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I'm in BC, Canada. I recently moved into a place that has a subpanel for a suite. The subpanel is connected to a 60A breaker in the main service panel. There are 4 wires running in from the main panel.

subpanel

My question is: The ground and neutral from the main panel are both connected to the bus that's being used for neutrals; is this incorrect in a subpanel?

The branch circuit grounds appear to all be connected to small bars at the back/side of the panel. I also don't understand how those bars are grounded but that's probably just my lack of knowledge.

I've posted some additional pictures here: https://imgur.com/a/FC3poMj.

(I've read of the poor reputation of Federal Pioneer Stab-lok so I plan to get this replaced anyway. I'm mostly just wondering if this is very wrong, or just "not great".)

  • Are all those unconnected red, black and white wires down the left side new runs that just haven't been connected yet, or were they in the panel when you opened it up? If they're not in use, they should be wire-capped, just to be sure. – FreeMan Jun 22 at 16:25
  • I haven't done anything other than take the cover off to see what was going on (the breakers weren't labeled at all). Thanks for the note. – Scott Jun 22 at 16:29
  • Ahhh... mystery breaker. Almost as tasty as mystery meat as the school cafeteria! Have fun with that! – FreeMan Jun 22 at 16:44
  • Not sure about the Canadian Elec. Code, but here in the US, they must be separated in sub-panels. Also, Federal Pioneer is not the same as Federal Pacific. The designs were originally the same, but they were always made in different factories and Federal Pioneer (the Canadian version) never lost their listing by faking their test documentation like Federal Pacific did. For a while, Federal Pioneer breakers were actually a viable alternative to FPE here in the US, until the people who bought the rights to the old FPE line here sued Federal Pioneer to stop them from selling here. – JRaef Jun 22 at 18:44
  • Ah, it is a different "Federal" too I guess. The inspectapedia site that comes up in many searches implies a relationship between the Canadian and US, but it wasn't overly clear to me what that relationship was or how much to worry about it. – Scott Jun 22 at 19:24
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It is wrong. The neutral and ground (from the supply feed) are connected and that's wrong. But what's worse is it doesn't appear to be bonded to the panel. That means the grounds have no path back to the main panel. You need to move the ground from the feed (the twisted silver wire) to one of the ground bars attached to the panel (don't bond the neutral to the panel ground). That would fix the worst of the mistakes here. I also don't see any noalox compound on the aluminum wires, but it may be there, just not visible. Without noalox, Aluminum wires are subject to corrosion, which leads to bad connections, which leads to over-heating.

If you decide to fix this before replacing the panel, be sure to turn off power to it at the breaker in your main panel.

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    Thank you for confirming that, and that the grounds don't appear to be bonded. I think I'll just get a real electrician who knows what they're doing to come and curse my predecessors. I wasn't aware of the aluminum coating required, so I'll make sure to get that looked at as well. – Scott Jun 22 at 19:08
  • Yeah, that's the bog-standard SqD tie strap design visible at the bottom of this Federal Pioneer interior, so yeah, the bars are tied together but not bonded to the case right now. Woops! – ThreePhaseEel Jun 23 at 0:23
  • Yeah, 3PH....what's the point of grounding and the tiny grounding buss-bars when there is no path back to the main panel?!?! One serious, real ground fault would "heat up" everything connected. Whoever wired this panel didn't know what they were doing. – George Anderson Jun 23 at 0:27

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