Ceramic Metal Halide (CMH)

[non]

hi

there seems to be many interesting hps retrofit cdms (philips cdm-tt, osram powerball etc.)in the smaller end. but they all seem to be closed rated.

would aircooled closed reflector with glass be enough to hold the possible blast of failing lamp?

 

[the gnome]

Is this an appropriate wavelength for flowering?

Ive been running a 1000w sylvania 4000K Mh for 2yrs and recently the phillips 860w cdm.
they're killing it in bloom

 

[Seaf0ur]

I've run the 860 on a shitchable magnetic ballast, remember 860w CMH MUST be hung vertically, they perform well, seaf0ur also has been using one with good results on a switchable ballast...
good lite, but not alot of power savings... .just a better spectrum and different output for basically the same draw, still imo worth a try.



once again, imo worth a try

I think they are superior to HPS for a few reasons. First is the spectrum. It is more full and therefore your plant maintains vigor indoors longer. It is no secret that a mother plant should be brought outdoors into natural sunshine for a few months every few years to maintain full vigor. This is because HPS lacks much in terms of spectrum.
Second is rate of degradation. These CMH bulbs stay at a higher output longer whereas HPS bulb light intensity seems to fade much faster from what I noticed.
Lastly, color. It is just more comfortable to work under lights that aren't orange.

 

[Avinash.miles]

thanks for the input seaf0ur, hope u stay posted in this thread while u use the bulbs...
i hope to get a 860w vert in the new room at some point soonish.

 

[flat9]

I've run the 860 on a shitchable magnetic ballast, remember 860w CMH MUST be hung vertically, they perform well, seaf0ur also has been using one with good results on a switchable ballast...
good lite, but not alot of power savings... .just a better spectrum and different output for basically the same draw, still imo worth a try.



once again, imo worth a try

I was under the impression that 2 x 315w would be better than the 860 (newer, more efficient bulb, or something?). Is this correct?

 

[flat9]

Speaking of which, does anyone grow vert with 2 x 315w? I'm very curious about this....

 

[Jhhnn]

hi

there seems to be many interesting hps retrofit cdms (philips cdm-tt, osram powerball etc.)in the smaller end. but they all seem to be closed rated.

Philips PGZ CMH lamps are available in both open & closed fixture rated models-

http://www.lighting.philips.com/pwc...literature/downloads/elite_design_guidev7.pdf

O rated Philips CDM lamps are easy to identify because of the inner quartz sleeve(s). The lamp pictured at the top of the above link is *not* O rated.

This lamp is O rated-

http://www.bulbamerica.com/products...6&cadevice=c&gclid=CLL1lYS2nsICFc1_MgodIzQA0A

Properly designed open luminaires will have the PGZX18 lamp holder. Enclosed rated lamps will not fit that holder. Open rated lamps fit both the PGZ18 & PGZX18 holders. pages 15-16.

In the first link, the fact that the rotational orientation of a 315 used horizontally actually matters somewhat was a surprise to me. The wire frame goes to the top. Pages 15, 19 & 20.

would aircooled closed reflector with glass be enough to hold the possible blast of failing lamp?

In all likelihood, yes. It's dependent on the particular reflector in question.

 

[a senile fungus]

That's a very unusual looking lamp - is that the same mogul base version that Advanced is selling?

Yes it is. I got two of them from Advanced.

I bought the socket and base from a local shop and cut off the male adapter they had on it and wired it directly to the ballast.

Is this an appropriate wavelength for flowering?

I sure hope so...

I looked at the spectrum differences between the two bulbs and I like the 4200k better. I'm vegging with them right now. They sure do look pretty underneath this light

I think they are superior to HPS for a few reasons. First is the spectrum. It is more full and therefore your plant maintains vigor indoors longer. It is no secret that a mother plant should be brought outdoors into natural sunshine for a few months every few years to maintain full vigor. This is because HPS lacks much in terms of spectrum.
Second is rate of degradation. These CMH bulbs stay at a higher output longer whereas HPS bulb light intensity seems to fade much faster from what I noticed.
Lastly, color. It is just more comfortable to work under lights that aren't orange.

Yes. I love working around these lights and I feel comfortable enough around them to wear short sleeves to feel the light on my skin. It feels nice during the wintertime, maybe I'm producing Vitamin D?... The bulbs don't get too hot at all. I can bump them with my arm and I don't even think it burns any hair off...

Speaking of which, does anyone grow vert with 2 x 315w? I'm very curious about this....

I just posted a couple of pictures above, maybe one or two pages back.

Transformers efficiency loss is usually in the neighborhood of 1.5 - 3% when fully loaded. I've never seen one that you couldn't touch, and the heat generated is where the loss goes. The amount of heat is dependent on the air flow across it, with no fan and simply radiating the heat, they get pretty damn toasty. With a small fan on them, I doubt that you would see any significant rise.

