Are the grounds & nuetrals properly isolated in the photo below. They are on seperate parts of the bar but the bar is connected.
This is a Auxilary panel and not the main distribution panel.
Thanks
You answered your own question - NO.
The neutrals must be isolated from the enclosure. The grounds must be bonded to the enclosure.
You cannot meet these requirements if the “bar is connected.”
Bump
Thanks
I usually know the answer but I like to make sure before I submit the report.
This was a pre list & I want to make sure there is no second guessing on my end.
Thanks Jeff I value you expert opinion.
What is the hazard of bonding the grounds & nuetrals?
Q. Given the physical and electrical nature of the connection between those two panels, what is the difference between this and a “split bus” service panel where with the lighting section’s bus is fed via a breaker? Is the second panel in this set up considered a “distribution” panel, or part of the service panel?
A parallel path of current which may energize panel boxes, conduit, etc. etc.
The split bus would be considered within, or part of, the service equipment. . .
The operative language is “Objectionable Current over Grounding Conductors”. You don’t ever want circuit current flowing in any grounding conductor, including the main bonding jumper.
That means that even if this is the main panel, you don’t want white wires on supplimental buses that are screwed directly to the enclosure. Their path to the transformer X0 is through the bonding jumper or green screw
I thought that in a main panel, if you happen to have two bonded grounding/neutral buses, it doesn’t matter where the grounded and grounding conductors go (i.e., that you could mix them on the two buses).
If the grounding bus is simply screwed to the can you are sending circuit current through the enclosure. That in not correct.
Okay, I’m trying to understand. Assume that there is only one bus in the main panel, and that both grounded and grounding conductors are attached to that bus. Isn’t that bus bonded to the enclosure? If so, doesn’t that mean that return current, even though it is flowing back through the neutral line to the center tap on the transformer secondary, is also present on the panel? Or rather does the fact that it is flowing back to the tap mean that there is no current on the panel?
Doesn’t the green screw bond the bus to the enclosure?
I think maybe you’re confusing “main panel” and “sub panel”
The point is you are never supposed to impose circuit current on the enclosure … period. If this is not part of the neutral bus(s) it should not have white wires on it. The main bonding jumper (green screw) is not listed as a circuit conductor.
What you will have it what is called objectionable currents which would cause the enclosure to be energized. This is a big problem with remote distribution panels.
Where’ve you been big guy?
Hey Jeff,
I am sitting in a hotel room in Kansas City,KS ending up a 3 days of seminars.
Had a nice turn out…This is the only hotel I actually got internet connection from.