Ceramic Metal Halide (CMH)

[Guest]

One last safty check if you dont mind simba. Wiering is the same as before outside of the fact I did the wirenuts correctly now Also I added a ground to the oil cap.

The black thing in the back still needs to be screwed in the cylinder is attached to where the flag would go, yes this is a mailbox (7$ and roomy!)

I want to note that I have NO GROUND attached to the reflector, thats okay right?

Also the oil cap has rubber surrounding itself and taped on w/ electric tape but otherwise it is free standing is that okay or should I secure it simmilar to the cylinder (starter?)

Final question, out of curiositys sake say those things do touch is it just letting out a huge charge of electricity then going back to normal or are we talkin a real explosion w/ shrapnel and stuff?


Thanks!

 

[jdubz206]

I will say firstly, that i think the CMH bulb is the best veg bulb hands down, but I think there would be better buds, and less leaf material if an hps was used in flower in place of the CMH. I would use the CMH through veg, the first two weeks of flower, switch to hps, then switch back to CMH the last two weeks.

I used the CMH all the way through flower and it works fine but there is a lotta leaf in the bud but I noticed it more in my bagseed plants than i did my grape ape so it could be strain dependant. But it should definatly be used even over MH for veg.

Thats just my noob opinion after using it all the way through only once.

I think under ideal circumstances I would use all the way through , 2 400w hps and 1 cmh in the middle... would be the perfect balance.

i agree completely...i'm going to do a run of veg with t5's and another with a 400 watt mh just to see the difference. i am going to post some pictures in a few days of seedlings that were vegged directly under a CMH and others that were vegged directly under 4' 6500k daylight t8's. The leaves are bigger with the CMH and have stretched more but the amount of nodes and growth is almost exactly the same. i'm swapping up my flower room to all super HPS - 2 600's and 2 400's. just waiting for summer to end...

 

[FreezerBoy]

I'm more interested in the heat it kicks, and how close plants can get to it before one sees burn.

I cool my 250CMH with a 76 cfm axial fan. It can hang within 2"-3" of the canopy.

 

[NorCalFor20]

i agree completely...i'm going to do a run of veg with t5's and another with a 400 watt mh just to see the difference. i am going to post some pictures in a few days of seedlings that were vegged directly under a CMH and others that were vegged directly under 4' 6500k daylight t8's. The leaves are bigger with the CMH and have stretched more but the amount of nodes and growth is almost exactly the same. i'm swapping up my flower room to all super HPS - 2 600's and 2 400's. just waiting for summer to end...

Yeah my post wasn't to discourage anyone from getting a CMH bulb, in fact I think everyone should use it for veg, first 2, and last 2 weeks of flower.

I am looking forward to higher wattage CMH's being released, so that I can run 1k's. My dream grow would be 2 1k CMH bulbs during veg and swapping to HPS for most of the flowering beside the first 2 and last 2 weeks like i said.

The CMH produces an incredible amount of resin early in flowering,but leaves me wanting switch to HPS in the middle of flowering to prevent excessive "buds leafs" that I have seen from the CMH.

Awsome bulb simba, the CMH is hand down best veg bulb IMO I wanted to clarify that before anyone said I was hating on the CMH because I love it for veg. It's way better than any MH conversion bulb ive seen, so I'll keep re-lamping with CMH for vegging until I can harness the power of the sun!!!

 

[sam303]

Can CMH bulbs cause HPS ballasts to fail? Will a 400w CMH bulb work in a Sun System 1 (SS-1) 400w HPS ballast from sunlight supply? Can you enclose a CMH bulb with tempered glass like you can with an HPS? Thanks,

 

[sam303]

I ran the CMH 400w bulb in my Sun System 1 fixture for 3 days.. and it goes out.. causing a brownout throught the house for half a second. I try putting the HPS bulb back in the fixture and firing it up.. everything seems ok but then 20 minutes later the power goes throughout the house for 1/2 second. I try the CMH bulb again 20 minutes later and it works for about 20 minutes.. then brownout. What could be the problem here? The ballast and hps bulb worked fine for 8 months until I put in the CMH bulb.. now problems. That's why I ask did the CMH bulb damage my ballast?

 

[hoosierdaddy]

After about 40 days of flowering with my new 400wCMH, I too am seeing some excess in sugar leaf on the buds. But here's the thing...I am not sure that the mass of the bud would be any greater with the HPS. Seems to me that the buds are probably going to be just a big as with the HPS, but with the addition of the sugar leaf growth from the CMH I think the buds now do indeed have a greater mass than they would..if you count the sugar leaves as part of the bud. And I do count them, because these sugar leaves are as triched up and greasy as they can be on all my plants. Accept for the Thunk, but sativas are funny animals and you can't judge their worth by the looks of the resin.

Theory states it should be better, and I am not one to go against what is.
And even though the growth pattern may be different than with straight HPS, I can't say it isn't better. It sure looks fine to me.
I must add that I do have an additional 150w HPS burning too, but it is only throwing good light at the bottom of the plants and the top colas do not see much of it at all.

 

[simba]

Bonsi, Ya the CMHs work great in Super suns. Id say get the SS1

to the side by sides.. we all know i cant post good pics but thats why i switched seing for myself.many moons ago..

Haze, nopes you should get these two..
70 Watt Metal Halide (M98)
70 Watt MH Ballast Kit (M98)
(Core, Capacitor, Ignitor Included)
~ Part # M0070-71C-511 ~
and
Protected
70 Watt 4,000 Kelvin
MHC70/U/MP/4K/ALTO
$46.00 USD

ask for a medium socket they may throw one in just for kicks..

