ECN Forum Forums Photo Discussion Forums Violation Photo Forum C.T. Cabinet Shorted

People really use wood for this....no insulation between the plywood and the lugs?? No way!!!

All wood has some moisture in it. This varies with the environment over time. The stuff (chemicals, salts, blah, blah) in the wood allows it to conduct electricity right. It's just a question of how much current flows.

If I did this in an industrial control cabinet the inspector would ask me what I was smoking....Convenience should be no excuse by the poco over a safe installation. Dang!!

Do ya suppose if the poco started following some type of electrical code that our rates with triple?
Good...Fast...Cheap; pick two.

RSlater,
RSmike

Ok then, It would have made sense if those parallel conductors were to account for VD in a long run, but with the panel being just on the other side of the wall, am I missing something?

How about plexyglassfor the back and then another half plexyglass with spacesrs, over the lugs?

Jeepmudman:

First off, welcome to ECN!

Plexi might be o.k., certainly a better insulator than wood, but if I was the AHJ, I'd still fail it. Plexi is sensitive to temperature and would readily deform/melt if the lugs got too warm. Now as to a plexi cover that would be o.k. as long as it was not in direct contact with the lugs.

In general:

An issue that I have now noticed and no one's questioned: Aren't the parallel conductors all supposed to be the same length? (Not only each phase/neutral, but the overall set.) From the looks of this install, I'd say no. Another red sticker?

It also makes no economic sense either, for if the panel is just the opposite side of this cabinet, wouldn't a single run of the proper conductor size cost less than the two runs installed?

Alan:
We use a listed/labeled UTILITY Approved CT cabinet, most are NEMA3R. 800 amp rated.
Interior is setup to the UTILITY specs, with brackets, etc for support of CT's. Some CT's are 'bar type, four stud mounted to cabinet rail, and landing pads for line/load lugs. Some are 'donut type', with mounting base to match cabinet brackets.

PSE&G requires non-magnetic, 1/2" dia., stainless bolts, nuts, flat washers, and belleville washers. Utility Wiring Inspector checks hardware with magnet.

Larger (over 800 to 1200 amp) CT cabs are special order fabricated to Utility specs, basically a larger version of the above.

NONE have any wood. No grounding/Bonding conductors are allowed within the CT cabinet, bonding lug is on exterior, IF neutral conductor is not present.

Kenny also said....'know when to RUN'

John

luke,

secondary wiring (customer wiring) is sized as per table 310.16. paralleling has nothing to do with VD.

thank you for the welcome :MXSLICK. This is a great place.

jeepmudman,
Welcome mate!,

Only conductors actually electrically in parallel need to be of the same length, diameter, insulation and conductor material. Separate phases (or the neutral) could be of different characteristics. The neutral could be smaller, shorter, etc. Phase A could be copper and Phase B aluminium, etc. But all conductors of Phase A need to be the same, etc.

-Jon

Here in the city of Austin Tx, we do not allow any splicing of the main conductors going through window ct's in any ct box; must be pulled through in one piece.
Also we don't allow bare energized lugs mounted on wood-an instant red tag.
B. Parks