Par power

[withoutfear]

Our Church was recently donated some american dj par 38's from an old coffee shop. Whomever ripped them out cut the power chord connectors off so they all need reterminating. each light has two wires. How would these terminate on a two prong plug from the hardware store. I purchased one two prong plug and both prongs are of equal size with no markings. Is there positive and negative with these lights or does it not matter.

[Frank DeWitt]

When a lamp socket is installed permanent the white wire goes to the shell and the black wire to contact in the center This is so it is harder to get a shock. (The white wire and shell should be at zero volts to ground.) If you want to be nice you could find a polarized plug. example http://www.stayonline.com/detail.aspx?ID=4733 ot put on a 3 prong grounded plug. This will force the correct polarity.

BTW White is the wide blade is the silver colored screw. black is the narrow blade is the brass colored screw.

Frank

[Steve Vanciel]

Originally Posted by Frank DeWitt

the white wire .... and the black wire

Unless the cords are European style with brown and blue wires.

SteveV

[RickR]

Take a light to the hardware store.
They can show you how, instead of telling. They can also select a plug with the proper strain relief for the cord.

If it were me, I'd get a new cord with a ground.

[withoutfear]

Yea I think I'll go with a the ground idea, it's a good one!
Thanks!

[Steve Vanciel]

Originally Posted by withoutfear

Yea I think I'll go with a the ground idea...

Are the units UL listed? If so, modifications will render them Not Listed. Also, you will become the "manufacturer" and bear the liability for any consequences.

Best course is to always repair items with the manufacturer's specified components.

SteveV
Orlando, FL

[Frank DeWitt]

Originally Posted by Steve Vanciel

Are the units UL listed? If so, modifications will render them Not Listed. Also, you will become the "manufacturer" and bear the liability for any consequences.

Best course is to always repair items with the manufacturer's specified components.

SteveV
Orlando, FL

The OP Said they have no plugs, so he wants to put plugs on them.

[Steve Vanciel]

Originally Posted by Frank DeWitt

The OP Said they have no plugs, so he wants to put plugs on them.

Yes, and also said the plugs were cut off of a two wire cord.

I was responding to the opinion of making it a three wire cord. That would involve rewiring the units and modifying the original design. What would the third, grounding, wire connect to? It could create a hazard rather than mitigate one. It would definately invalidate any UL (or other NRTL) listing.

SteveV

[Steve Vanciel]

Originally Posted by withoutfear

american dj par 38's ...each light has two wires. How would these terminate on a two prong plug from the hardware store. Is there positive and negative with these lights or does it not matter.

Back to the original post: Looking at www.americandj.com I see two different PAR38 units, one black and the other silver, with very different designs. The silver one is identified as ETL listed, the black one is not identified. I am going to guess that you have the black ones because the silver one is said to have a three prong power cord.
You can use a continuity checker to find which wire goes to the center contact of the lamp socket and which goes to the outer screw ring. Idealy, the "hot" wire should go to the center contact. Since there is no switch in the unit itself, there is not much practical difference as to which is which. Some lighting fixtures do not have different colored wires going to the lamp socket...just a green one to denote the grounding wire.

SteveV
Orlando, FL

[withoutfear]

I purchased a three prong plug but am leaving the ground unconnected as there is no wire to connect to it but this way there is no confusion or hazards in plugging the lights in backwards. Im also wiring the black to the copper screw and the white to the silver screw( both wires externally are black,one with writing,one without. Internally the black with writing goes to a black wire the other, a white wire. I am assuming black is positive) ...Is this a good remedy?

[Frank DeWitt]

That sounds like a good fix.
Black is at 120 Volts with respect to white AND to ground. Some times it is called hot. But because it is AC there is no positive.

[Steve Vanciel]

Originally Posted by withoutfear

...I am assuming black is positive...

All yes except don't assume. Use a meter to verify continuity on each wire.