Hello all,

I use the Osram HQI-BT 400W lamp with my eballast that I bought on lumenlab. The ballast makes a loud buzzing noise all the time it operates.

I wonder if other people use this combination and have the same problem.

I have tested it with two eballasts and two differend hqi-bt lamps and two differend mogul bases, same thing.

Thanks for helping,

Ilia

Eballasts should be silent. Full stop.

I have the same bulb as you with a coil ballast, and once its warmed up its inaudible. The Osram bulb pretends to be a HPS bulb, but the lumenlab ballast is capable of running them. Is it a lumenlab eballast you are using, or another type?

Eballast should be quieter than coil ballasts but I would not expect them to be silent.

The idea is they are as good as silent, since the frequency they are producing is far too high to be audible. One of the main supposed bonuses of an eballast is that it should be significantlly quieter than a coil ballast, and coil ballasts are really not very loud. I can't hear mine at all over the noise of the fan.

what could be wrong?

How is it mounted to the box, the ballast may be vibrating the side of the box which now works as a echo chamber, amber, ber, r.

with screws, it gave the same noise when it was not on the box but on the ground. Maybe the lamp is not compatible...

these E-ballast have been having problems lately. It could just be the E-ballast itself not functioning properly. I know other people have had noise problems to.

interesting info on the pdf of the lamp posted by the trhead starter;

lamp wattage on HPS gears 420W
lamp wattage on MH gears 360W

I would say it is talking about magnetic ballasts thought.

More interesting is
Luminous Flux (100 hrs): 32,000lm (SON ballast), 25,000lm (MB ballast)

MH ballast is only 78% as bright as HPS ballast.

Yes, Rox, those ratings do not apply for the eballast, which is designed to run both HPS and MH bulbs.

The Osram bulb, although primarily for HPS ballasts, is designed to work on either type of ballast, but when used with a MH ballast it has a higher colour temperature (I think) and considerably less lumen output.

now a metafisic question, what wattage/lumens would you expect on a HID universal (HPS & HM lamps compatible) e-ballast?

I would expect the eballast to maintain a constant 400W to anything attached to it, and therefore I would expect a lumen output somewhere between the 2 values, probably closer to the higher one since eballasts are better at running the lamps efficiently.

Thanks for the replies.

I contacted the eballast factory and they say that it might be the lamp too. They are going to ship me a new Osram lamp, I don't know which one yet, and I am going to ship them mine, so they can also test it.

Who knows...