3 conductors or 4?

200 Amps. service panel in detached garage feeding a 200 Amps. panel in house:
1- wouldn’t the panel in house considered a sub panel?
2-shouldn’t there be 4 conductors to the house panel from the service panel?

3 wire WAS permitted until the more recent code cycles IF their were no other conductors between the home and other building.

In the US, three wire feeds were allowed if there were not continuous metallic paths between the structures. The sub panel would then be wired with the grounding and grounded conductors bonded together.

It is not allowed anymore though.

House was built in 2011.

The panel in house should be sub panel and neutral should be isolated from ground, no?

It really depends on when you area adopted the code that changed it.

It think it was in 2008.

I suppose if you want to have a fun conversation you could call the AHJ. :wink:

To answer your question, yes

Yes three wires not allowed in Canada .
Steel pipe is approved as the grnd two hot and neutral
Only one ground in the system at the primary panel.

Sorry Marcel. I forgot you were in Canada. My bad.

Thanks for the prompt replies!

Below is what I put in the report:

**· Safety Issue Possible Major Concern: There is no ground wire included with the feeder wires that carry power from the main distribution panel in detached garage to the auxiliary panel in the house. This means that the auxiliary panel is not grounded back to the main panel. Without a ground wire between the auxiliary panel and the main panel, the auxiliary panel and the branch circuit wiring it contains will not be adequately grounded. You should engage a qualified licensed electrician to further evaluate this condition and provide repair recommendations. **

That panel looks like the neutral bar is isolated from the ground bar with no bonding between the two. Yes?

Correct the primary panel is the only place the neutral is connected to the grnd .
Sorry I should have explained that better …
I was just in and out of the house before .

The strap between the neutral and Ground bus is in the picture.

Look again.

Yes, there should be four conductors, however (as others have said), it may have been allowed at some point, but not like this.

Regardless of a three or four wire feed, there must be a bond between panels and the grounding electrode. The panel pictured does not appear to have any bond at the cabinet. So the egc’s within this panel (and the panel itself) are not “grounded” (earthed), unless of course, it’s fed with a metal conduit. It appears to be plastic.

With the disconnect in that panel, I would say it appears to be the service equipment. Was there a service disconnect elsewhere?

The EGC’s and neutrals are landed on separate buses in the subpanel at the house. What you cannot see from the photo is whether or not the neutral is bonded to the enclosure. Could the connection could be behind the cover protecting the main CB?

There was a disconnect at the service equipment, at the service equipment panel for the auxiliary panel and at the auxiliary panel.

Neutrals were not isolated from ground at the auxiliary panel, at least they do not appear to be…