Welding Shop lighting problems

[travis3710]

I am not new to the forum, but I do not post alot I mostly read.
I am an electrical contractor and I have a customer with a lighting problem in his weld shop.
Sixteen foot ceilings with eight foot, two lamp, HO fixtures, 277 volt, Magnetic ballasts.
welders run off of 480 and 277 volts.
The lamps are rated at 2000 hours. He gets on average 500 hours.

Lighting rep. he talked to says possible frequency interferance between welders and ballasts.

 

[iwire]

F96/T12/HOs with magnetic ballasts are pretty much expired technology.

My suggestion is to either rebuild the existing or replace the existing with 4 lamp T-8 electronic fixtures.

I also suggest switching these few fixtures to 120 if they are not already to get some isolation between them and the welders supply voltage.

The fixtures will be as bright, use less power and the customer may well get a rebate from the power company for changing over.

 

[travis3710]

Thanks for the advice Bob, but the customer does not want to pay to upgrade the lights. I think I have figured out the problem. The ballasts are VHO and he is using HO lamps. Bad idea.