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CMH Lights?

J

Jason

New member
Looking at adding to and upgrading my lights. A friend suggests a 300W CMH. I'm wondering about heat and power consumption.
I'm using (2) 300 W LED's now and heat is non existent in my environment. Sounds like the CMH would need some ventilation.
The projected yields look good.
What should I know?
 
Power consumption would be less for sure than 2 300 watt leds... Heat is super minimal..what's your grow space size...
 
Thanks for posting, gents.
I'm using a shower/tub for a grow space. Couldn't be more convenient for dealing with hydro.
It will have the two 300W LEDs and the new 300W CMH for two Water Farms.
I was doing the math for 24 hours on, not 18 and then 12. Once I corrected for that, things looked better.
Heat is my main concern. I'm dealing with almost none now, so I know that will change. But if CMH is cooler than LED, that should be no problem.
Thanks in advance for any insights.
 
Yea my ballast probably puts out more heat than the light does. I opted for the cooling kits. I run 2 phantom 315 LECs in a pretty large flower room absolutely minimal heat compared to my old HPS system. Oh yeah the cooling kits for a waste of money don't buy them.
 
I'm useing a 1000w Double ended Hps
and 1, 1200w LED AT 12 hrs a day.
plus 1 1200 LED in my Veg room at 18 hrs a day.
All the fans running, charcoal scrubber running.
and my hydro bill has gone up 95 bucks a month from this.

I ran the Metel Halide bulb in it for one month and it was the same.

if you can I would go with the Double ended lights with digital ballist and a vented hood. stick a duct fan in it blow the heat out the room with dryer hose.
they come with 15 feet of cable so you can have the ballist out side the room.
They are 30% more efficient then the ceramic lights.
this is how I'm set up and I love it
research it....


​​​
 
Last edited:
4barrel said:
I'm useing a 1000w Double ended Hps
and 1, 1200w LED AT 12 hrs a day.
plus 1 1200 LED in my Veg room at 18 hrs a day.
All the fans running, charcoal scrubber running.
and my hydro bill has gone up 95 bucks a month from this.

I ran the Metel Halide bulb in it for one month and it was the same.

if you can I would go with the Double ended lights with digital ballist and a vented hood. stick a duct fan in it blow the heat out the room with dryer hose.
they come with 15 feet of cable so you can have the ballist out side the room.
They are 30% more efficient then the ceramic lights.
this is how I'm set up and I love it
research it....


​​​
Click to expand...

Thanks for posting! I like the 30% more efficient, but I wonder about wavelengths that plants like/need. LED's seem to still be developing. I do like the two I have.
The CMH is getting good reviews in that regard and grams per watt.
I'll go look at the unit and decide. Its on sale and I do need to upgrade my light situation.
 
Jason said:
Thanks for posting! I like the 30% more efficient, but I wonder about wavelengths that plants like/need. LED's seem to still be developing. I do like the two I have.
The CMH is getting good reviews in that regard and grams per watt.
I'll go look at the unit and decide. Its on sale and I do need to upgrade my light situation.
Click to expand...

I think The 1000w D.E. HPS is getting 1gm per watt. cant quite remember
but I think that's what it is
I know there's a review on them on you tube or Google.

also with a dimable digital ballist.
it has 4 settings
-500w
-750w
-1000w
-1150w (Super Lumins)

so as your plants get older ya turn it up gradualy as ya raise your light.
But the super Lumins is a bit much.
I guess you can use it if your growing full size tall plants. but In my scrog I just about cooked my plants.
so dialed it back down to 1000 and found the right distence

I'm deffinite getting a second one.
then set them on a 750w. disperse the light bit better and bring then down closer.

Also with a vented hood, I draw cool air in blowing through the hood and out the room. This way i seel my room and inject Co2 with out losing all my gas out through ventalation.
set a small fan on the floor pointing straight up ta keep pushing the gas up and off the floor.
 
Last edited:
Just got it. Looks like plug-n-play once you hang it. Which will be mon yanna.
Here are the details about the bulb. A friend uses two of these for a 4 x 8 ft grow space and is very happy. My space is pretty much 2 x 2, and I have (2) 300W LED's already installed.
So that should be plenty of light for my two Water Farms.

