[Knucklez]

are your lights on a dimmer switch?

 

[Bud Cline]

...how old are the light fixtures. In the older fixtures the flickering can also be cause by bad starters. The starters (if the fixture has them) are the little silver-gray cans/tubes about the diameter of a nickle. They twist out and in and can be purchased at any hardware store.

If the fixtures don't have starters then maybe the ballast(s) are going bad or not capable of supporting the late-model bulbs. If that is the case it is sometimes less costly simply to replace the fixture totally.

 

[kbsparky]

Did you replace T-12 bulbs with the new T-8 type? Unless you changed the ballast, you could have operational problems by making such a substitution....

 

[frenchelectrican]

Also what more with some of the T-12 ballast will not run 48" 25 watt bulbs at all { I have see this more than once in both USA and France side }( some 34 watters may not work with some T-12 ballast as well especally on cool days or have A/C blowing on the bulbs that can compound it )

Double check the label on ballast to make sure you are using proper bulb it will make a big differnce on operation.

Merci,
Marc

 

[dmxtothemax]

Have you checked that the supply is correct and stable ?

The older style floro tubes operated on a slightly lower voltage
than the newer quick start tubes.
You can tell the difference by looking at the diameter
of the floro tube, the older ones were larger in diameter.
So if you put a modern quick start tube into a fitting
designed for the older style tubes, it might not work correctly.

Also modern tubes do flicker more than the older ones,
Because they have taken the mercury out of the tubes.
Some new tubes will flicker for a short time (15 mins )
at first use, but this will fall away to a low level.
It is perfectily normal for them to flicker a little bit.
probably as a result of minimilist design and high efficency.