VL2500 Spot: Another Lamp Issue

[GoboMan]

Hello again!

Ironically, after posting today about striking and re-striking lamps, I have a VL2500 exhibiting a weird lamp issue.

When it powers up, all sensors and motors test out fine (and fixture status is OK), but the lamp is flickering. The beam kind of looks like one of those old orange electronic candle "flicker" bulbs, and the hotspot keeps jumping around the area of the beam. I tried replacing the lamp, but it does the same thing.

Could this be a failing ballast or ignitor?

 

[LightingNerd217]

Was there ever an answer to this? I'm experiencing the same flicker and hotspot jump in several of my VL2500s.

 

[JD]

If the lamp has been changed then that only leaves the ballast. I would not think of it being an ignitor problem as they develop very little current compared to what is flowing in a lamp that is already struck. If this is an E-ballast, I would inspect it for thermal damage around the current sense resistor/circuit.
A hunch would be there is a weak area of design in the ballast as this issue is coming up in several units.

 

[Erik456]

Will agree with above posters, first is new lamp, next is new ballast.

 

[macsound]

I've bought alot of used moving lights over the years. Typically if they're used in a permanent install, they hang the same way and do the same routine every day. Believe it or not, gravity affects the arc in the lamp.
What this means is maybe one contact inside the envelope is worn one way and the other contact is worn a different way.
Sometimes I'll have a lamp not strike facing down, but rotate the head up and it strikes just fine for another year until the lamp is actually toast.