Cliff Rohrabacher
05-09-2007, 9:17 AM
I just installed a Siemen's sub panel using a Siemen's main 100 amp box as the sub. It came with a 100 amp breaker in place and a little box of 8 or so 20 amp breakers - - -and - - - nothing by way of a ground bus bar.
It's my preference ( and I believe Code) to never bond the Sub-Panel's supply Ground to the Sub-Panel's supply Neutral when the Sub is inside the main building. Which means the ground is swinging in the breeze.
That is absolutely wrong~!!
The Siemens' box has a little tag in it that instructs you to BOND the Neutral to the Ground. However I rather suspect that this applies only if the box is being used as the Main Panel.
Attaching the Supply Ground wire it to the sub panel wall is silly, 'cause I gotta strip paint to get a ground connection to the steel from which the box is made. And that'll still leave me with the issue of where to connect the ground wires from the breakers.
The Option that appeals is to get a ground buss bar and ground to that. I simply don't see a better way to do this. The grounding wire passes right over head so I can run a heavy ground wire right to the main ground too.
Any ideas?
************Another issue. **************
I have an older sub in another part of the house which is fed by #4 copper with BX shielded cable. The BX shielding is the ground and it is really old and I don't trust the old BX connections so I ran a heavy copper from the ground buss (that box has one) to the heavy grounding wire that happens to pass right overhead.
I wonder if the code guy will look funny at that.
It's my preference ( and I believe Code) to never bond the Sub-Panel's supply Ground to the Sub-Panel's supply Neutral when the Sub is inside the main building. Which means the ground is swinging in the breeze.
That is absolutely wrong~!!
The Siemens' box has a little tag in it that instructs you to BOND the Neutral to the Ground. However I rather suspect that this applies only if the box is being used as the Main Panel.
Attaching the Supply Ground wire it to the sub panel wall is silly, 'cause I gotta strip paint to get a ground connection to the steel from which the box is made. And that'll still leave me with the issue of where to connect the ground wires from the breakers.
The Option that appeals is to get a ground buss bar and ground to that. I simply don't see a better way to do this. The grounding wire passes right over head so I can run a heavy ground wire right to the main ground too.
Any ideas?
************Another issue. **************
I have an older sub in another part of the house which is fed by #4 copper with BX shielded cable. The BX shielding is the ground and it is really old and I don't trust the old BX connections so I ran a heavy copper from the ground buss (that box has one) to the heavy grounding wire that happens to pass right overhead.
I wonder if the code guy will look funny at that.