Electronic Ballasts Help

[dandydan]

I have installed 2 250w electronic ballasts to a gieseman light fitting and was very disappointed with the light brightness over my reef, compared to the original german mag ballasts for the 4 week old BLV 250w 14000k DE tubes.

I purchased a lux meter and read at 9" from the tubes,
69000lux for the magnetic ballast and 36900lux for the electronic,
the magnetic volts to the tubes is 120v at 50Hz and the Electronic is 80volts at 80Khz. My supplier is bending over backwards to help, and even sending 2 new tubes which I dont think will make any difference. I dont have an amp probe small enough to measure current.

I am guessing that the lux meter says it all,
Any thoughts and help would be appreciated, or is this the way the bulbs last longer/and running cost is less on an electronic ballast??

Thanks

[dandydan]

Bump for a little advice please

[jackfrost]

Have your tried, or can you try, a different type of electronic ballast ?

Have you tried another set of the same type ?

What brand is it ?

The lux meter does not lie, and neither do you volt redaings. Something is not right with the electronic ballast that you have.

[dandydan]

Hi,
Thanks Jack, You are corrrect, like a young child I just needed confirmation, I know that PAR is the only measure for our purposes, but LUX can be used to compare the same set of bulbs, with different ballasts.

The only Electronic 250W ballasts, believe it or not available in the UK is from the U.S. I have tried every UK supplier I know.
these ballasts in question are dimmable Coralvue,
They say that the original gieseman magnetic ballast must have been overdriving the Bulbs??? But even if the Lux meter is only seeing green/Red or whatever its a rather large difference. Just might suggest that people with Electronic ballasts and cheap old Lux meters may want to do a comparison check.
The small saving in electricity costs is nothing compared to the loss of coral growth etc.

Thanks,
Dan