosher or is conduit required?

 

[75gmck25]

A neighbor of mine converted from overhead to buried power lines and wanted to move the breaker box to the other side of the house (about 25'). They installed a disconnect at the front of the house where the new power line came up out of the ground and connected to the meter, and ran SER to the back wall of the house to connect the panel. AFAIK there was no requirement for conduit for the SER inside the house. This was Dominion power and Alexandria, VA city inspection. However, maybe 400 amp service would have additional requirements.

Bruce

 

[larry4406]

A neighbor of mine converted from overhead to buried power lines and wanted to move the breaker box to the other side of the house (about 25'). They installed a disconnect at the front of the house where the new power line came up out of the ground and connected to the meter, and ran SER to the back wall of the house to connect the panel. AFAIK there was no requirement for conduit for the SER inside the house. This was Dominion power and Alexandria, VA city inspection. However, maybe 400 amp service would have additional requirements.

Bruce

Thanks Bruce. Mine will be Dominion VA Power as well but Fairfax County. The electrician for the job says disconnect with free run SER is fine but I like to trust but verify.

 

[wyliesdiesels]

A neighbor of mine converted from overhead to buried power lines and wanted to move the breaker box to the other side of the house (about 25'). They installed a disconnect at the front of the house where the new power line came up out of the ground and connected to the meter, and ran SER to the back wall of the house to connect the panel. AFAIK there was no requirement for conduit for the SER inside the house. This was Dominion power and Alexandria, VA city inspection. However, maybe 400 amp service would have additional requirements.

Bruce

There shouldnt be a requirement for SER to be in conduit since it has an outer jacket.