Weird wiring?


At last I got around to replacing the panel in the basement. Although the old one (Cutler-Hammer CH about 30 years old) still had one breaker space available, there was just no room to work in it and I needed still more spaces. Moreover, many of the holes in the bus bar had two or more wires, which I understand is not good.
This panel had only branch-circuit breakers, the "Main Switch" (tied 100A breakers) being in a panel in the garage (back-to-back with the meter), with that panel containing just one other breaker feeding the garage lights and outlets.
The first thing I noticed was that when I switched off that "Main Switch" in the garage, the garage circuits were still live; IOW, the breaker for the garage circuits were connected directly to the meter. So the "Main Switch" is not really a *Main* switch.
When I started ripping out the wires (previously labeled) from the panel in the basement, I discovered things I had not noticed before because it was just too crowded to see or because I had never checked:
(a) The box bonding screw was not screwed down, so was the box even grounded properly?
(b) The ground conductor from the panel in the garage was not connected to anything: it was just folded back on itself and stuffed into a corner, hidden by branch-circuit wiring. (The branch circuits nevertheless had grounds, because their neutrals and their grounds were both connected to the one bus bar that was connected to the neutral conductor from the panel in the garage.)
Was this kosher at the time it was done (30+ years ago)? My understanding is that now the "Main Switch" in the garage would be considered the "Service Disconnect", the main breaker in the new panel I have installed would be the "Main", and there should be separate ground and neutral buses in the panel in the basement (now technically a sub-panel). Have I got this werong?
The new panel (32-space 200A CH) has separate neutral and ground buses. I connected the neutral from the panel in the garage to the neutral bus and the ground to the ground bus, but did not connect them together in this panel. Is this correct?
Perce
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The panel in your garage is for "main" breakers only, and it can have up to six. You have two, one for the sub panel and one for the garage. The main breaker for the basement sub panel should be sized to the conductors feeding the panel, and if it is in the same building, a second disconnect is not required at the sub panel. The bonding jumper that was not connected on the old panel should NOT be connected on the new panel either. The neutral and ground busses should be separate and fed from individual conductors

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Interspersed responses follow.
On 11/14/06 07:05 am RBM wrote:

So this does not count as the "Service Disconnect"?

But the conductors feeding the sub panel are already protected by the 100A breakers in the panel in the garage. If the total load exceeds 100A, the breakers in the garage should trip.

Not having a disconnect at the sub panel is the equivalent of not having a main breaker for that sub panel, isn't it? The old sub panel did not have a main breaker.

There was a separate very small bus (Ground?) in the old panel, but there were no connections to it and it did not seem to be possible to isolate it from the other bus (to which both grounds and neutrals were connected -- and this was the bus with the loose box bonding screw).

And that is what I have now.
Perce

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In your case, you have two service disconnects, you are allowed up to six
You've already got the main feeder protected by the 100 amp breaker and don't need another main breaker in or at the sub panel The Neutral buss should be insulated on plastic blocks and the ground buss should be in contact with or bonded to the metal of the panel

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