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JB Thompson
06-07-2010, 05:11 PM
In this downstream cabinet, none of the equipment grounds were visible. The stranded aluminum wire (shown in the photo) and the way it is attached is confusing to me. It came from outside the cabinet and terminated in the lug that's visible. The other one disappeared out of the other side of the cabinet. The buss bar does not appear to be bonded to the cabinet; however, the stranded aluminum wire on the left side of the photo is touching that back of the cabinet.

Once again, thanks for the help.

Bruce

PS. Today was almost a Trifecta! A mean-looking Zinsco main panel and a Federal Pacific subpanel. This was the Square D subpanel.

PPS Yes, I wrote up the tripped breaker and the double-lugged neutrals.;)

Jim Port
06-07-2010, 07:01 PM
Do you have a picture of the overall panel?

JB Thompson
06-07-2010, 07:08 PM
These are the only other pics I took of it

Jerry Peck
06-07-2010, 07:21 PM
In this downstream cabinet, none of the equipment grounds were visible.

Because the white conductors say "TW" on the insulation that means they are conductors pulled in raceways, with the raceways being metal (most likely) the raceways would be the equipment ground path, so no ground wire would be required.


The stranded aluminum wire (shown in the photo) and the way it is attached is confusing to me. It came from outside the cabinet and terminated in the lug that's visible. The other one disappeared out of the other side of the cabinet. The buss bar does not appear to be bonded to the cabinet; however, the stranded aluminum wire on the left side of the photo is touching that back of the cabinet.

Bruce, not quite sure what you are describing in the last part above.

JB Thompson
06-07-2010, 07:28 PM
Apparently, I've only seen stranded wire pulled in conduit and not solid. Thanks

Regarding my "bonding" question: in the first photo, the stranded aluminum that is to the left of the white conductors is lugged with the white conductors AND physically touching the back of the cabinet. Is this bonding the sub?

Bruce

Corey Friedman
06-07-2010, 07:45 PM
In this downstream cabinet, none of the equipment grounds were visible. The stranded aluminum wire (shown in the photo) and the way it is attached is confusing to me. It came from outside the cabinet and terminated in the lug that's visible. The other one disappeared out of the other side of the cabinet. The buss bar does not appear to be bonded to the cabinet; however, the stranded aluminum wire on the left side of the photo is touching that back of the cabinet.

Once again, thanks for the help.

Bruce

PS. Today was almost a Trifecta! A mean-looking Zinsco main panel and a Federal Pacific subpanel. This was the Square D subpanel.

PPS Yes, I wrote up the tripped breaker and the double-lugged neutrals.;)

Hello JB,

As best as I can see from the pix, here is what I think is present. The feeder to this panel is the old style service entrance “rope” cable that contains two hot conductors and an un-insulated neutral. That is the larger aluminum conductor at the neutral bus.

There is a second, smaller gage rope cable (smaller aluminum conductor) with the two hot conductors at the top left breakers and an-insulated neutral. This circuit is likely running to an electric clothes dryer or electric oven.
This is an old way of doing things but is common for its age.

The neutral should not be bonded to the enclosure. When panels were wired liked this (back in the day), it was permitted to have the neutral / grounds tied together for circuits like an electric oven.

Most electric ovens made today come with a neutral / ground bonded together with instructions to seperate them or leave them bonded depending on the wiring available and based on certain years when the practice stopped (mid '70's?).

Others I’m sure will chime in and pick on the paint, and lack of 2 pole breaker if in fact the top left circuit is for an electirc appliance.

By the way, what is a downstream panel? Is this installed in river? :)

Sincerely,

Corey

P.S. Are you saying Square D is a bad thing?

Jerry Peck
06-07-2010, 07:54 PM
Regarding my "bonding" question: in the first photo, the stranded aluminum that is to the left of the white conductors is lugged with the white conductors AND physically touching the back of the cabinet. Is this bonding the sub?


Unintentionally bonding the panel, yes.

I am wondering if that center, slotted head screw, even though it is not green, may be a bonding screw to the back of the panel enclosure?

Besides, if those uninsulated conductors 'are not' "neutral" conductors ... they are not allowed to that neutral terminal bar, and if they are indeed "neutral" conductors, then - all neutral conductors are required to be insulated (except for the neutral/ground in service entrance conductors).

To bond a sub you really need to get into deep water ... or are you already in deep ... :D

You did, of course, write up the multiple tapped neutrals.

JB Thompson
06-07-2010, 08:15 PM
Thanks for the help guys.

Jerry: Yes I did, see 1st post. And I always seem to be in deep water or doo-doo:D

Corey: Wish I knew what that upper left breaker was for....no labels anywhere. Not saying anything bad about SqD