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Ceramic Metal Halide (CMH)

MPL

Member
Some basic info:

Ceramic Metal Halide lamps are currently not available in sizes over 400 watts. Philips is working on it, however there is no ETA.

The CMH lamps 150w and lower should work with digital ballasts.

250w and 400w CMH lamps will NOT work with ANY digital ballast EXCEPT the ones SPECIFICALLY made to fire CMH lamps.

250w and 400w CMH lamps will work with most good quality 250w (ANSI S50) and 400w (ANSI S51) HPS ballasts.

Read the second post in this thread.

This is the spectrum for a CMH bulb:

cdmspd.jpg



Azeotrope said:
Folks, I just recieved a very good and insightful PM in regards to "trouble" some folks are having with these lamps. It is not the lamp (99% of the time). These lamps were designed as a retrofit for industrial lighting fixtures that have a standard 3' ignitor. this means the ignitor was designed to strike/start a HPS (easy to start) up to 3' of wire away from the ignitor. Most of the off of the shelf Hydro shop ballasts are using just that and getting away with it. The less expensive ballasts use cheap components and switchables should be outlawed in my view. As the switchables go, they put a switch in the ignitor circuit. Most of those switches are not 5kv pulse rated or even 600v rated as they should be at a minimum. If you are going to use these bulbs you need to understand that they require (for best reliability) a high quality ballast kit (that will generally provide a high quality ignitor) ie. Advance, Venture, Sylvania, Sola(o.k.) and such with high quality STRANDED 600v rated 16ga - 14ga wire between the ignitor (ballast box) and the socket. You should also use 5kv pulse rated connectors and always ground your hood/reflector (safety). The only time in what is now many years of using these that I have had one fail, it was like 3 or 4yrs old and toasted by over use.

The HPS bulbs are easy to start and the CMH bulbs are harder to start. A weak or old ignitor, core or capacitor can be troublesome. Keep your cords to 6-8' if all the above is in order you should not have trouble. I love them so much I just bought 2 new 400w horiz at my supplier today for a re-lamp. $79.00 US! Can't beat that!!!

Good luck and keep after it.

-----------------------

The original first post follows:



Ok, so I have been reading around and found a few posts about these bulbs. I asked some questions but decided I really didn't want to hijack someone else's thread. Besides, I don't think CMH bulbs have a dedicated thread yet anyway.

So, I have found out that the Philips CMH bulbs have better spectrums than any other HID bulb on the market. I also learned a lot about lumens, PAR etc.

Everything sounds great so far, except I have no idea which ballast to use to fire the 250w and 400w CMH bulbs. Can anyone recommend a specific brand?

Also, the CMH bulbs are supposed to have strong UVB output. Does using an aircooled hood with glass in place reduce/remove this UVB? Is supplemental UV lighting recommended in this case? Would the Hydrotek Silverstar hood work well with the 400w? Any recommendations on a hood for this bulb?

How hot are the CMH bulbs? In a small grow, would the 400w require an aircooled hood to keep it close to the plants? I wanted to use it in a space about 2'x2'x5'H... maybe a bit larger, but not by much.

Sorry for the noob questions, but I'm getting my first grow planned out and just want to be sure I'm getting the most for my money, as I am far from rich.

Thanks!
 
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simba

Sleeping Dragon
*Update 02/22/2009:

:headbange
also has any noticed Great Pops by one of the Major National Garden Wholesalers
they have picked up the Philips CMH line of HPS Retro Whites..
I have to say for them to pick it up as "New" shows it Has True Demand from the Customers up...
Gotta Give it up to Philips CDM Series CMH no companies efforts did it rather CMH has Proven Itself World Wide.. :respect:

:dance: :headbange :woohoo:


_______

Philips Ceramic Metal Halide HPS-Retro White (CMH) (HPS> <CMH)
250 & 400 Watt Uses HPS Ballast, 20-150 watt on other pages
http://advancedtechlighting.com/cdmed18.htm
international / world wide shipping
How was CMH Invented.
its the Arc tube of HPS and the Gases of Metal halide Basically.. and it created something totally new..
theres a few reasons it hasn't come to our Market faster but thats great all the bugs are out..

CMH INFO
Philips Ceramic Metal Halide MasterColor is available in
20-400 watts
20-150 watt PCMH's run on Pulsed start Metal Halide Ballasts Only
250-400 are avail in PS MH or HPS retro..
(we chose HPS retro for many reasons for horti)
the 250 and 400 "HPS Retro White Ceramic Metal Halide" are specifically designed for use in HPS Magnetic Core Ballasts..
cmh bulbs will run on a electronic ballast only if that electronic ballasts Specifically says for use with Ceramic Bulb on the actual ballasts..
actually cmh like the low Freq of Mag core ballasts over High Freq Electronic ballasts.
there preferred range is 144-240Hz mag core ballasts is 60hz



Ceramic Metal Halide ( CMH ) competes and Whomps the EYE Hortilux Blue (MT400D/HOR/HTL - BLUE)
comparing the 400 horizontals.. as the vertical 400 and both vertical and horizontal 250 cmh has 20K hours 5k longer than 400 WOW!

