400W MH - BT28 vs. ED28
400W MH - BT28 vs. ED28
I think I know the answer, but I'm just guessing...
went to change some pole lights...fixtures are approximately 15 yrs old...
400W metal halide compact envelope...
Supplier didn't have ED28 lamps, so they sent us BT28 lamps...
replaced 1st fixture with BT28, didn't light...ok, maybe a ballast
moved on to 2nd fixture, replaced with BT28...again, no light...hmmm...
tried 3rd fixture, still no light with the BT28....something ain't right...
had 2 ED28 lamps on the bucket truck, took the BT28 out of the 3rd fixture, installed the ED28....lit right up...
I noticed that the Sylvania BT28's were labeled as 'Pulse Start', I'm assuming that the ED28's are not pulse start....and due to the age of the fixtures, the ballasts won't drive a pulse start lamp....
anyone know anything about this?