Sub-Panel Wiring w/ AC Cable

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nyc_terp

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I've referenced this forum many times in the past for my general knowledge but this is my first post.

With this whole self-isolation thing going on, I find myself wondering about a few items and figured I'd post to see if I could get them answered since I have nothing but time for now.

First, I live in NYC and I've been exposed to construction my whole life but don't know too much about electrical. Many single family residential projects I've seen in NYC use AC cable, that is the cable that uses a combination of the metal jacket and thin bonding strip as the equipment ground. My question is, if that jacket and bonding strip acts as the equipment ground, on a sub-panel, there shouldn't be any ground wires attached to the ground bus bar except for the one to the grounding rod and the one to the main panel, correct?

Second, I've seen a grounding bus bar (https://www.grainger.com/product/49K823?cm_mmc=PPC:+Google+PLA) used in some applications. Is that acceptable to use that at the main panel and have the main ground connected to that then back to a grounding rod as well as the incoming water service?

Thanks in advance.
 
Welcome to the forum. If the entire building is wired with ac that has the aluminum strip then there isn't any reason to have wires connected to the ground buss. The grounding electrode conductor to the ground wire should not be connected to a sub panel unless that panel is in a detached structure from the service.

Yes, in some larger buildings you may seen a ground buss bolted to a building near the service where the grounding electrode conductor's are attached.
 
If the entire building is wired with ac that has the aluminum strip then there isn't any reason to have wires connected to the ground buss. The grounding electrode conductor to the ground wire should not be connected to a sub panel unless that panel is in a detached structure from the service.
Click to expand...

So to be clear, in the main panel, assuming the neutral bus bar and ground bus bar are bonded (which they should be), there should only be neutral wires connected to either? Again, that assumes the ground bus bar has a ground wire connected to the grounding electrode conductor.

Then in the sub-panel, the ground wire should be connected to the grounding rod only if its in a detached garage from the main service?
 
If the entire building is wired with AC cable in the main panel the neutral wire from the branch circuits would be connected to the neutral bar, the ground bar would be empty, the neutral bar would be bonded to the panel enclosure. The neutral bar would have the incoming neutral from the service connected to it as well as the GEC. If an NM circuit was added to the main panel neutral goes to the neutral bar and ground to the ground bar.

In a sub panel the neutral bar is floating, isolated from the panel, otherwise everything is the same. An added NM circuit would have it's ground on the ground bar.
 
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