Jawn, ya that size go with 250.. keep them at least 3" away and ur golden..
150 will be under kill unless 2 150s but stick with 250..

charles. that looks good if you can mount the cap to the side wall..
ALso get a sheet of concrete bored (small section avail at Home depot) or 12x12 ceramic tile.. and have that under the mail box as an insulator..
ya if that cap shorts it could be just a nice pop or if it arcs and welds it self shorting could be bad.
get a Good Surge protector with a breaker or a GFCI 12 bucks from Homedepot. that way if any elec touchs the mail box it will consider it a ground fault and kill power faster than a fuse could..
if u put a POS computer fan in that mailbox and close the door.. (obv have vents on other side of fan (lenght wise) you can keep that cool ish..

FB, as allways lookin Good.

no cal and others adv tech is actully waiting on lower wattage but being Higher effeciancy over 600 watt CMHS (thats all i can say) for now..

sam, NO.. something else is wrong.. I have never heard of that..
if your getting a brown out after 20 minutes id say the Core is shorting out once it gets to temp Warranty that ballast out..
and warranty the cmh.. tell them the truth.. and they will help you.. (they test all bulb that come back so they will know)

hooser, ya its a bit dif.. but i so love the results..

 

[haze12421]

Simba I Also Have a mh 70 watt ballast from econolight. Would it be ok to use that? If not please explain why. I dont want to throw away 40 dollars for nothing. Thanx a lot. Was hoping to use the 70 watt cmh light in my pc tower and use it as a mother clone chamber. Right now with a 70 watt hps its to hot in there

 

[simba]

Haze, ya if you have a 70 mh unit use that..(i didn't know you had the mh already)
just do me a fav and open it up it should have a label on the reflector if not pop it off look for the label on the ballast.. it should say M98
most mh 150 watt and under are Metal halide Pulse start some 150s are probe (not allot but there out there) and 175 and up are probe start..
(should be all 10-150 MH are pulse start but if i say all someone will find a dif kind magically LOL) and thats stayin out of the reactor type.. IE CWA, HX etc lol..

 

[jawnroot]

NorCalFor20: I just checked out your grow log. I don't mean this to be antagonistic, so please don't take it that way, but based upon the continual stresses that were present, you cannot point the finger at CMH.

At any given time during the grow, your plants were either water stressed, nute stressed, temp stressed, root bound, or all four simultaneously. Plus, the bagseed you grew were of unknown lineage. The leafing you saw may very well have been a trait of the strain.

Don't get me wrong, I'm not saying your grow was terrible, because it wasn't. However, it was no where near refined enough to say, hands down, that the CMH was the cause of your leafy buds.

The bottom line? CMH is a newish technology, and hasn't 100% proven itself in the grow arena. Before we make sweeping generalizations, more tests need to be run.

I know that for me personally, with the space I have to work with, a CMH is ideal because it doesn't kick the heat of an HPS. This isn't to say it's the perfect solution for every grower, but for me it definitely fits the bill. Based upon some of the pics I've seen in this tread, I think it will serve its purpose quite well.

 

[hoosierdaddy]

jawnroot, you need to be aware that even though the CMH does indeed create less heat than a comparable HPS, it isn't a significant difference. If you can't keep a 250 HPS cool you won't keep the 250 CMH cool either.
They both get hot as heck in a small grow, and you will need to design accordingly.

I have both a 400CMH and a 150HPS in a tube within a 1 sq mt floor space. I have some serious cooling and air moving going on to be able to accomplish that.

 

[Guest]

just out of curiosity how hot are we talking, I have the mailbox attached to some wood, its not going to ignight right?

 

[jawnroot]

hoosierdaddy: I could run a 250 HPS in my space if I so desired. However, the spectrum advantage was really the winning ticket for me, as I just wanted one start to finish lamp. The difference in heat output, however minimal, is also a plus.

I've learned the significance of ventilation. I'm going to be running a proper inline fan, with a CFM rating that will exchange the air in the box once every five seconds. This, coupled with the box being in an A/Ced room that can go as low as 60*F, should solve any heat issues.

We'll see, though. I always do a dry run ahead of time, with just the equipment running, to verify that I'm where I should be temp wise. If the 250 proves to be too much, I can always downgrade.

 

[hoosierdaddy]

I wouldn't downgrade. I would increase the integrity of my air moving equipment to make it work.

 

[Guest]

Hey my house isnt on fire!
Thanks everyone esp simba on the electrical side.




I dont know if its normal but my digital camera pulses and stuff and the color changes around in a weird way, the light visibly is just bright white tho.

And for those keeping score yes my hood and balasts are both mailboxes

 

[hoosierdaddy]

Charles, I think the mailbox thing is simply brilliant. What better ballast box for the money?
Good job.

 

[inefectualize]

does anyone know if a 250 watt magnetic ballast for hqi mh will run a 250 cmh?

ansi code M80 like this one

http://www.hellolights.com/index.asp?PageAction=VIEWPROD&ProdID=165

 

[Guest]

Thanks Hoosier, I was inspired by the DIY reflector mailbox. Honestly I can see myself using mailboxes for a fewthings.. which is kinda zaniy

 

[Pharma Geddon]

This might be the wrong place to ask but it does relate to giving the cmh a fair test.

How much yield variation is there in a (pretty stable) seed grow?

I have heard that yields can vary 15% just because... even though the previous grow was as identical as the grower could get it.

I did start a side by side test vegging with a Grolux 600w and a SunMaster 600w mh 7200K. They started off with the hps looking slightly better but then the mh plants looked healthier. To my mind some work would need to be done to make sure that the nute regime suited the bulb, or all the results would show is which bulb suits your feeding schedule the best.

Any ideas on how consistent I can get the yields? (cmh for veg at the moment.)