MH bulb woking with my HPS ballast?

Alright so I picked up a free light from a busted grow-op (lucky me)

The hood is a Hydrofarm RD Luminaire

The Ballast says 400W HPS and is built into the hood.

Now I figured it was a HPS because of what the ballast said, but when I turned it on I noticed that the light was very blue, and didnt look like an HPS at all.

I looked at the bulb, which read "Sunmaster 400W H37 WDX"

I went to sunmasters website and looked it up, and the website said that the bulb was a "Warm Deluxe MH bulb"

Now I dont have that much expierience with HPS or MH systems, but i thought you couldnt mix and match the bulbs?

Is this perhaps a conversion bulb? Or do MH bulbs work with Hps ballasts? Mabey my ballast is wrong? Hell, mabey it is a HPS bulb and im just an idiot.


What do you guys think? Ill post pics 2moro if you find it necessary.





Thanks, Jobo

i know that a lot of ballasts have the option to switch between mh and hps. sun system makes these ballasts.

rubancinta said:

i know that a lot of ballasts have the option to switch between mh and hps. sun system makes these ballasts.

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Do they switch automatically? Because mine just says 400W HPS. Im not sure which brand it is, it just came attached to my hood.

If theres no switch on the ballast then its a conversion bulb. You can buy MH conversion bulbs for HPS ballasts.

My electronic ballasts don't have a switch for HPS or MH, they're automatic,
but I suspect you have a MH conersion bulb, but maybe it just runs on the HPS ballast,
although they aren't supposed to as the bulb description says for use in MH ballasts only.

HPS ballasts are capable of running an MH bulb if you disable the ignitor as the MH doesnt need it to fire. My switchable (magnetic) MH/HPS ballast has a switch to turn on the ignitor for the HPS.

It is possible someone has modified an HPS ballast as they are much more common. Its just a possibility, you should try running an HPS bulb in the ballast and see if it works. I still think it would be a conversion bulb tho.

I put Both my Hps and MH ballast in one Box, and ran the wire out to the lights.

I stoped smoked a blunt, then went back to finish.

Little did I know I switch the wire, so from the MH ballast, it went to the HPS bulb, and the HPS balast went to the MH bulb....

When I powered it on, the HPS came on no problem, But the MH lit up a little, but not all the way.

What was weird, was the HPS turned on with the MH basllast, and the MH wouldn't turn on with the hps ballast.

Now logically thinking The hps should not have worked without the Ignitor correct?

So I got no good input here, My logic is fucked.

seejay said:

i put both my hps and mh ballast in one box, and ran the wire out to the lights.

I stoped smoked a blunt, then went back to finish.

Little did i know i switch the wire, so from the mh ballast, it went to the hps bulb, and the hps balast went to the mh bulb....

When i powered it on, the hps came on no problem, but the mh lit up a little, but not all the way.

What was weird, was the hps turned on with the mh basllast, and the mh wouldn't turn on with the hps ballast.

Now logically thinking the hps should not have worked without the ignitor correct?

So i got no good input here, my logic is fucked.

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i have been saying this for some time now, and many here on the site say no. Well i'm glad to see someone had the gonades to try it. Whats funny is that many willsaythat the bulb will blow up. Did yours, mine don't. Lol

mygirls said:

i have been saying this for some time now, and many here on the site say no. Well i'm glad to see someone had the gonades to try it. Whats funny is that many willsaythat the bulb will blow up. Did yours, mine don't. Lol

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I wouldnt say "will blow up" But it DEFINITELY Can. The ignitor is putting a lot of unnecessary stress trying to fire a bulb that doesnt need to be fired, it only needs electricity applied.

It will cause the MH bulb to break down Much faster.