need help with a metal halide issue please

hey guys thanks in advance for any help or tips. okay so i have two separate grow tents. a 1k hps for flowering and ive always vegged under an 8 bulb T5.

I'm always trying to improve so i picked up a 400 watt switchable ballast with an air cooled hood.

I used the 400watt hps for a few days before i got a new mh bulb. the hps worked perfect but i wanted more of a veg bulb.

when i got the new 400mh it was bright for about 5 seconds then went dim about 1/3 of how bright it should be. so i tried a new bulb same thing..

so basically the hps portion of the ballast works perfect but the metal halide does not.

which seems odd to me. I'm thinking something failed in the ballast.. is there any pieces that the metal halide uses that the hps doesn't?

any help or prior experiences will be highly appreciated since Id preferred to fix it rather than buy a new one

What ballast are you using? The one you have may be bad, too. What about 250w CFL(s) with reflecors for veg? Is there a "high/low" type of setting?

that is weird. like Numsi asked; what type of ballast is it?

its not a high end ballast i think its magnetic.. no its not dimmable it just has the mh/hps switch.. i have the ballast apart i mean i could replace the ignitor or the capacitor but why would the hps work with a failed part?

hps and mh bulbs are fired differently. i'd send the ballast back and get a new one. i don't know much about magnetic ballasts.

I know, stupid question, but you are letting the MH warm up for a few minutes after it's on, right? Was it a used ballast? Damn you Craigslist!!!!!!!!!!!!

This is why I buy Lumatek's.

What brand of ballast and mh bulb?

http://www.progressivegardens.com/Sun-System-2-complete-400w-system-prod.html

this is the system i have. yeah i let 3 seperate bulbs warm up for 25 minutes all the same thing, gets bright for about 10 seconds than dimms very low.

could it possibly be a weak/failing part inside the ballast that can no longer support the metal halide operation but can still light up the hps?

cap could be going bad it might not affect the HPS as much. or the switch that would normally turn off the igniter in the circuit(the part needed to make a ballast light HPS) could be bad causeing issues.

Yea , I'm thinking the same thing, like a wiring issue.

okay so you think the igniter is staying on the whole time causing the issue with the mh bulb.

what type of switch would I be looking for like a relay, a transistor maybe? does the mh use the igniter also to turn on?

thanks for the help

what bulb are you using? is it a retro fit mh bulb? if that is the case maybe it needs to be run in hps mode? try and find that out

pics help, but it should be an analog switch. the probe start MH does not use the ignitor to turn on, a malfunctioning ignitor will still usually light a HPS bulb but if left on (bad switch in addition, this is why its not recommended to run MH on HPS, in case the ignitor is faulty it will fuck up you MH bulbs. otherwise if ignitor is fine it should be no problem to run an mh bulb on an hps ballast without a switch.)

what you need to do after thinking about this, is at the minimum, replace the switch(analog switch), i would also replace the ignitor as it is probably faulty too. i would say the cap. is fine though after thinking about it a bit.

2easy said:

what bulb are you using? is it a retro fit mh bulb? if that is the case maybe it needs to be run in hps mode? try and find that out

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wouldnt matter conversion bulbs will run in MH ballast just fine.

polyarcturus said:

wouldnt matter conversion bulbs will run in MH ballast just fine.

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ah ok cool good to know. i was just throwing suggestions around.

2easy said:

ah ok cool good to know. i was just throwing suggestions around.

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yeah they are just rgular MH with a slight design difference to handle the current from the ignitor, they are actually less efficient than regular MH. i use regular MH in my HPS ballast the life loss is not as much as people like to make it seem it will work just fine.

http://www.htgsupply.com/Product-AgroMax- 400w-Metal-Halide---6500K-Ultra-Blue-Daylight-Spectrum-Bulb.asp This is the bulb

there is two switches on the ballast an on/off switch and a hps/mh switch. is the igniter switch the hps/mh? because i see no other switch on the inside,

so if the mh doesnt need the igniter should i just remove it from the circiut and see if it works? before that im going to try the bulb with the ballast on hps

i will post pics of the ballast and how the light works tomorrow

I wouldn't look too far into it,my mh bulb did the same thing it got a lil dimmer than usual but that's because i was testing my ballast for the first time and instead of waiting 15 minutes+ to turn it back on i just tried to switch it on which in turn made the ballast fan run but the light didn't come back on and the ballast was slightly louder than it should be.So if you turned your ballast off and tried to turn it back on then thats prob the issue.MH tends to burn out a lil quicker and ignite slower.Most likely the next bulb will do the same.Many people don't even notice the difference in the brightness.

yeah the first time i was in a rush so i put the bulb in and switched it while the ballast was still hot.. then i realized what i had done so i tried it again this time i had the ballast off all night and it was the same.. I have to post pics tomorrow it is very dim like incandescent light bulb dim.

I figured that was the problem.Home depot sell bulbs 20-30$ (cheaper than online).I did the same but it still worked noticeably well.even though it runs hot as hell