Hey everyone!

I just made a cool discovery with my 100W Lithonia "PSMH" floodlight.  As I mentioned in a previous post, these Lithonia/Caster Lighting 100W "PSMH" floods really have 100W H38 MV ballasts inside, but simply have an added ignitor tap.  Earlier, I simply unscrewed the inner reflector and disconnected/capped off the ignitor's neutral wire when I wanted to run MV, but after doing this for so long, the stranded wire would fall apart and I'd have to cut back more and more wire to the point where I'd render the fixture useless. 

After giving it some thought, and knowing I wanted to run BOTH PSMH and MV on the same fixture, I had the ingenious idea to add a switch to the ignitor, thereby eliminating the hassle of having to keep disassembling the fixture and gradually ruining the wiring.  So, I simply bought some fiberglass and mica-insulated (heat-resistant) wire, which I fed through the arm of the fixture into the gang box I have the fixture on.  I then connected those wires to a switch with wired leads, which I mounted on the outside (by its wires and with some electrical tape to reinforce it) of the gang box with an NM clamp.  From there, I spliced the main neutral wire going from the ballast to the ignitor and socket, connected one end of the added wire to the socket/ballast side, looped it around to the switch, and then connected the other end back to the ignitor's neutral.  In the end, this setup worked amazingly well!

NOTE: Make sure to use ONLY 600V+ rated switches, even when only switching the neutral on the ignitor.  While 4KV pulses shouldn't pass through the neutral on a correctly-wired fixture, a 600V switch is still recommended and should be fine when using in a temporary application.  Anything else rated lower may be damaged or cause arcing if connected to the high-voltage ignitor.  Note the fixture's factory wiring is also 600V, too, so this shouldn't be any problem.

I just wanted to share this with you real quick, as it is a relatively easy (and super convenient) addition to these aforementioned fixtures.

If you cannot find such switches at an affordable price, you could possibly make a plug in ignitor where you can unplug it when not needed.

If you cannot find such switches at an affordable price, you could possibly make a plug in ignitor where you can unplug it when not needed.

Very true...  In my case, though, I was able to find a switch for under $10, and wanted a "cleaner" appearance.  It would have taken several other purchases to make the plug-in ignitor.  And this way, the ignitor is still built-in; whether or not I want it on is literally as simple as flipping a switch...

Sometimes, like on one of my cobraheads, I'll mount the ignitor switch on the inside of the luminaire. In that case I had to make a bracket utilizing some existing mounting bosses for the switch. Works pretty well as you have to open up the cobrahead to change the lamp anyway and that way you avoid drilling through the luminaire.

Hey everyone!

I just made a cool discovery with my 100W Lithonia "PSMH" floodlight.  As I mentioned in a previous post, these Lithonia/Caster Lighting 100W "PSMH" floods really have 100W H38 MV ballasts inside, but simply have an added ignitor tap.  Earlier, I simply unscrewed the inner reflector and disconnected/capped off the ignitor's neutral wire when I wanted to run MV, but after doing this for so long, the stranded wire would fall apart and I'd have to cut back more and more wire to the point where I'd render the fixture useless. 

After giving it some thought, and knowing I wanted to run BOTH PSMH and MV on the same fixture, I had the ingenious idea to add a switch to the ignitor, thereby eliminating the hassle of having to keep disassembling the fixture and gradually ruining the wiring.  So, I simply bought some fiberglass and mica-insulated (heat-resistant) wire, which I fed through the arm of the fixture into the gang box I have the fixture on.  I then connected those wires to a switch with wired leads, which I mounted on the outside (by its wires and with some electrical tape to reinforce it) of the gang box with an NM clamp.  From there, I spliced the main neutral wire going from the ballast to the ignitor and socket, connected one end of the added wire to the socket/ballast side, looped it around to the switch, and then connected the other end back to the ignitor's neutral.  In the end, this setup worked amazingly well!

NOTE: Make sure to use ONLY 600V+ rated switches, even when only switching the neutral on the ignitor.  While 4KV pulses shouldn't pass through the neutral on a correctly-wired fixture, a 600V switch is still recommended and should be fine when using in a temporary application.  Anything else rated lower may be damaged or cause arcing if connected to the high-voltage ignitor.  Note the fixture's factory wiring is also 600V, too, so this shouldn't be any problem.

I just wanted to share this with you real quick, as it is a relatively easy (and super convenient) addition to these aforementioned fixtures.

Did you use an amp meter to discover that the ballast inside the lithonia flood is underdriving the 100w MH lamp?

I did a test a few months ago (seen here) involving two Caster 100w PSMH ballasts (the MH100 and MH100/4 ballasts), and i came to the conclusion that the MH100/4 ballasts was a true M90 ballast while the more common MH100 ballast was a modified H38 ballast.