Replies

1. 
   cap | Jan 29, 2008 08:00am | #1

   Ted,

   Good choice on the QO panel.  The QO breakers have a great response, trip real fast compared to most other brands.  And it's real easy to see a tripped QO--you can't miss the red indicator.

   Anyway, mounting the panel--in a 24" stud bay, I run two  pieces of 1x4 or 2x4 stock across the bay (depending on the depth of the studs), and toe screw 'em into the studs.  Line the blocking up with the mounting holes in the back of the panel.  Use more blocking and shims as necessary to set the depth of the panel, so that the back of the panel rests on the two cross pieces and stands just a hair short of 1/2" proud of the wall finished surface, or whatever thickness of 'rock or plaster or paneling you've got.  I level it up, and use four or five #10 or #12 by 3/4" or longer hex head screws to attach the panel to the blocking.  Is that clear as mud?

   This approach gives me a few inches of space on each side of the panel that's free and clear, so I can run the romex into the knockouts in the sides of the panel.  If you're bringing a bunch of home runs into the panel, it's nice to be able to use the KOs on the sides.

   Hint--it's a lot easier to remove the KOs before then panel is mounted.

   In a 16" OC stud situation, I screw one side of the panel to one of the studs, and at the other side, place a diagonal block between the back of the panel and the rock on the other side.  Tow-screw the diagonal block into the studs, and put a couple of screws through the panel back into the diagonal block.  With this approach, I've got one side of the panel (and the top and bottom) free to bring cables in.  If you're not intending to use many of the 30 spaces, this is a quick and efficient approach.  I use one of the big C-clamp style visegrip pliers to clamp the panel to the stud while I'm mounting it, it makes for a fast install.

   In either instance, using 3M stackers (multi-cable clips) is a big help in fastening the cables within 12 inches of where they enter the box, as required by Code.

   Cliff

1. 
   webted | Jan 30, 2008 01:21am | #2

   Hi Cliff:Thanks a lot for the note. I've greatly enjoyed your articles in the past - for a guy like me that learned basic house wiring years ago, you've really helped me keep my DIY work at or above code. FYI, I'll have a licensed electrician help me complete the wiring at the main and sub-junctions. I've only wired in a few sub-panels, but I think the QO is just a lot easier for a DIY-guy to install. Being able to find the tripped breaker is a big bonus - I think shop equipment tends to trip breakers a lot more than household loads.Because the load center is going into an exterior wall, I was hoping to save that 3/4" behind it for insulation, but I think I should just probably go with the back blocking and worry about other things. My knuckles want to thank you in advance for the tip on getting the KO's off the side before mounting. I figured I'd put 2X4 blocking above the panel to provide a wire support (ala your "Subpanels" article a few years ago) for the lines coming in from above. I only discovered the cable stackers a year ago, and they've definitely made my work a lot neater.Thanks again,-t

1. 
   rfarnham | Feb 01, 2008 10:50am | #3

   Not much to add to Cliff's excellent description. That's pretty much how I did mine. It's really nice to have access to both sides, the top and the bottom, so I can bring the wires in where I want to. If you want insulation, you could still put in a piece of 1/2" or 3/4 XPS foam board behind the panel in the areas that don't have the 1x bracing. Better than nothing.One word of caution: Be careful with those stackers. I was sold on them the first time I used them as well (wiring a friend's place), and started using them when I wired my house. After we had a few of them in we had to pull a wire to re-route something and realized that the stacker had damaged the insulation on the wire. We started checking the rest and found the problem to be fairly common. Not everywhere, but enough that it made me nervous. I pulled all of them out and went back to those white plastic staples with the nail on each side.It was probably just a compatibility thing--that brand of stacker and that brand of wire, because I doubt this is happening everywhere or we'd see more electrical fires.-Rich

2. 
   Luka | Feb 01, 2008 02:01pm | #4

   Cliff,You know, in addition to what you already pointed out, what I really like about the QO's is the way they snap positively on the "back" end of the breaker, when installed.

   
   Yeah, it may be cold, but at least it's a wet cold !