Metal Halide experts??

[pmanton]

Here at the airpark, a chap suddenly lost some storage space and got rid of some recessed lighting HID luminaries. These are Columbia lighting 320W pulse start metal halide fixtures.

Pretty ugly things--but for the price I figured on hanging them high up in my hangar where looks don't count.

I wired the ballast for 120 and fired one up. After the lamp came up to max brilliance I measured the current draw. Surprise around 2 amps instaed of the 3 or so that I expected. I checked my clamp on with another--same. Tested another fixture--same results. Wired one for 240--current draw about an amp--same results. And max briliance seems a bit dim from what I remember with the old 400 watt MH fixtures. (I retired in 2000)

I'm wondering if the ballasts are designed to limit current to the lamp in order to keep heat down since they're recessed fixtures. Since another fixture tested the same I discount a bad ballast.

I think it would be a waste to hang these fixtures if they're not going to give me 320 watts of light.

Thanks

Paul
N1431A
N83803
2AZ1

 

[Old Geek]

Whatever you do with those things, make sure they are properly grounded. If the internal insulation or circuitry is flawed and they aren't grounded, touching them could kill you in an instant.

 

[gismo]

Here at the airpark, a chap suddenly lost some storage space and got rid of some recessed lighting HID luminaries. These are Columbia lighting 320W pulse start metal halide fixtures.

Pretty ugly things--but for the price I figured on hanging them high up in my hangar where looks don't count.

I wired the ballast for 120 and fired one up. After the lamp came up to max brilliance I measured the current draw. Surprise around 2 amps instaed of the 3 or so that I expected. I checked my clamp on with another--same. Tested another fixture--same results. Wired one for 240--current draw about an amp--same results. And max briliance seems a bit dim from what I remember with the old 400 watt MH fixtures. (I retired in 2000)

I'm wondering if the ballasts are designed to limit current to the lamp in order to keep heat down since they're recessed fixtures. Since another fixture tested the same I discount a bad ballast.

I think it would be a waste to hang these fixtures if they're not going to give me 320 watts of light.

Thanks

Paul
N1431A
N83803
2AZ1

How long did you let it warm up before measuring the current?

 

[pmanton]

How long did you let it warm up before measuring the current?

At least 10 probably closer to 15. I fired it up in the hangar, watched it for a few minutes, then went into the house, did some stuff and came back out and measured the current draw.

Paul