SER to subpanel


Old 01-31-05, 07:10 AM
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SER to subpanel

I am using 2 awg Al SER from the mian to the service panel from a 100 amp breaker. I need to add some lugs to the ground/neutral in the main (cause those are sime big cables, but there is limited room). I have a seperate (small) bus in the panel with nothing on it.
By the fact that the panel is bonded to the neutral and the extra bus is attached to the panel (one screw hold it on), is there a need to run a connecting wire from this small bus to the main nuetral/ground bus (that everything else is run to)? Is the small bus considered bonded by the fact that it touches the case, or should there be a more conductive means of connection, since this will be for a subpanel that could draw up to 50 amps at a time (in the future, as this will have the only available spaces). Thanks!
Old 01-31-05, 07:30 AM
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Is the subpanel in the same building as the main panel? Does the cable have three wires or four?
Old 02-01-05, 08:38 AM
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sub and main

The subpanel is next to the main panel and hte 2 awg cable is a 4 wire SER with a solid black and black w/ red stripe, black w/white strip, and bare Al wire.
The 2awg is wired to the main lugs in the subpanel, blk w/white stripe is to nuetral bus (isolated from EGC) the other 2 black to the 2 poles (current) and the bare AL is to the grounding bus.
In the main panel I have a 100amp breaker, that will recieve the blk & blk w/red stripe. the other 2, the grounded (white) and the grounding (bare) I need to attach to the nuetral bus in teh main panel.

The problem is this:
The 2 awg wire is to thick to fit to the bus, so I need to add a lug to the bus. I have a seperate bus bar that is in the main panel, that has a lug attached to it, and I added another lug.

Do I need to have some additional large gauge connection from the bus in the main panel (where all the other nuetral and ground wires run to) to the small bus that is attached inside the main panel (but more towards the outer edge of the box) where I want to attach the nuetral and ground from the feeder cable.

i.e. because the main panel is bonded, does that create a good enough connection for the additional bus bar, or does the new smaller bus (w/ feeder attached) need to be connected to the other nuetral bus bar by a wire?


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