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Question:

Here is a new sub panel adjacent to a Sylvania service panel. The electrician took all the branch circuits and moved them into the sub panel, but not the neutral or equipment grounds. There is no equipment ground feeder, the neutral appears undersized and a a new gec that has been installed in the ground below the picture. PVC conduit is between the two panels. I have never seen this before or if so, the sub is installed with a a four wire feed, separate gec, etc.... What do you know?

 panel

Response:

Don't you just hate it when someone does something nonstandard.

Neutral and ground are still separated at the sub panel.

Neutral and ground are bonded at the service equipment.

Sub panel gounding conductors are connected back to the service equipment.

 

As near as I can figure, it is ok. However, let's see who else chimes in.

 

Response:

All understood. The two equipment grounding conductors visible at the sub panel are for separate branch circuits that are hard to see, but go two the right conduit. All understood. The two equipment grounding conductors visible at the sub panel are for separate branch circuits that are hard to see, but go two the right conduit. Size of the neutral feed? Are there any exceptions when the panels are this close.

 

Response:

 

That sub panel is not grounded back to the main panel because the PVC conduit between the panels breaks the bond. It needs to have a ground wire from the neutral buss bar in the service panel to the ground buss in the sub panel.

 

That neutral wire from the service panel to the sub panel is undersized and needs to be the same size as the two hot conductors.

 

Thats what I see.

 

Response:

Hadn't even thought about the neutral conductors. Todd is right. I disagree about the bonding though. The grounding conductor should provide the bond.

 

Response:

The GEC has been moved thus resulting in a splice in sub panel and appears to change in gauge size - not allowed per NEC 250.64c

 

Response:

The main service breakers are in the on position, I think it may be an optical illusion or my uncanny photographic skills. There is a separate gec in the service panel that goes to a rod into the foundation (home is circa 1969).

 

Response:

The main is not off, it is just orientated differently on the buss bar from the others. I still don't see where the ground in the sub panel is being fed back into the main panel.

 

Response:

The ground at the sub is not fed back to the service panel, I think the electrician thought the new gec would suffice.

 

Response:

The neutral wire needs to be the same size as the phase conductors (feeds to the sub panel) in order to carry an unbalanced load that may occur in the panel. If for some reason only one phase of the service was being used in the sub panel then the neutral wire needs to be able to carry neutral currents back to the service panel. If I remember correctly the rating for neutral wire ineeds to be 70% the size of the hots but most just size it the same size to avoid any problem.

It would the be the same premise as having 2 "hot" wires with a shared neutral on the same phase needing to have a neutral conductor double the size of the two breakers on the "hots".

This is why dishwasher / disposal circuits sharing a neutral need to be on different phases in the panel in order for the neutral to use the same size conductor as the hots.

If I am seeing this correct the main breaker is the black handled breaker on the left side of the panel. The breaker is being back fed from the top side of the panel near the meter.? NO?

Shouldn't the GEC be connected back to the "main" service panel and then go to a ground rod of ufer ground?

Maybe the picture does not show it , but the larger ground wire in the sub panel does not look to go back to the main panel.

 

Response:

- Sylvania Panel = Zinsco = Obsolete, Unsafe Junk

- Neutral to Sub Undersized

- Sub panel has breakers installed where the corresponding neutrals are terminated at the main panel

- Main Breaker is Installed upside down - so off is down, which is improper

- Main Breaker is back-fed and should be secured in place

- Main panel is being used as a raceway and is probably not listed as such

- Sub Panel appears directly grounded - improper, panel ground should terminate at main panel.