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Sam Morris
03-12-2015, 02:07 PM
Inspecting this 200 amp service panel, my question is what is the copper thing behind the bus bar called? Is it the bonding strap. Is it supposed to be connected to the bus ?
Jerry Peck
03-12-2015, 05:18 PM
Yes that bonding strap should be connected between the enclosure and the neutral/grounding terminal bar, but ... with all those grounds and neutrals in the same terminals (which is not allowed, never was) ... and being as that is a Zinsco panel ...

... that lil' ol' missin' bondin' strap ain't really nutin' much ta wory 'bout. :)
Dave Ruth
03-22-2015, 05:20 PM
... with all those grounds and neutrals in the same terminals (which is not allowed, never was) :)

Were grounds and neutrals ever allowed in the same terminal on bars where terminals were listed to accept 2 wires?
Jim Port
03-22-2015, 05:25 PM
Not in accordance with the panel label instructions.
Dave Ruth
03-22-2015, 06:06 PM
Not in accordance with the panel label instructions.
I remember a few years ago when NEC added rule requiring only one "neutral" in a lug. But I don't remember seeing such a prohibition on labels of panels (before then). UL evidently required panel manufacturer to provide enough lugs for each "neutral" to have it's own, but was it against rules to put 2 in the same hole (on bars where more than 1 wire was allowed in a hole)?
Jim Port
03-22-2015, 06:14 PM
Even under the panel label instructions it was one neutral per hole.

- - - Updated - - -

Even under the panel label instructions it was one neutral per hole.
Jim Luttrall
03-22-2015, 06:19 PM
Inspecting this 200 amp service panel, my question is what is the copper thing behind the bus bar called? Is it the bonding strap. Is it supposed to be connected to the bus ?
Forgetting about the other issues already mentioned, the panel enclosure and grounding terminal bar should be bonded to the neutral terminal bar with the strap you asked about "IF" this is the service equipment.
"IF" it is NOT the service equipment then the strap should NOT be connected.
Jerry Peck
03-23-2015, 03:32 AM
Were grounds and neutrals ever allowed in the same terminal on bars where terminals were listed to accept 2 wires?


Not in accordance with the panel label instructions.

For decades, the panel instructions did not address the issue, nor did the code address the issue, however, UL Standard 67 (I think it is UL 67) to which the panels are tested and listed addressed the issue and it was not permitted ... the problem was this: What inspector, electrical contractor, or electrician read the UL standards? Eventually some did, and that is when the issue started being addressed by some inspectors, and it eventually was added into the code.