ballast replacement

[angharad]

I have a four lamp fluorescent fixture, two of the lamps were not lighting.
I ruled out the bulbs as the source of problem so replaced one of the
ballasts, the one connected to the two lamps which would not light. Now the
lamps connected to the new ballast work fine but the other two won't light!
Is this common? I am just wondering if I am wasting my time and $ buying
another ballast. BTW, its a rapid start ballast, MagneTek 446-L-SLH-TC-P.
Thanks for any help or advice.

 

[Don Klipstein]

I have a four lamp fluorescent fixture, two of the lamps were not lighting.
I ruled out the bulbs as the source of problem so replaced one of the
ballasts, the one connected to the two lamps which would not light. Now the
lamps connected to the new ballast work fine but the other two won't light!
Is this common? I am just wondering if I am wasting my time and $ buying
another ballast. BTW, its a rapid start ballast, MagneTek 446-L-SLH-TC-P.
Thanks for any help or advice.

Did you move any lamps around in the fixture? You may have had two
lamps out due to one lamp being bad - that's how the "traditional"
magnetic rapid start 2-lamp ballasts work.
You can have one lamp completely out and one lamp glowing dimly, and one
of the lamps may be bad. And the bad one is sometimes the dim one and not
the one that is completely out. You can sometimes have two lamps glowing
dimly with only one bad. The bad lamp usually (not necessarily,
especially not if the failure mode was not the usual one) has really
noticeable darkening of one end.

- Don Klipstein (don@misty.com)

 

[angharad]

I took the two lamp which were working and switched them with the two that
were not working. Its not the lamps but their position in the fixture.

 

[Victor Roberts]

I took the two lamp which were working and switched them with the two that
were not working. Its not the lamps but their position in the fixture.

Are you sure that you did not disconnect any of the wires connected to
the "good" ballast when you replaced the bad one? What you describe is
certainly not normal.

 

[Jeff Waymouth]

Check the green ground wire connections from the ballast to the fixture
( Steve Squillace is hollering "LUMENAIRE!" in my inner ear ;>)} ) if
the ballasts are equipped with seperate ground wires and don't pick up
the ground through ballast case. Also it's a good idea to check the
actual fixture grounding itself..

Jeff Waymouth (with a new set of "railroad tracks" up his belly!)

 

[Victor Roberts]

Jeff Waymouth (with a new set of "railroad tracks" up his belly!)

Hi Jeff - glad to see everything went well.