.................................EYE-BLUE..........CMH
Ballast........................MH-Probe..........HPS (easy conversion for hps users)
Price .........................$90-100............50-70
Life............................12,000Hrs.........15,000Hrs
Initial Lumens...............29,000.............34,800
Mean Lumens ..............22,000.............29,600
Lumen maintenance.......64%................85%

Now when you take the last 4 lines and really look at that your actually getting Twice the lamp for half the cost..

not only do you get more initial and Mean lumen's a longer life and more usable life (IE 85%)
the CMH has higher Red to Blue ratio and thats what we WANT to promote better Flowering

CMH doesn't Throw Heat like MH or HPS especially MH
it just so happens the arc tube (from the HPS side of the lamp) Blocks and absorbs allot of that energy and instead of radiating it it holds it and releases almost all up.. * Ya cmh does still throw some heat but Nothing compared to Equal Wattage in MH or HPS..

The Philips Retro white is also open Fixture Rated the EYE Blue IS NOT>>
you need to follow those ratings on your lamps if it states Enclosed fixture you better use a fixture rated Enclosed.

now you say but neither have High lumen's like my HPS Extreme.
ya thats because if you notice the SPD on the HPS you will see they increse the Lumen rating by creating more Yellow Light But thats not what we want..
in short hps dumps about IMPHO 50% of its Total outputted energy where the plant cant absorb it. where as cmh when you compare its Whole output about 25% about wasted like HPS (that 50% and 25% is not fully wasted just 95% of it.. in that range)


all below information is direct from advancedtechlighting.com Web site

cdmhps.gif




cmhfactembd.gif


pcdms51sftsvddaywwords.gif



PHILIPS-CDM-942-SERIES-DIST.gif
 
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Aye man:wave:
Any way you slice it running a 400w in a dresser-size space is gonna be hot! Similar to my first grow, even w/ a 265cfm blower it was a pain to cool down. These CMH's seem to be developing quite a following, perhaps i sould stop bein so cheap and look into em.
 

MPL

Member
Ok, I can do a few dry runs without glass and see how it works. In that case I'll make a DIY hood first and see how it goes. The only thing is I gotta figure out how to get a carbon scrubber in there. If it is pulling through an open hood I'm not sure how I'd do it unless I set up an inline scrubber or have the exhaust fan pushing through the scrubber...

I want to go with a 400w specifically because I do intend to go bigger later down the road. I can go up to about a 28"x28" footprint, so I may do that just to get a bit more space to work with for heat purposes. Would a 400w give any better results in this small of a space compared to a 250?

As far as cooling goes, I keep my ambients no higher than 75F, usually around 69F-71F. I noticed a lot of people don't use the AC much but I have always used it and don't see how anyone can live in 85F heat in their home. I think this will help some with the cooling. How much cooler do the CMH bulbs tend to run?

Do the CMH bulbs that advanced tech lighting sells have the UV block?

I still haven't figured out which ballast to get for this bulb. Does anyone have a recommendation? I've done all my research into digital ballasts and really don't know a thing about mag and coil units. I don't want to get a ballast and have it not work properly with the bulb.

Thanks!
 

pontiac

Pass That S**t!
Veteran
Sinse we're all talking about Ceramic Metal Halides, why not brush up on Pulse Start Metal Halides? I heard they output intensities comparable to HPS's... :chin:
 

simba

Sleeping Dragon
there are Metal Halide pulse start CMH bulbs but I Dont like them for HOrti USE they require ENCLOSED FIXTURE and people forget that and get HURT>. has happend....

youll find u can go close to ur plants with cmh..
 

stupor

New member
I have been confused as to which ballasts to use also after reading previous threads on CMH. The link simba posted says "Optimized for Operation on HPS Ballasts". I have an old, 2005, Icecap electronic 250 metal halide ballast. It can run a HPS too, although maybe not as efficiently. Hopefully it will run a CMH. What do you think?
 
G

Guest

You use a HPS ballast that is the correct wattage. Standard core and coil ballast. ANSI S51 for 400w for example or any reguar HPS ballast that you would buy to run a horti. No digital worth chasing at this point as the cmh can't operate on the high frequency of lumatek types. The Icecap is a nice ballast, but not to be used with these bulbs!

I don't like glass as it does cut out some (alot actually) of the UV and far blue photons. I have two 6" cool tubes that I made a long time ago from custom ordered simax brocillite (sp?) glass that I no longer use. Best to control the air temp entering your area and ventilate well. Icecap curently offers a 150w made by Hatch Transformers that is tuned/designed specifically for the cmh 150w bulbs.

Best of luck and don't stress the set up.

Hey Pontiac - We are not concerned about "lumens" or output if the spectrum doesn't stack up. However, I do believe that venture makes a fairly full spectrum e-ballast or natural white bulb or something. Still not the same though from what I can tell.
 
