I don't understand the bonding at my main disconnect. My problem is that my main panel in the house was wired OK with the neutral bonded to ground. The power company added a disconnect box below the meter box. I noticed the disconnect they installed doesn't have the neutral bonded to ground. Am I going to have a problem? From what I read my main panel is now a sub panel because they added a disconnect? I am wondering why they thought it was OK.
Electrical – Does adding a disconnect box below the meter mean that the service panel is now a subpanel
electricalgrounding-and-bondingwiring
Related Solutions
The first configuration seems correct. The second is definitely wrong, and the third may just be a waste of wire.
If the spa has only 240 volt loads, then a load side grounded (neutral) conductor is not required. Which means you won't have to connect the grounded (neutral) pigtail from the GFCI breaker.
If you really wanted to, you could should install a grounded (neutral) as in the third configuration. This might be worth doing, if you might add 120 volt loads in the future.
Check the manufacturer's installation instructions for both the spa pack, and the breaker to be sure. But you should just be able to cap the pigtail with a twist-on wire connector.
After further review
According to Schneider Electric's faq, the line neutral must be connected. So configuration 3 is the only way to go.
On 2P 15A to 50A the GFI breaker will work with or without a load neutral wire. However, if there is no load neutral wire the breaker neutral (white curly wire) must still be connected to the panel neutral.
On 2P 60A and all 3P (QO only) there is no load neutral wire connection on the breaker. Again the breaker neutral (white curly wire) must be connected to the panel neutral.
Ground and neutral are not parallel neutrals. I know it looks that way because they're bonded in the main panel. But shift into a different way of thinking about the purposes of the 2 wires. Think of the ground solely as a safety shield.
Let's try a few pairs of examples. The first is Code and the second bonds at the sub-panel also. The orange glow is on things which are "hot".
Seems awesome right? Poor old Code Man is in the dark. His power tried to return via neutral, and neutral is broke, so the power failed. Rogue Man is one happy guy and his life isn't disrupted. Ground is working great as a "backup neutral". He doesn't even know he has a problem!
Of course, ground is a thinner wire, so it might overheat, but so what? Or, what if both ground and neutral were cut?
Code Man is still in the dark and he's still gotta fix those wires. Rogue Man is dead.
In Code Man's installation, the hot went through the bulb, looking for neutral. It didn't find it, so it pulled the neutral up to 120V ( not enough power for useful work, but plenty to shock). It did the same for Rogue Man, but since he tied neutral to ground in the sub-panel, ground is now also 120V, including the service panel cover and the switch plate cover screws.
Suppose the sub-panel has its own ground rod. That doesn't help much. Earth tends to have high resistance, so the cover screws might be 103V instead of 120V.
I have the good fortune of working in EMT conduit in a steel building, which naturally forces the entire conduit system to ground. Ground is never part of the circuit in any way whatsoever. So I get to see it as intended, as a protective "shroud" around all things electrical.
Ground isn't quite yet a perfect envelope. It is in new work, but we still have a lot of old wiring out there that is not practical to outlaw entirely - such as NEMA 10 and switch-loop smart switches which poach ground as a neutral.
Why bond neutral at all?
That's a GREAT question. Not bonding ground would give you an isolated system. And that makes a lot of sense in some ways, like solving some of the problems you see above. But it has other disadvantages. I go into depth about that here.
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Best Answer
If the power company did not change the bonding point, you still have a main panel ("the one with the bond in it.")
So long as there's only one, the location of the bond can and does vary with the preferences of the power company, mostly. Mine is inside the meter box, so my panel is wired as a sub-panel.
On a typical panel run from a meter and bonded in the panel, the meter itself is a disconnect point that's upstream of the bond, and that's not a problem.
You should realize that the neutral and ground conductors are not interrupted by a disconnect, so the bond in your panel is still effective even with a disconnect upstream of it.
If the power company had opted to move the bond point, they would have needed to rewire your panel - a considerable expense (for them) and inconvenience (for you) they avoid by not changing the bond point.