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Kinger
11-23-2008, 08:37 PM
I installed a main lug panel in my attached garage this weekend.

The question I have is, it did not come with a grounding strip. I picked up an equipment grounding strip on a another trip to the store. It does not fit the mounting holes. Has anyone run into this before?

I have read through the numerous posts here and on other forums online. If I am understanding things correctly, I need to have a ground bar in the main lug, to maintain the grounding from the main panel.

I installed:
Square D Homeline, 100 Amp main lug
I used 8/3 wire (thought that is what the electrician recommended for 60 amps, but I think I might have shorted myself).

Thanks

sberry
11-23-2008, 08:55 PM
Technically you should have a 40A breaker in front of that wire, 6-3 w/g would have been far superior breakered at 50A. In the sub, you do not install the green bond screw that came with the panel in the neutral bar but all the grounds are connected together and bonded to the box via the bar attached with threaded screws or bolted to box. (no self drillers allowed to connect grounds)

Kinger
11-23-2008, 09:17 PM
Technically you should have a 40A breaker in front of that wire, 6-3 w/g would have been far superior breakered at 50A. In the sub, you do not install the green bond screw that came with the panel in the neutral bar but all the grounds are connected together and bonded to the box via the bar attached with threaded screws or bolted to box. (no self drillers allowed to connect grounds)

Thanks for the reply.

I did not install the bonding screw. The bonding bar for the grounds is what doesn't line up with the holes to be threaded into the box. I will have to try and bolt it or see if they sell a longer one that would line up with the holes.

I may bite the bullet and repull the wire. Just don't tell the wife!

LoneGunman
11-23-2008, 10:44 PM
Drill a hole in the panel and thread the hole for your mounting screw, as sberry stated, self tappers are not allowed.

What size breaker is feeding the 8/3 from the house?

*nevermind, reread your post. You need to either repull it with the correct wire or drop the breaker size. Why not go for 100 amp, long run?

Terry Kennedy
11-23-2008, 11:37 PM
The question I have is, it did not come with a grounding strip. I picked up an equipment grounding strip on a another trip to the store. It does not fit the mounting holes. Has anyone run into this before?

Square D Homeline, 100 Amp main lug

I'm not sure about the Homeline series, but the QO series panels have a huge number of grounding strips, not all of which work in all panels.

Ok, after looking, here (http://ecatalog.squared.com/catalog/174/html/sections/01/17401014.html) is the Homeline list. Pick the correct grounding strip for your panel. Probably a PK7GTA (http://ecatalog.squared.com/fulldetail.cfm?partnumber=PK7GTA) which has only 7 positions, so you may need more than one.

Kinger
11-23-2008, 11:57 PM
What size breaker is feeding the 8/3 from the house?

*nevermind, reread your post. You need to either repull it with the correct wire or drop the breaker size. Why not go for 100 amp, long run?

In reality I don't think I would ever use the load, plus I was trying to save some money. (That option is out the window if I repull wire)

I mostly do light car and motorcycle repair/maintenance. I don't foresee a lift in the near future, probably never at this house. I really only think I might get a 220v compressor in the future. I know things change.........


I'm not sure about the Homeline series, but the QO series panels have a huge number of grounding strips, not all of which work in all panels.

Ok, after looking, here (http://ecatalog.squared.com/catalog/174/html/sections/01/17401014.html) is the Homeline list. Pick the correct grounding strip for your panel. Probably a PK7GTA (http://ecatalog.squared.com/fulldetail.cfm?partnumber=PK7GTA) which has only 7 positions, so you may need more than one.

Thanks. I bought the PK15GTA. I will pick up two 7GTA's next time I go to the store.

Thanks

Kinger
11-23-2008, 11:59 PM
Second question:

Is it worth setting up a main breaker in the sub panel?

Terry Kennedy
11-24-2008, 01:00 AM
Second question:

Is it worth setting up a main breaker in the sub panel?
It is a handy way to shut everything off at once. I would do it whenever the subpanel is not adjacent to the panel that feeds it.

However, main breakers can get *very* expensive. On the QO 40-position panel, the panel (including 200A main breaker) was $192 at Home Depot, but the best price I could find for a 100A main breaker alone was $194 at Grainger.

JohnK007
11-24-2008, 08:59 AM
I have 8/3 feeding a four position sub panel in my detached garage. It's connected to a 40 amp breaker at the main. Largest circuit in the garage is a 30A 220 that fed my welder, but now feeds a 5000W electric heater. The other two manage the lights and wall receptacles.
My point is I think 40A is the best you're going to get out of 8/3. But don't despair. If you're not pulling a high, sustained load, 40 amps is a lot of juice. Why not give it a try for a while and see if you trip the breaker a lot. You can always re-pull later.

prestonjrf
11-24-2008, 09:35 AM
Will removing one of the screws in another space line it up? If so just put the lug screw in the leftover spot.

sberry
11-24-2008, 11:10 AM
A panel in an attached building does not require a main breaker.

Aceman
11-24-2008, 08:19 PM
If you're not pulling a high, sustained load, 40 amps is a lot of juice. Why not give it a try for a while and see if you trip the breaker a lot. You can always re-pull later.

I agree......