Running MH bulbs in magnetic HPS ballasts

[deepforest]

some trusted individual told me theres no need for conversion bulbs or MH specific ballasts if you want to run MH and all you have is HPS core and coil ballasts. they said , for the 1k at least, that its perfectly safe, you just lose bulb life over the long run burning an MH in HPS ballast...

is this going to burn my house down? the guy who told me is someone i trust but i favour safety first so i thought id ask here.

 

[oz.e.bob]

The colour output from the MH globe will be slightly warmer (lean towards the red end of the colour spectrum) it will loose a little bit of intensity and it will indeed have a shorter life but otherwise will work just fine.

 

[apartmentblower]

The colour output from the MH globe will be slightly warmer (lean towards the red end of the colour spectrum) it will loose a little bit of intensity and it will indeed have a shorter life but otherwise will work just fine.

good to hear

MH bulbs are cheap anyways , cheaper than running conversion


second q... are old magnetic ballasts dangerous? i bought them used off some stranger. they are basic HPS ballasts unboxed , i think you call it pigtail style. im boxing them up but they look pretty beat up, some even look like they have a bit of rust on them. but people say mags last forever, so whats the deal. i havent fired any of them up yet.

 

[~fvk~]

What? You can turn an HPS ballast into a switchable by bypassing the ignitor, but I'm almost positive you don't want to run mismatched bulbs with mismatched ballasts. Wait for some more replies, not saying that OZ doesn't know their shit, but just to be on the safe side... Yeah.

 

[NorCalFor20]

if you remove the ignitor you SHOULD be ok (not UL listed/CERT), better off just getting a new ballast though.... its risky

 

[masterKahn]

if you remove the ignitor you SHOULD be ok (not UL listed/CERT), better off just getting a new ballast though.... its risky

Swichtable ballasts due just this i think. The switch bypasses the ignitor. If you look at a MH ballast next to HPS ballast and they are the same except the MH lacks the ignitor. But it could be risky.

 

[EvilTwin]

DF,
I don't for a moment believe that running a MH on HPS ballast will change the light spectrum. Someone's been smoking too many funny cigarettes.

Here's a shot of a 400 MH bulb running on a 400 hps ballast minus the igniter. Looks pretty blue to me.

It is my understanding that switchable MH/HPS ballasts merely remove the igniter from the circuit. That would be the tap wire if it's an old ballast.
Peace,
ET

 

[In Vino Veritas]

good info.

 

[SpacedCWBY]

I bought a couple 400w mh's that came in a normal tube, like a hps bulb - not blown out. Haven't tried them on my hps c/c ballasts though. Got them off alibaba from the china folks for like $3 each or something. The hps bulbs I bought from them are still going strong though.

 

[oz.e.bob]

DF,
I don't for a moment believe that running a MH on HPS ballast will change the light spectrum. Someone's been smoking too many funny cigarettes.

Here's a shot of a 400 MH bulb running on a 400 hps ballast minus the igniter. Looks pretty blue to me.

It is my understanding that switchable MH/HPS ballasts merely remove the igniter from the circuit. That would be the tap wire if it's an old ballast.
Peace,
ET

I will forgive you for being a smart ass this time.
The reason that the light spectrum changes is that a hps bulb has an opearting voltage of 105-110v and a metal halides is around 130 with their respective ballasts tuned to match. This causes the discharge tube inside of the globe to run with lower exitation of the gas molecules and therefore with an altered colour spectrum, usually shifted to the warmer end of the lighting spectrum and with slightly lower intensity.
The ignitor is in the circuit for hps lights because they require a high voltage and with some types of ignitor a high frequency pulse to 'ignite' the discharge tube. There are some metal halides that require this too.
There are also some types of globes that have an internal ignitor (actually inside of the tube) instead of one in the control gear (ballast box) also.
'Ideally' you should always run matched globes and ballasts.
But, without looking at your equipment, if you retro-fit your halide into the light fitting, without touching the ballasts wiring, it will most likely fire into life, with the minor short comings that I have mentioned.
Digital solid state ballasts are a different proposition all together and are generally made to run a particular type of globe and wattage, although some are switchable, they do not have the flexability of reactor type control gear.
There is no problem using second hand control gear either. The analogy would be like buying a second hand car. It may fail sooner it may not, still works the same.
Any more questions?

 

[~fvk~]

If you feel that you can comfortably mess with a ballast's wiring, try doing this... It's not too complicated, just don't burn your place down.

http://www.icmag.com/ic/showthread.php?t=41132

 

[deepforest]

I will forgive you for being a smart ass this time.
The reason that the light spectrum changes is that a hps bulb has an opearting voltage of 105-110v and a metal halides is around 130 with their respective ballasts tuned to match. This causes the discharge tube inside of the globe to run with lower exitation of the gas molecules and therefore with an altered colour spectrum, usually shifted to the warmer end of the lighting spectrum and with slightly lower intensity.
The ignitor is in the circuit for hps lights because they require a high voltage and with some types of ignitor a high frequency pulse to 'ignite' the discharge tube. There are some metal halides that require this too.
There are also some types of globes that have an internal ignitor (actually inside of the tube) instead of one in the control gear (ballast box) also.
'Ideally' you should always run matched globes and ballasts.
But, without looking at your equipment, if you retro-fit your halide into the light fitting, without touching the ballasts wiring, it will most likely fire into life, with the minor short comings that I have mentioned.
Digital solid state ballasts are a different proposition all together and are generally made to run a particular type of globe and wattage, although some are switchable, they do not have the flexability of reactor type control gear.
There is no problem using second hand control gear either. The analogy would be like buying a second hand car. It may fail sooner it may not, still works the same.
Any more questions?

awesome thanks!!!! i got a MH 1000w burning in my HPS 1000w ballast as we speak. didnt take the ignitor out of the circuit or anything like that, just plopped the bulb in and it fired up.

i mean its obvious that there is probably a safety issue greater than if i had just run a conversion bulb, but i see so many growers doing this and the guys that told me its fine know their shit. as well, ive read around on some forums that a few other people are running MH bulbs in HPS ballasts, without removing the ignitor from the circuit as well.

 

[redheadfreakin]

Sweet!
Great info oz!