thanks for the info from everyone .. I'm sorry for my confusion in the original post. We are using quad tap ballasts at 208V. I can only hope that the electrical contractor is actually checking the correct tap is being used. At 30', we have no easy way to do this ourselves. The original installer was a large electrical contractor co. that the general contractor had used as a sub. They keep saying they've never had this type of problem on any other job. So much for that. We'll try someone else.
One last question ... just how much life should you expect from these types of ballasts? and bulbs?
