Can a HPS ballast run a MH bulb?
- Thread starter stoned16
- Start date
Standard magnetic ballasts can't run a regular MH without modifying the ballast. Check out the CMH thread about conversion lamps for running on HPS ballasts. I believe that some of the electronic ballasts can run either, depending on the manufacturer and the wattage.
CMH thread - https://www.icmag.com/ic/showthread.php?t=72215
CMH thread - https://www.icmag.com/ic/showthread.php?t=72215
Nope MH = Metal Halide and CMH = Ceramic Metal Halide, totally different light spectrums.
jahrastafareye
Member
There is such a thing as a dimmable digital ballast that can run either mh or hps , such as the phantom.
Thanks but my original question is i have a sunmaster 250w mh light that says it runs off a hps ballast, do you think it will run off my 400w hps ballast?i got it off a guy who bought it in a grow shop so im presuming he talked to the shop owner and he gave him the interchangable bulb am i correct?
Unless it is one of the newage auto-detecting digital ballasts the wattage on both the ballast and the bulb need to match. "Convertable" ballast is the name for one that runs both and it has a toggle switch. Not sure about the digital stuff. I believe both HPS and the Ceramic Metal Halide (CMH) run off of a HPS ballast and a Metal Halide (MH) runs off of a MH ballast only.
tokinblackguy
Active member
Short answer, no it will work and you risk, shorting out the ballast, exploding the bulb, and worst of all FIRE. 250W bulb, never in different wattage ballast, MH, CMH, or HPS. Digital, I'm not sure but I would say "no" to that as well if I had to guess.
If your ballast were 250W HPS, I would tell you "yes, it can be done. Easy way would be to install a switch inline with the ignitor on your HPS ballast. You could also do similar with MH ballast if you wanted to make it HPS, by adding an ignitor and installing the switch. The switch is not necessary either way but makes it easier when switching back an forth from MH-HPS and HPS-MH.
Hope this helps and answers your question
sun Master or sun pulse???? sun pulse makes stuff like that...I run 2 600W pulse start MH bulbs in one 1000w hps ballast.. maybe a search of the ballast/bulb name??
the 250 and 400??? no clue
good luck
Thanks for all your answers guys, i don't think im gonna risk trying it out anyway 
wouldnt be the brightest idea probably blow up in my face!And dont think ill re wire the ballast either im not great with electronics and dnt want to burn the place down! Its just annoying me cos i have a niggly feeling it'll work because i was given them together and your man seemed to think it would work and the ballast that runs my 400w hps says 250w on it and runs the 400w hps fine!?and on the side of the sunmaster box for the mh it says 250watt conversion this lamp operates on an hps ballast!so i dont no!!thanks again for your comments great resource this place is! I spend way too much time here, but im always stoned so its ok im getting a grow underway at the moment just sorting everything out i've 2 grows under my belt already but that was kind of luck lol Hopefully you'll all be hearing more from me soon and ill get some pics up of the ladies. they've been enjoying life on our beautiful mother earth for the last 3 days Happy growing all
wouldnt be the brightest idea probably blow up in my face!And dont think ill re wire the ballast either im not great with electronics and dnt want to burn the place down! Its just annoying me cos i have a niggly feeling it'll work because i was given them together and your man seemed to think it would work and the ballast that runs my 400w hps says 250w on it and runs the 400w hps fine!?and on the side of the sunmaster box for the mh it says 250watt conversion this lamp operates on an hps ballast!so i dont no!!thanks again for your comments great resource this place is! I spend way too much time here, but im always stoned so its ok im getting a grow underway at the moment just sorting everything out i've 2 grows under my belt already but that was kind of luck lol Hopefully you'll all be hearing more from me soon and ill get some pics up of the ladies. they've been enjoying life on our beautiful mother earth for the last 3 days Happy growing all 
FWIW sunmaster HPS to MH conversion lamps are labeled with LM prefix but you still have to use the matching wattage bulb and ballast
If I understand you question. You have a digi hps ballast ??? If so Yes you can use a MH bulb. I use a MH to veg with then I switch to HPS to flower same Ballast..There are many Mag ballast that will do it as well. I'm using Lumatek...The ballast is a 600. I have a 400mh in it after it fires I turn it down to 250... Hope that helps ..
sodalitas
Member
Correct me if I'm wrong, but wasn't the OP's question 'Will a MH bulb spark in a HPS ballast?
Metal Halide bulbs have a BUILT IN ignitor, High Pressure Sodium bulbs do not.
HPS bulbs require a spark from the ballast, MG bulbs do not.
Yes, you can run a MH bulb in a HPS ballast.
No, you can NOT run a HPS bulb in a MH ballast.
Metal Halide bulbs have a BUILT IN ignitor, High Pressure Sodium bulbs do not.
HPS bulbs require a spark from the ballast, MG bulbs do not.
Yes, you can run a MH bulb in a HPS ballast.
No, you can NOT run a HPS bulb in a MH ballast.
1) This thread is 2 years old...so great bump.
2) When it comes to anything ekectrical,you best take Rives word as gospel.
thinkin
Member
Bump... cause just did a ton of research. finally satisfied with an answer.
Capacitors are different.
22mf for MH and 55 mf for HPS
No ignitor is necessary for MH
surprise surprise.. best answer was found icmag.com
here is the post that made everything clear
https://www.icmag.com/ic/showpost.php?p=1840024&postcount=12
Capacitors are different.
22mf for MH and 55 mf for HPS
No ignitor is necessary for MH
surprise surprise.. best answer was found icmag.com
here is the post that made everything clear
https://www.icmag.com/ic/showpost.php?p=1840024&postcount=12
D
Drek
I was going to mention that. Capacitance values are different for the bulbs (load). In order to run the bulbs with a high power factor (less heat), they have to run with a certain capacitance. Also, I believe the running voltages are slightly different meaning the secondary winding on the transformer (choke) are different. So, it's basically a different transformer, different capacitance needs, different ignition types, etc.
