Lithonia 400w Metal Halide Fixture question...

[NolaTigaBait]

it came factory wired for 277 and i changed the configuration to 120...there were no schematics with the fixture...checked it today it was working and there was a considerable amount of heat present at one time(it looked like the photo cell wire and the leads from the ballast were cooked)...is this the result of me mis-wiring the fixture or a defect?...i think its a Lithonia wall mount hrw series fixture

 

[NolaTigaBait]

check that TWR series

 

[DanZ]

The TWR series isn't available as 277V only. It's available as 120V or with option code TB it has a multi tap ballast. I'm leaning toward mis-wiring. Check for a wiring diagram on the ballast.

 

[NolaTigaBait]

that's the problem....there is no wiring diagram

 

[S'mise]

They do radiate a lot of heat normally but obviously leads should not be melted. I don't know if this helps but, The tap wires are usually marked with the voltage on them. Make sure the unused wires are isolated (No double taps). The wires off the balast are usually white or yellow with a black and red for the fuse in line. I would do an amp test to make sure the ballast was not shorted.

 

[NolaTigaBait]

s'mise...i'm kinda learning on the fly here...could you explain how to test the ballast and can you test the bulb?

 

[electricalperson]

s'mise...i'm kinda learning on the fly here...could you explain how to test the ballast and can you test the bulb?

ok heres how to test the ballast.

measure voltage at the socket. with a MH you dont have an ignitor inside there should just be the transformer and capacitor.*set your meter to the 1000v setting first.* you should read about 285 - 320 volts at the socket. you can also check the capacitor with a capacitor tester or the capacitance function on your meter
if its not right check the capacitor

if you measure low resistance that gradually increses and goes to OL the cap is fine. if it doesnt change or starts at OL the capacitor is open and needs to be fixed. if its very low and doesnt change its shorted

**make sure you discharge the capacitor before touching it. i was reminded of that last week while testing a capacitor on an air compressor**
\***another edit if you have HPS ballasts you can test it pretty much the same way just disconnect the ignitor or you might destroy your meter. the book troubleshooting electrical/electronic systems explains testing and troubleshooting of HID fixtures pretty well if you want to learn about it***