Accptable use for an old electrical panel?

[tonype]

I am an engineer and building inspector. Saw a home yesterday where a the electrical service was upgraded about 20 years ago. The new panel was placed in the garage and one large conduit was run from the garage (and the breakers in the new panel), to the old panel, in the basement, for reconnection into the system. In essence, the old panel was converted to one large junction box. A lipped (top and bottom only) sheetmetal piece was fitted over the panel (the original cover was removed). Is this a legit re-use of the old panel?

 

[roger]

Re: Accptable use for an old electrical panel?

This is not an uncommon way to do this.

My concern would be in the derating of the conductors in the conduit, not the old can being used for a junction box.

Of course some listing thumper may scream foul.

Roger

 

[frenchelectrican]

Re: Accptable use for an old electrical panel?

myself i did see few of them do that way. and in my option i am not too keen with this due the numbers of conducters and derating factors.

the worst part i already see ( of course i did swear ) is put new box right over the old one. i end up have a service call with it and it was a disaster zone there. i told my client that it need serious upgrading and change set up to meet the codes. [ i did not bother count how many volitatons was there the list was too long anyway.]

merci, Marc

 

[drtymex]

Re: Accptable use for an old electrical panel?

Well it's typical to see old panels become junction boxes in themselves and I have worked and converted a few old panels into junctions.

Well my AHJ,considers this acceptable and as long it has the cubic inch capacity for all the circuits and the original dead front is in good
condition,IJMO AND THE AHJ,it's considered legal and safe.There's no busbar to worry about,so panel blanks are not needed.

 

[hurk27]

Re: Accptable use for an old electrical panel?

While I have seen and done this. I guess the proper way would be to replace the old panel with a sub-panel and feed it off the new service. with that being said try to get a homeowner to go for the cost of this upgrade is a whole another story.
I just blank off the old openings and use it as a juntion box but I do leave it accesable. the one thing I asked in the old forum was is it premissable to extend the neutral bar and ground bar to this made JB to lower the amount of wire ran to the new service. but I don't think I got a anwser that said the NEC does not permit it. But I haven't done one in a while so I guess I'm still searching on that one.

 

[hurk27]

Re: Accptable use for an old electrical panel?

There's no busbar to worry about,so panel blanks are not needed.

???
I don,t belive you said that.
All openings have to allways be effictively closed whether there is buss bars or not as this is required on any electrical box. there is more to it that just being a shock hazard. Like arc-flash which could ingite the wood structure.

 

[hurk27]

Re: Accptable use for an old electrical panel?

take a look at 110.12 (A)

 

[electricman2]

Re: Accptable use for an old electrical panel?

What I have done is bolt or tack weld the cover closed and install a label "Junction Box Only"

 

[hurk27]

Re: Accptable use for an old electrical panel?

Bolt, screw? Yes tac-weld? No, as to being accesable not readly.
With splices in a JB it has to be accesable not readly. One word of caution since this is now a juntion box the cover now has to be bonded! This means that the factory sheat metal screws will no longer be allowed for this purpose as it has to be machine thread. if the factory screws are then every thing is fine but if not just install a bond between the cover and box.

 

[don_resqcapt19]

Re: Accptable use for an old electrical panel?

hurk,

This means that the factory sheat metal screws will no longer be allowed for this purpose as it has to be machine thread.

The factory screws are suitable for bonding the cover of an active panel, but not for a junction box cover?
Don

 

[hurk27]

Re: Accptable use for an old electrical panel?

Wasn't this talked about a few months ago that sheet metal type threaded screws are not acceptable for bonding. and a few years back many panel manufactures used sheat metal type screws to secure the panel cover. now they use only mechine threaded screws but since this would be concidered new work wouldn't the screws have to be brought up to todays code? Or at least bonded around them? Since this panel now serves a new purpose it's new?

[ November 13, 2003, 12:51 AM: Message edited by: hurk27 ]

 

[big jim]

Re: Accptable use for an old electrical panel?

I think there is a little bit of confusion about covers here. Some older panels did not have a door over the breaker area. Most new ones do. If you convert a doorless one to a J box, you certainly need to fill the holes in an acceptable manner. If it has a door, bolt, screw, or even weld it closed. Box is still accesable by removing the whole thing. I personally quit using sheet metal screws a long, long time ago after I drove a too long #10 into a too close 50 amp conductor. I automatically replace them with TCMS if I encounter them.

 

[tonype]

Re: Accptable use for an old electrical panel?

Just want to thank everyone for their insights - it helped alot.

 

[electricman2]

Re: Accptable use for an old electrical panel?

Quote by hurk27

Bolt, screw? Yes tac-weld? No, as to being accesable not readly

I only tack weld the hinged cover closed. The main cover is attached to the box with machine screws. I probably should have worded this different.