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#115004 - 07/31/03 06:23 PM Air Compressor Disco
Webmaster Offline


Registered: 10/07/00
Posts: 3142
Loc: NY, USA
In the process of relocating an air compressor to make room for a service upgrade I encountered this. The compressor is 3ph. 480v w/120v coil in contactor. The service, as well as the rest of this plant have too many violations to list. More pics. to follow.

Donnie McMayon~aka txsparky

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#115005 - 07/31/03 08:34 PM Re: Air Compressor Disco
txsparky Offline

Registered: 05/25/01
Posts: 578
Loc: Magnolia,.Texas U.S.A.
I guess whoever hooked it up only had 2 colors of wire. Blue for line and gray for load. The neutral that was ran into the Disco. for the control circuit on the starter coil was capped off. 1 side of the coil was attached via a jumper wire to a sheetmetal screw in the starter enclosure.It must have picked a ground up through this piece of 1/2" greenfield via the 3/4" EMT set-screw connector. No EGC.

#115006 - 07/31/03 08:50 PM Re: Air Compressor Disco
NJwirenut Offline

Registered: 09/15/01
Posts: 816
Loc: Bergen County, NJ
If this installation was 480V, how was the 120V contactor coil powered? With one side connected to ground thru the greenfield, it would still see 277V from any of the 3 phases, assuming a wye system. Was there a separate source of control power from somewhere? Is that what the red wire does for a living?

At any rate, a nasty looking install....

#115007 - 07/31/03 08:57 PM Re: Air Compressor Disco
Bill Addiss Offline

Registered: 10/07/00
Posts: 4196
Loc: NY, USA

I was looking at the Yellow Tape and thinking it was a butt splice, but thinking the wire looked long enough. Too much coffee I guess ..

Is that an EMT connector on the bottom?

#115008 - 08/01/03 08:47 AM Re: Air Compressor Disco
SvenNYC Offline

Registered: 08/19/02
Posts: 1685
Loc: New York City
You're right Bill, it does look like a crimp-on buttsplice connector. But (d'oh) if you look closer, you can see the edge of the yellow tape where it didn't stick.

Shouldn't phase tape be applied closer to where the wire enters the terminals -- in other words, right underneath it?

That way it's visible at a glance and not subject to confusion when you try to play the "what wire goes where" game?

#115009 - 08/05/03 08:47 PM Re: Air Compressor Disco
classicsat Offline

Registered: 11/23/02
Posts: 449
Looks like the red wire may be 120V power for the contactor.


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