Service entrance into main panel

WillK · 06-02-2011, 10:47 PM

Okay, since I'm not doing this part of the work until tommorrow I'll solicit advice in case I'm making it harder for myself than I need to.

Second rough inspection, the inspector objected to the routing of the service entrance cable on my panel and said it should go straight into the panel.

In the photo below I labelled what I planned to do as "knockout 2" which will require moving the panel up and to the left, removing the cabinet on the adjacent wall, re-running the conduit for the garage subpanel feeder at the bottom and splicing the feeder cables to add length.

Knockout 2 is a knockout in the back of the panel.

Could I make it easier by using "Knockout 1" as shown in the photo which is a side entrance? Quite frankly in my opinion, it'd be a little difficult to make the turn on the nearest hot conductor. I'd still have enough cable to do knockout 2 if I had to... But if I tried doing this, I'd really appreciate a code reference so I can speak intelligently to the inspector about why I didn't do what he said.

Knockout 1 would keep me from substantial panel remounting and cable restapling work plus the garage feeder could stay where it is.

I'm thinking knockout 1 should be less than 36" and somehow that is something that might be in code as far as maximum length to not require seperate disconnect... I was thinking that the length I had as-is was probably under the requirement since it couldn't possibly be more than you'd get if the panel was in a basement.

Jim Port · 06-02-2011, 10:55 PM

I don't see that using either KO1 or how you have it now is meeting the requirement for the unfused cable to be " as short as practical". IMO using KO2 would meet. IMO I would let you leave the panel where it is and just use KO2. I would not beat you up over the couple of inches. I would have mounted the panel 180 degrees so the main was at the bottom. I remember you said the feeder got too short, but it could be spliced in the panel.

jbfan · 06-02-2011, 11:07 PM

I would remove the left hand 2x, holesaw your own knock out into the side, and install the cable there.

kbsparky · 06-02-2011, 11:12 PM

TURN that panel over, so the main is at the bottom. THEN use the back knockout that will be in the same position as #2 on your pic.

WillK · 06-02-2011, 11:23 PM

Holesawing is a bit unpleasant, the whole side has knockouts that make for difficulty with the pilot hole and the saw grabbing...

If I used KO2 which is on the back, what is required with the openning? Can something other than a clamp be used? I have a clamp, but I'm concerned whether I'd be able to make the turn before hitting the cover without violating table 312.6(a) as referenced by 314.28, I'd need 4" to make the turn but I only have 3-3/4"

WillK · 06-02-2011, 11:29 PM

Quote:

Originally Posted by kbsparky

TURN that panel over, so the main is at the bottom. THEN use the back knockout that will be in the same position as #2 on your pic.

If I turn it over, #1 is at the bottom and a side entrance becomes easier.. How about that one then? I'm kind of thinking a back entrance is difficult to do without a straight shot into the panel.

Kind of.. I mean, there's a KO on the side at the top on the left and the right. There are side KO's at the bottom but they only go up to 1-1/4" and that's not enough to get 4/0 through... And it is enough to make holesawing not work so well.

Tigerloose · 06-02-2011, 11:33 PM

Is there a main disconnect at the meter? There is no equipment ground or neutral run with the feeder at the bottom? How about an equipment ground from the meter cabinet?

WillK · 06-02-2011, 11:36 PM

Main breaker on the panel is to be the disconnect. My POCO does not allow any ground conductors to enter the meter socket. (for anybody else, consult your POCO as your answer may vary)

The feeder at the bottom goes through the wall with rigid metal conduit which acts as the ground conductor. There is a clamp below the LB fitting outside through which a #4 copper wire passes on its way to the first and second ground rods.

frenchelectrican · 06-03-2011, 12:59 AM

If I were ya I will just flip the box around and run the SE cable from below and termated it and you can actually move the load centré over a bit so you can have a direct way to the meter socket and be aware that when you try to bend the SE cable they don't like sharp bend so that why I rather do in diffrent way.

I will have no issue makeing a new KO opening with holesaw or stepper bit one of the two will work.

How many green sticker you did have on the cover I did spotted.

Merci,
Marc

WillK · 06-03-2011, 02:20 AM

8 stickers so far, lessee if I can go by memory..

Mechanical - new gas pipes
plumbing - dishwasher I think
Electrical rough on kitchen
Electrical rough on upstairs bedroom
Building - roofing
Building - first 2 footings
Building - first 2 footings for center beam
Electrical - trench only

Thats all just since I bought the house.

Jim Port · 06-03-2011, 07:03 AM

Hard to tell from the pic, but that cabinet looks like it might be in the workspace for the panel. Is it more than 3' away from the panel face?

In my earlier post I thoght KO2 was in the side, not the back. Is there a large 2" KO in the side?

WillK · 06-03-2011, 07:10 AM

Knockout 1 is up to 2".

A side knockout exists on the side near knockout 2, but the max. size is 1-1/4" which isn't large enough.

The cabinet is too close if the panel moved. It would have to go.

WillK · 06-03-2011, 07:56 AM

So weighing my options:

Not under consideration:
1) as-is. Already rejected.
2) knockout 1 side entrance. Still does not meet requirements.
3) knockout 2 rear entrance without move. Not enough space to make bends

Viable options:
1) Flip the panel for a side entrance near the SE cable wall penetration
pro: panel location not changed, garage feeder conduit unchanged
con: all panel connections need to be disassembled, the panel still needs to be removed, questionable if same breaker KO's will still work, closest breaker for garage feeder might not reach so a splice might still be needed. Different than what the inspector requested.

2) Move the panel up and to the left, use knockout 2
pro: most panel connections can stay together, no change to breaker locations, it is what the inspector asked for
con: garage feeder needs to be spliced, cabinet needs to be removed, need to assemble new garage feeder conduit run.

I really appreciate all the feedback and options, but it sounds like the original plan is still the best choice.

The cabinet is not a very big deal, it's mostly tools and hardware the wife wants out of the laundry room anyway, plus the cabinet door is over the cat box and it's a good place to hit one's head while cleaning the cat box. It's a 50's metal kitchen cabinet, so it would go with the base cabinets I have in the garage which I'll be using as a workbench most likely... And it would probably be thematicly consistent with the cars I'll be working on and keeping in the garage anyway.