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bauer09
Jan 12, 2011, 08:47 PM
I've searched and read a lot on this site about folks who have been relocating electrical panels, so I hate to throw a question out there that's been answered, but as usual there are always different specifics.

I am renovating a duplex (originally a 90 year old single family home that was converted years ago). I have no faith in what the prior owners did with the electrical - it is a mix of knob and tube and retro-fit... Some of the knob and tube had insulation blown in/around it... So I just don't trust it and would feel much better just disconnecting it and running all new while we are renovating.

There are two meters for the house, but both breaker boxes are in the basement. They are governed by 60amp breakers, although the service outside is upgraded. I would like to move the 2nd floor apartment breaker box to the 2nd floor - since those tenants do not have access to the basement, I would like them to be able to get to the breaker box.

Do my two options essentially come down to:

1. Add a main disconnect at the meter and running 4 wires to the 2nd floor breaker box

2. Use the old breaker box and run a sub panel off it to the 2nd floor (similar option to #1, but may allow me to keep some circuits in that original box - such as power for the heater which is in the basement)

Am I missing something here? I figured running straight from the meter to a breaker box on the 2nd floor has too many obstacles associated with it since it would be such a long stretch of un-fused wire...

Any thoughts about what would be easiest would be greatly appreciated. And thank you tkrussel if you catch this, I have enjoyed reading your detailed explanations.

And yes any work I perform will be inspected...

tkrussell
Jan 13, 2011, 04:56 AM
I would do option #1, add a main breaker at the meter location, run a 4 wire feeder to the second floorapt, and install the panel there.

Tenants must always have access to their panelboard.

Leaving the panel in the basement and running a feeder to the apt off that would still not allow access to the panel.

As long as you install a Main for the second floor apt at the meter, the feeder will be protected. This must be done, as unprotected feeder is not allowed to run much more than 10 feet inside a building. That is an unwritten rule, as the Code states "immediately".

bauer09
Jan 13, 2011, 05:29 AM
Thanks TK -- that helps. This place really is a mess, I don't know how it has been functional for the past 90 years.

Do you think I should install the main disconnect where the old service panel was -- or actually put it outside? It's a small 3-bedroom apartment with gas heat, dryer, stove so I am confident a 100amp main service will suffice, although I'm going to run the load calc's on all the circuits I'm planning to add to make sure...

Also, the main panel breaker is 60amp... I am assuming they did this because the majority of the house is still knob and tube and they didn't want to over-fuse (if that's a term) that wiring... the meter and service drop are new, so provided I check the size of the incoming wire, I should be able to amp the service at 100, correct?

And lastly, is it true I cannot locate a panel on a landing of a stairwell? I have seen stairs are prohibited locations for panels...


Thanks again

tkrussell
Jan 13, 2011, 05:38 AM
It would be better to have the Main at the meter.

Yes, I meant to mention panels cannot be in stairways, or clothes closets.

Size of Main has nothing to do with the type of wiring method in a building, simply seized by doing service rating calcualtions, which should be done for both apartments and any common area loads.

bauer09
Jan 13, 2011, 08:42 AM
Gotcha - I guess then they just never changed the main breaker from 60amp.

Cheaper/Easier to run the cable from the disconnect inside at up rather than up the side of the building in conduit?

And would it be necessary (or just a good idea) to add a "main" breaker in the distribution panel that will be added on the 2nd floor?

tkrussell
Jan 14, 2011, 03:40 AM
Not necessary, but not a bad idea to have a Main CB in a subpanel. Depending on the path the cable needs to take inside, it may be easier to install a conduit on the exterior to get to the new panel location.

Now here is where the Code can be your friend. If you run a new line on the exterior of the building from the meter to the new panel, and the panel can be on the interior of the exterior wall, and the feeder will connect to the panel "immediately", then a Main Breaker at the meter will not be needed.

bauer09
Jan 14, 2011, 09:15 AM
Thanks again for your expertise tk --

So the requirement of "immediately" is just once it enters the building... how could I address the issue of grounding then from the 2nd floor? Separate grounding wire back down from the new panel to the original grounding position?

tkrussell
Jan 14, 2011, 09:25 AM
You know something, forget this last idea I proposed.

There is another requirement that all service disconnects be grouped at one location I forgot about.

You would still need a Main at the meter.

bauer09
Jan 14, 2011, 11:02 AM
Hmm... all service disconnects for a single building? It doesn't matter that the 1st floor has a separate meter?

If so, can the service disconnect be as simple as a 100amp breaker in an outdoor box?


I know this will all come down to the inspectors decision, but the faster I can get it right, the less time I need to wait until its done...

tkrussell
Jan 14, 2011, 11:54 AM
Yes, all service disconnects, for each apartment, must be grouped at one location.

bauer09
Mar 23, 2011, 03:47 PM
I'm almost all worked up and ready for rough inspection, but I have a quick clarification about my feeder wire before I go purchase it, so I dug up my old thread as opposed to starting a new one.

I am running a 4-wire cable from a main disconnect outside at the meter, through the basement, up inside to the panelboard in the 2nd floor apartment. My first question involves the wire size --- I believe I am under the provisions of 310.15(B)(7) (2011) regarding service feeder because the wire will be carrying 100% of the dwelling's load. According to that table, #2 aluminum wire should suffice for my 100amp breaker -- so I was planning on using 2-2-2-4 aluminum service cable as it is readily available at the big box stores.

Is this cable acceptable to run unprotected through the basement & walls? Would I transition to conduit through the exterior wall and up to the main disconnect by the meter? Could I also use this same wire size for the short connection between the meter and the main disconnect?

Thanks for the help -- as stated, all work will be inspected