Lighting problem

[stefanv]

I have an eight bulb (36inch, 39W) t5 setup. The lighting fixture has 3 electronic (philips centium - one brand new) ballasts. 2 ballasts are connected to 6 lamps (3 lamps per ballast) and 1 to 2 lamps. 2 ballasts are on a single/separate power switch from the other single ballast. When I try to turn on the lights switch all but one set of lights turns on. The set of problematic set of lights will try to turn on but fail. You can hear a buzzing noise and they shut off. These are brand new bulbs. I have exchanged ballasts and try to reconnect wires connected to the ballast but nothing. I desperately need some help I don't know what else to do.

 

[sasquatch]

rotate all bulbs through the ballast that works to be sure bulbs are good, I suspect corrosin in the bulb holders but it could be a bad bulb

 

[stefanv]

I have tested all bulbs and they are fine. All i can think of is the connections ends that i did not check. Im suspecting a loose connection somewhere but I still cannot find it.

 

[sasquatch]

check each bulb holder, the copper wire can corrode and not contact the bulb pins, check the connectors at the ballasts while your at it?