They are more efficient when loaded than not, so you are better off switching the primary side of the transformer with your lighting control rather than interrupting the output and leaving the transformer energized.

Amazon has a 500w voltage converter that is ready to go for under $30 which should easily handle the inrush current during startup and the ballast overhead losses. I don't think that you are going to size one much closer than that. Considering the price, I doubt that the efficiency is as good as industrial quality gear, but it's probably not too bad. - http://www.amazon.com/Goldsource®-V...keywords=voltage+converter&pebp=1416884243819

I've seen the Mogul>PGZ18 adapters from several sources, you should be able to just Google it. I know that Mitronix makes them, but they have minimum orders. If you want to go the other way, PGZ18>Mogul, I've never seen one. http://lighting.mitronix.com/item/a...13b?&plpver=10&origin=keyword&filter=&by=prod

I decided to go big on the wattage of the transformers and get 750w for each bulb/ballast. I figured I wanted about 50% load on the transformers. You said that they're more efficient with more load, does that mean that I am putting more strain on my transformers by only running them at 50%? They don't get hot, just slightly warm; the ballasts get warm definitely, and they were kinda hot until I put spacers beneath them, but now just warm.




Overall I'm very impressed with these light over what I've seen HPS of similar wattage put out.

 

[rives]

You said that they're more efficient with more load, does that mean that I am putting more strain on my transformers by only running them at 50%?

No, not at all. Transformers are typically just a little more efficient if they are running at a higher load percentage. I doubt that the difference would be more than a couple percent, worst case.

 

[Jhhnn]

Rives is right as usual. A 750w transformer is loafing at 350w output. Like people, it's less efficient when it's loafing. Won't hurt it a bit.

 

[beta]

Is anyone here successfully using a 500W transformer to power a single 315W'r? Just want to make sure they can handle the startup spike and all that.

 

[Mate Dave]

I'm sure there used to be 1000w CMH.

 

[fungzyme]

Is anyone here successfully using a 500W transformer to power a single 315W'r? Just want to make sure they can handle the startup spike and all that.

I also got a 750w to use with my 315w ballast/lamp, because it wasn't really that much more expensive than the 500w and I wanted to make damn sure that it could handle startup. I read somewhere that you wanted a transformer capable of 50% more wattage than the device you are powering and that put the transformer required at just below 500w.
I figured a little excess capability couldn't hurt...

That said, if Rives says a 500w transformer is sufficient than I would feel okay going with that. He knows his shit.

 

[CMH]

Good points all around, rives.

That's how we first tested Greenbeams with the Philips ballast, using a step-up transformer for 120v wall outlet.

The nice parts about that route are the grower gets to use the Greenbeams luminaire and Philips ballast for 120v outlet with out much effort - and if in the future higher voltage outlet is available the grower doesn't need to buy a new ballast (not sure if the Welthink does 240v and 120v).

Welthink 315W CMH ballast works on both 120V and 240V.

 

[CMH]

I was under the impression that 2 x 315w would be better than the 860 (newer, more efficient bulb, or something?). Is this correct?

Philips 315W CMH has two color temperature bulbs: 3000K and 4000K, 860W has only one color temperature bulb: 4000K.

Bulb luminous efficacy:
315W CMH 3000K: 115Lm/W
315W CMH 4000K: 109Lm/W
860W CMH 4000K: 95Lm/W

 

[CMH]

whats up with the 315w bulb with mogul style base? is it that different from the pgz socketed 315w?

PGZ18 or PGZX18 socketed 315W has 3000K bulb, but mogul base 315W doesn't.

 

[CMH]

Can u use cmh in a vertical set up? Is anyone doing it that can point me to a thread to look at?

thanks.

If working with Welthink 315W CMH digital ballast, you can install Philips 315W CMH bulbs vertically and horizontally.

 

[CMH]

I'm sure that's true of their model for the 315. It has to be. Not likely for the rest of their lineup.

Everywhere I look, it says "call for pricing" & the combo deals are actually more expensive than the advanced lighting deal and a voltage converter. That's easily the best deal for tinkerers. Plug & play at 120v? $450-550.

Unless you get lucky on something used, 315w systems are pricey. I know a lot of people would like to find a less expensive way, but there's no getting around the fact that a special ballast is required from philips, welthink or maybe some others.

You can find some 315W CMH digital ballasts (brand new or used) on eBay. Here is one: http://www.ebay.com/itm/UL-CUL-list...c-metal-halide-digital-ballast-/281514923544?

 

[CMH]

so does no one know for sure if Welthink ballast are low freq, or not?

I know that Welthink 315W CMH ballast is low frequency.

 

[CMH]

Note the Welthink ballast will produce about 4% less umol/s than a Philips ballast for a 315W lamp (like the Philips CMH lamps under discussion here).

That is true with their 1st gen, their 2nd gen is as good as Philips. Now their 315W CMH is 3rd gen.