Just read that Philips developed the CMH and supposedly makes some of the best for flowering needs.

Details
Philips Elite Agro 315W T12 Lamp provides a compact and efficient metal halide solution for the horticulture market. This lamp, combined with the efficient ballast, provides outstanding growth light performance over the life of the product.

Superior color quality. Crisp white light. Incredibly high 1.95 PPF (photosynthetic photon flux) per watt per second light source. 3100k color temperature, High 92cri, 33,000 initial lumens (105Lm/W). High 90% lumen maintenance at 8,000 hr / High 85% PPF maintenance at 20,000 hr. Unique Open Rated Lamp construction reduces radiant heat from the arc tube and is suitable for open fixture use.

General Characteristics
Full product name: Mastercolor CDM-T Elite 315W T12 CL Agro P Short product name: CDM ELITE 315W/T12/AGRO
  • Watts: 315W
  • Lamp Voltage: 98 V
  • Lamp Current EL: 3.15 A
  • Avg. Hrs. Life: 20000 hr
  • Color Temperature: 3200K
  • Initial Lumens: 33000 Lm
  • Energy Efficiency Label (EEL) A+
  • Energy consumption kWh/1000h: 315 kWh
Edit- Just plugged it in for a heat check. This 300W CMH light is BRIGHT! compared to my 300W LED's. Hopefully, they will play well together.
Half an hour into the test and I'm impressed by how little heat is generated. It is one hot quartz bulb, but heat out put seems low.
 
Last edited:
Jason said:
Just got it. Looks like plug-n-play once you hang it. Which will be mon yanna.
Here are the details about the bulb. A friend uses two of these for a 4 x 8 ft grow space and is very happy. My space is pretty much 2 x 2, and I have (2) 300W LED's already installed.
So that should be plenty of light for my two Water Farms.

Just read that Philips developed the CMH and supposedly makes some of the best for flowering needs.

Details
Philips Elite Agro 315W T12 Lamp provides a compact and efficient metal halide solution for the horticulture market. This lamp, combined with the efficient ballast, provides outstanding growth light performance over the life of the product.

Superior color quality. Crisp white light. Incredibly high 1.95 PPF (photosynthetic photon flux) per watt per second light source. 3100k color temperature, High 92cri, 33,000 initial lumens (105Lm/W). High 90% lumen maintenance at 8,000 hr / High 85% PPF maintenance at 20,000 hr. Unique Open Rated Lamp construction reduces radiant heat from the arc tube and is suitable for open fixture use.

General Characteristics
Full product name: Mastercolor CDM-T Elite 315W T12 CL Agro P Short product name: CDM ELITE 315W/T12/AGRO
  • Watts: 315W
  • Lamp Voltage: 98 V
  • Lamp Current EL: 3.15 A
  • Avg. Hrs. Life: 20000 hr
  • Color Temperature: 3200K
  • Initial Lumens: 33000 Lm
  • Energy Efficiency Label (EEL) A+
  • Energy consumption kWh/1000h: 315 kWh
Edit- Just plugged it in for a heat check. This 300W CMH light is BRIGHT! compared to my 300W LED's. Hopefully, they will play well together.
Half an hour into the test and I'm impressed by how little heat is generated. It is one hot quartz bulb, but heat out put seems low.
Click to expand...

Ok well,
doing lots of research, research,research on diffrent options before purchase is all ways in your best intrest.
and it sounds like ya got this.
Hope it works for ya, Happy growing
 
Thank you.
I started with (2) $70 Full Spectrum (?) LED's from Amazon for the first grow, harvested early April.. Very happy with the results. Now trying to fine tune and up out put.
My friend that has been growing indoors since the '80's (Holland and US) uses these and likes them.
 
So I almost ruined the new light. Unplugged it after running most of the day, to plug into a timer. I DID NOT let it cool. It didn't start properly, so I immediately unplugged it. Now I'm told not to plug it in
while the ballast is hot. So I let it cool, plugged into the timer and all is well.
 
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