Running through a panelboard

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steve66

steve66

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Illinois
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Engineer
Is there anything to prevent someone from running power from one panel through another panel, then to the load?

I don't think there is, but I thought I would run it by the collective wisdom here.

Our "New" local electrical inspector just vetoed it on one of my projects. I think I'm going to realize how well I had it since the previous inspector was very fair about going "by the book".
 
steve66 said:
Is there anything to prevent someone from running power from one panel through another panel, then to the load?

I don't think there is, but I thought I would run it by the collective wisdom here.

Our "New" local electrical inspector just vetoed it on one of my projects. I think I'm going to realize how well I had it since the previous inspector was very fair about going "by the book".
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What code is he citing?
 
Take a look at 312.8. This section permits a cabinet to be used for a raceway provided that adequate space is provided for this purpose.

The inspector might be trying to use this section and not reading it thoroughly.

Chris
 
I had a inspect get me for this a couple years ago. He said that it didn't have adequate space, that the panel would have a extra chase built in for that purpose.

I had two 200 amp panels 6" apart with a 2" nipple between the panels. I had contactors beside one panel being feed through from the other panel.

Besides the space issue, he also said that if you were to kill the main of that panel to change the guts out to say, then you would still have live circuits running through.

So now i make sure i plan it out were i don't need to run through. I have put a wire trough below or above the panels to run through. I have also arranged the contactors so that i could pipe/flex below the panels.

IMO a 200amp QO panel board has adequate space. I can see killing the main and still having live circuit passing through being a hazard.
 
Sierrasparky said:
What code is he citing?
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I haven't talked directly to the inpsector, I going by what the electrician said. Actually, the electricians were the first ones to say "you can't run through a panel to another panel." I'm not sure they believed me when I told them that wasn't actually a code section.

Steve
 
raider1 said:
Take a look at 312.8. This section permits a cabinet to be used for a raceway provided that adequate space is provided for this purpose.

The inspector might be trying to use this section and not reading it thoroughly.

Chris
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After reading the section, I have to admit I haven't seen the electrician pull the front cover off the existing panel. Since all the breakers on the existing panel is already full, the inspector may be rejecting it based on wireway fill.

Steve
 
brandonhd said:
I had a inspect get me for this a couple years ago. He said that it didn't have adequate space, that the panel would have a extra chase built in for that purpose.

I had two 200 amp panels 6" apart with a 2" nipple between the panels. I had contactors beside one panel being feed through from the other panel.

Besides the space issue, he also said that if you were to kill the main of that panel to change the guts out to say, then you would still have live circuits running through.

So now i make sure i plan it out were i don't need to run through. I have put a wire trough below or above the panels to run through. I have also arranged the contactors so that i could pipe/flex below the panels.

IMO a 200amp QO panel board has adequate space. I can see killing the main and still having live circuit passing through being a hazard.
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Welcome to the forum.:)

The cabinet does not need to have a specific "chase" built in it to comply with 312.8. Modern cabinets have more than adeaquate space to run extra wires thought the cabinet.

It would take a lot of wires to fill the spaces in a cabinet for a panelboard to over 40% fill.

Chris
 
raider1 said:
Welcome to the forum.:)

The cabinet does not need to have a specific "chase" built in it to comply with 312.8. Modern cabinets have more than adeaquate space to run extra wires thought the cabinet.

It would take a lot of wires to fill the spaces in a cabinet for a panelboard to over 40% fill.

Chris
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Thanks, glad i found this great forum.

How do you feel about having a live circuit running through the panel coming from another source?
 
brandonhd said:
Thanks, glad i found this great forum.

How do you feel about having a live circuit running through the panel coming from another source?
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How I feel about it has no bearing on whether or not it is code compliant.

The NEC does not prohibit a circuit from another panelboard from passing through the cabinet of another panelboard if their is adequate room provided and the requirements of 300.3(C)(1) are met if there are different voltages involved.

Chris
 
celtic said:
How else would you get your 120V recpt. ckt.s out to the areas with your 277v lighting?

;)
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I don't mix voltages like that in the same circuit even if labled and color coded. I just think it's an accident waiting to happen.
 
brandonhd said:
...he also said that if you were to kill the main of that panel to change the guts out...
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The mentality of your inspector gets people hurt. Throwing a breaker, even the "main", does not give carte blanche to blithely cut every wire in sight without regard to the wire's power source . There are many devices and appliances that are routinely installed in panels, such as trip coils, relays and branch circuit monitoring.

I had a disagreement with a project manager over the use of a panel as a raceway. He conceded that it is legal by code, but asked if I would not do it again on any of his projects.
 
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celtic said:
How else would you get your 120V recpt. ckt.s out to the areas with your 277v lighting?

;)

Sierrasparky said:
I don't mix voltages like that in the same circuit even if labled and color coded. I just think it's an accident waiting to happen.

mcclary's electrical said:
How could you?
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Let's assume it was a typo....conduit/raceway.


Mixing ckts of different potentials is not on my list of favorite things to do...HOWEVER....it IS legal and if no other reasonable opportunity was available, I would install mix voltages in the same raceway even passing through different "tubs".
 
You guys need to get out more, mixing voltages in raceways is fairly common and legal.:)

Then there are the times 480 volt breakers use 120 volts for control power, kind of necessary to bring both voltages into a panel cabinet.

Never assume shutting of a panel feeder kills all circuits in a cabinet.
 
iwire said:
You guys need to get out more, mixing voltages in raceways is fairly common and legal.:)

Then there are the times 480 volt breakers use 120 volts for control power, kind of necessary to bring both voltages into a panel cabinet.

Never assume shutting of a panel feeder kills all circuits in a cabinet.
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Yea I get that one but Celtic was reffering to 277v lighting and 120v recepts in a typical commercial environment. I would never do this because I think it is never necessary, practical and is a accident waiting to occur. In my beggining our 480v/277 cts were always in seperate conduits. except for control circuits. Just because you can does not mean you should. Is there a big savings doing so?
 
The funny thing was that in the case I was refering to, an existing panel was going to feed a new subpanel.

So the branch circuits were going to run through the existing panel to the new panel.

Shut off power to the existing panel, and that also kills the power to the subpanel.

So in this particular case, having a voltage present after shutting off the power wasn't even an issue.

Steve
 
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