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simba

Sleeping Dragon
after testing many ELEC ballasts in CMH catagory VS came up on top.. Adv tech sells them 20-150 watt, and looking at advance's versions.. as advance has 20-400 watt E-ballasts..

ya Venture lighting has a Full SPD HPS RETRO Lamp also.. it dont compete with philips CMH,
<<<<~~has allready looked and no go..
philips, eye, osram, GE, venture (few others) have a CMH but not what philips has..

as far as a case any metal box or even a DIY Sheetmetal Box.. Just make sure u give it airflow (lowers its overal temp)

yes MPL ur link on post 10 will work just fine..
 

Pirate138

the Revenant
Veteran
nice thread, ive been wanting to buy a CMH and will soon. i heard they give off alot less heat and you can get the light closer to your plants without burning them. when ordering a bulb, we usually use horizontal bulbs right in a normal hood?
 

gladysvjubb

Active member
Veteran
Has anyone actually flowered using CMH? I would just use it for 12/12 only. I've got my eye on one to purchase, just want to make sure it's ok to flower with.


 

chimei

Member
I just want to confirm a few things.

The Horizontal CMH 400 watt Philips bulb can be used in a non enclosed hood right? I have been using it that way for awhile and thought it was OK.

I thought I read that the odds of one of these CMH bulbs exploding compared to MH and HPS standard bulbs is decreased. (Something about the wire wrapped around the element in the middle?)

Which is worse when exploding? MH or HPS?

I keep reading that you should be able to get it closer to the plants. This is even when it is not enclosed? (Assuming you have good ventilation in the room and temps are decent)

This is my first run with CMH, still in Veg.

When I used to do MH then HPS for flower I always noticed I could get allot closer to the bulb with MH, HPS always tended to bleach or burn when I got as close as I did with MH.

I think one time I used strictly a MH for veg and flower I would be as close as 4-5" at times with the colas.

With HPS I always have to keep at least 12"+ or I would get bleaching and under developed bud sites because they were stressed. Those of you that have done complete cycles with CMH, in flowering in a non enclosed hood how close were you getting to your tops with your CMH bulb out of curiosity?

I have had a 400 watt Switchable ballast for years now. My 400 CMH Philips works great when I put the ballast on HPS and run the lamp, as long as you have a 400 Watt HPS ballast (or switchable one set to HPS) you can run one of these bulbs right? There are no other specifics the ballast needs to support? It's been running fine for awhile now, just want to make there is nothing I missed and I have a fire hazard.


Thanks!!
 
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G

Guest

I don't worry about arc tube explosion or failure as I believe it to be rare when the bulbs are running as prescribed by the manufacturer. Yes it is open fixture rated. Yes you can get closer but, every set-up differs some so watch and move the lights down in steps. I allways start a little high and then work down as every strain has different tolerances. I also move it and wait one day. I have some aggressive Jhonny Blaze and one of them has been into my PL midi reflector before burning.

This is a great bulb fore cloning folks. Perfect energy ballance for rooting.
 

MPL

Member
I was thinking about the PL Deep or Midi reflector. The deep seems like it would be best for my application, since I'm growing in a square. Are these reflectors pretty good? I have read nothing but positive reviews, but not many people seem to be using them. Also, the deep says it recommends a height above the plants of 24" to cover a 3'x3' area. Would it hurt to lower the light to gain intensity? I was hoping to keep it 12" or lower above the highest colas...
 
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simba

Sleeping Dragon
ya the failures are rare but do happen..

PL reflectors are Designed odd..
they height they say for 3x3 is what u need.. its a very controlled output...
you will have to play with it....
(while ur plants are babies Young flowering.. you can move them closer together if ur going to have a pl deep at 2.5 or less feet up..

but a PL deep at its prescribed Height will give you a better pattern/output than another reflector at a lower height in comparing the two... (if that makes sense) but ya it would be nice to be able to lower the hood and adjust the output.. (coming!! Ya!)
Think of PL reflectors as PAR FLood lamps (security flood lamp) with no wasted light on the walls
as you raise the flood off the ground the circle spot gets bigger.Same with PL DEEP>.
ya PL is not the most common for Hobie growers. as they prety much designed for use at higher Rated Heights for greenhouses so all they gota do is relamp and get good light spread/output..

ya
horizontal --

Vertical |

think if ur plants ever go horizontal u got MAJOR Problems LoL.. or Horizontal for Horizon

think of these like HPS popping, (just arc tube failing,or rupture but contained)
MH operates at higher arc tube pure so when it pops it Blows... (IE The BIG ROUND BULBS are rated Open fixture as they designed to hold that blast)
but cmh runs at the pressure of MH but with HPS arc tube (basicly) and that hps arc tube is stronger than typical MH glass arc tube.. and with the extra protection of the paper clip looking tie.. it all holds together may just crack into pieces but wont PLAT the outer wall..
 
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MPL

Member
So let me make sure I understand...

If I use a PL deep hood all I have to do to adjust its footprint is to raise or lower it... which is what I've been assuming all along. It looks like what I'm going to end up with so long as I don't get any negative feedback for it.

With a 400w CMH in a smallish cabinet, is aircooling required as it would be for a HPS? I plan on pulling around 200-300 cfm through the cabinet. My ambient temperature are around 70F.
 
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