Capt. Kush
Member
Can any magnetic ballast be used for a cmh bulb?
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IndoorScore
Member
Can anyone tell me if the vertical bulb setup is more or less effective than horizontal for this type of bulb?
Trying to find the cheapest 315 fixture but want to make sure the orientation won't make much of a difference.
Thanks and my apologies I'm sure it's in here somewhere but I couldn't find it.
Trying to find the cheapest 315 fixture but want to make sure the orientation won't make much of a difference.
Thanks and my apologies I'm sure it's in here somewhere but I couldn't find it.
Phillps CMH are designed as power saving replacement lamps in conventional magnetic ballast luminaires in commercial applications. 1000/860 400/330 250/205 175/145
Their CDM line is a new departure & generally incompatible w/ mag ballasts. That's the 315, 210 & some smaller lamps.
GE makes a 400w CMH conversion lamp for 400w HPS ballasts.
There's this oddball marriage of a 210w CDM & a mag ballast-
http://www.metalhalideshop.com/3881...tore=mhs_eng&gclid=CPaQmorXisICFQGoaQodchoAvg
Probably doesn't have quite the efficiency of the same lamp on a Philips electronic ballast but the price is right for DIY in truly small grows.
I figure it doesn't matter much if at all. Vertical reflectors are generally taller. It can be an issue w/ low ceilings.
Qqqqqqqqqqqqq
New member
Still not sure about these. Can anyone provide a solid side by side with a 1000w hps containing yield results? I keep looking around and anything I've found comes up empty in the end.
IndoorScore
Member
I wouldn't put a 315 against a 1000hps. Wouldn't put much against it.
630 is going to get you closer but realistically, in terms of heat and coverage and power draw, 630+315 would murder a 1000W IMO
630 is going to get you closer but realistically, in terms of heat and coverage and power draw, 630+315 would murder a 1000W IMO
Vertical reflectors will tend to be more intense for a given amount of wattage, but the footprint tends to be less. Look at some of the PPFD readings for reflectors like the OG. Growershouse did a writeup where they got as much PPFD out of a 400 watt bulb in an OG as a 1000 watt in a horizontal reflector, but the footprint is small.
There was a guy here that made a post comparing the cycloptics to the phantom using 315 CMH. IIRC PPFD in both was well over 700 in a 3 x 3, which is really really good for such low wattage.
I've wondered myself if a lot of the success of the CMHs isn't because of the style of reflectors they use which gives more PPFD in a small area. To know for sure you'd need to compare the different lights using identical reflectors.
Uniformity of average PPFD is just as important as spectrum to maximizing plant growth. From my experience the best uniformity is delivered by Cycloptics vertical reflector. I didn't have to move the plants around or raise and lower the reflectors.
I have been in learning mode re: CMH bulbs / ballasts, etc. Because I grow in a small tent, I haven't seriously consider the readily available 315W systems, mostly because of the overhead room.
I almost bought a CMH ballast kit for a light fixture and made my own in a switch box, but a former grower gave me his 400W Sunleaves ballast, which is switchable from HPS to Metal Halide.
This is a BIG old school magnetic ballast. Based on what I've read, I believe I can power either a 250W Philips Ceramic Metal Halide MasterColor bulb with this, or go bigger if I expand the space.
Am I right about being able to use this ballast on the MH setting to power a CMH?
How about going with a smaller wattage bulb? I believe it will just run a bit hotter but don't know for sure.
Thanks!
I almost bought a CMH ballast kit for a light fixture and made my own in a switch box, but a former grower gave me his 400W Sunleaves ballast, which is switchable from HPS to Metal Halide.
This is a BIG old school magnetic ballast. Based on what I've read, I believe I can power either a 250W Philips Ceramic Metal Halide MasterColor bulb with this, or go bigger if I expand the space.
Am I right about being able to use this ballast on the MH setting to power a CMH?
How about going with a smaller wattage bulb? I believe it will just run a bit hotter but don't know for sure.
Thanks!
This is the CMH lamp you want for that ballast-
http://www.usa.lighting.philips.com...h-allstart-technology/928601165903_NA/product
They were developed as screw in power saving replacements for 400w MH lamps. I have one that I use for veggie starts & occasional seedlings.
It's not a good idea to mismatch lamps & ballasts. I advise against using a 250w lamp on your 400w ballast.
I have a question for you smart folks. I am new to the 315's, I just started using a 315W along with a SS400 LED. Am just using it to finish this grow then on to the next project.
I would like to do a 5 plant stacked vertical screen grow with the 315 as the top bulb and a 315 as the lower bulb. I am in a 4x4 tent with plenty of ventilation, and AC if needed. I will be able to move the plants from 16" to 22" from the lights. I have grown vert before only with a 400W HPS.
I have noticed that with the 315W ballast outside the tent, that although the lamp is warm I can get the plants within 16" from the light with this this horizontal grow in progress. I really like the response from the plants with the addition of the to my grow.
My question is this going to be too much heat for my tent?
GR
I would like to do a 5 plant stacked vertical screen grow with the 315 as the top bulb and a 315 as the lower bulb. I am in a 4x4 tent with plenty of ventilation, and AC if needed. I will be able to move the plants from 16" to 22" from the lights. I have grown vert before only with a 400W HPS.
I have noticed that with the 315W ballast outside the tent, that although the lamp is warm I can get the plants within 16" from the light with this this horizontal grow in progress. I really like the response from the plants with the addition of the to my grow.
My question is this going to be too much heat for my tent?
GR
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JRontheEastcoas
New member
Ive got a question for anyone running the phantom 315cmh, what timers do you use? I upgraded from the older magnetic ballasts to a few new digital ballasts (both cmh and reg mh/hps) and have been going through timers left and right. What are you guys using?
You'll do fine with enough air exchange thru the tent. Put it together & dial it in before introducing plants.
860watt cmh why not horizontal
860watt cmh why not horizontal
How come these lights can't be positioned horizontal? My guess is the arc tube will get hot and bend and touch the sides but I'm just guessing.
I need new bulbs for my 1000hps and I don't do the vertical/stadium thing-sure wish I could run them horizontally.
Thanks.
AA
860watt cmh why not horizontal
How come these lights can't be positioned horizontal? My guess is the arc tube will get hot and bend and touch the sides but I'm just guessing.
I need new bulbs for my 1000hps and I don't do the vertical/stadium thing-sure wish I could run them horizontally.
Thanks.
AA
I ran two 315's in a 4X4 tent, it's a perfect fit, the heat is no problem, 6" fan is fine. Horizontal worked for me.
There are a fair # of other MH lamps that are vert, base up or hor mounting only. They kinda explain it here-
https://www.1000bulbs.com/pdf/venture-ps-mh-brochure.pdf
