I've noticed a ton of love being shown to these 315w lights but not much is said on their dimming capabilities. Do they lose a lot of spectrum and output when dimmed like other HIDs? I've been debating getting a 630w (2 single 315s) fixture but it will be too hot for my small 3x3 tent. As such I was considering dimming it but can't find a lot of info on how they do when dimmed.
Dimmable cmh/lec...?
- Thread starter MedN00b
- Start date
hotrodharley
Well-Known Member
Farmer.J
Well-Known Member
You should get a vertical 315 cmh for that tent. Vertical has the most even lighting. Make sure the ballast is square wave w/4100k bulb. Heat would be nil and probably yield somewhere between what you would expect a 400w-600w Hps to do.
https://www.growlights.ca/growlights/grow-light-kits/ceramic-metal-halide-lights-cmh/silverstar-cmh-reflector-315w-ballast-system-w-philips-bulb.html
Farmer.J
Well-Known Member
That's a de HPS, way too big for a 3x3
hotrodharley
Well-Known Member
And your talking a 630CMH in the same tent? Interesting .
Farmer.J
Well-Known Member
No I said a vertical 315cmh
Big difference between that and a 1000w de hps
Gbuddy
Well-Known Member
Forgot where I ve read it but....
The Info I got years ago is that its not good to dim ANY MH.
If I remember right its fucking up frequency something. They said plants dont like it. And I hate that!
But maybe that cmh is different.
What ballast are you planning to use?
Peace
The Info I got years ago is that its not good to dim ANY MH.
If I remember right its fucking up frequency something. They said plants dont like it. And I hate that!
But maybe that cmh is different.
What ballast are you planning to use?
Peace
MichiganMedGrower
Well-Known Member
I wish I had saved all my links from my old phone but the Phillips 315 cmh bulb run on the galaxy dimmable ballast had charts posted at each wattage.
The spectrum looses the red peak the quickest but mostly goes down much more evenly than mh or hps. Which is degraded the worst because it is mostly red which degrades fastest without max wattage apparently.
In my 3x3 tent I often turn down to 80% to take some pressure off young plants. No problems seem to result.
If anything at 100% the plants stay too compact. And this is the 3100k bulb. Backing off the wattage helps with some stretch. The lamp is already hanging from the roof. And the plants are pretty much on the floor.
Pics from when I was dialing in for my perpetual garden. I grow the veg to get ready for the flower room from this tent.
The spectrum looses the red peak the quickest but mostly goes down much more evenly than mh or hps. Which is degraded the worst because it is mostly red which degrades fastest without max wattage apparently.
In my 3x3 tent I often turn down to 80% to take some pressure off young plants. No problems seem to result.
If anything at 100% the plants stay too compact. And this is the 3100k bulb. Backing off the wattage helps with some stretch. The lamp is already hanging from the roof. And the plants are pretty much on the floor.
Pics from when I was dialing in for my perpetual garden. I grow the veg to get ready for the flower room from this tent.
NugHeuser
Well-Known Member
One 315 will do great in a 3x3. Like others have said make sure it's a model that has the bulb positioned vertically and that the ballast is a low frequency square wave ballast.
I'm running 2 315s dimmed to 70%(summertime heat) in combination with 3 separate 3 cob rails, each cob being run at 33 watts inside an 8x4 tent and my plants are booming. Pretty good bud growth for how far into flower they are, and especially considering that I'm only running 23.15 watts per sq. ft.
If I could have it my way though I'd rather not dim at all. I'm able to run full power during the winter.
It may effect bulb life too though as well as spectrum by dimming, at least I've read.
I'm running 2 315s dimmed to 70%(summertime heat) in combination with 3 separate 3 cob rails, each cob being run at 33 watts inside an 8x4 tent and my plants are booming. Pretty good bud growth for how far into flower they are, and especially considering that I'm only running 23.15 watts per sq. ft.
If I could have it my way though I'd rather not dim at all. I'm able to run full power during the winter.
It may effect bulb life too though as well as spectrum by dimming, at least I've read.
Farmer.J
Well-Known Member
I have dimmable ballasts for my de630's and I never even put batteries in the remote controls. I would never run a bulb at a lower wattage than it is made for. Why don't you run 100% and take a few cobs out of the equation?
NugHeuser
Well-Known Member
Don't want to try fixing something that isn't broken, the plants speak for themselves.
NugHeuser
Well-Known Member
I'm experimenting with different things to get my temps down but until then everything will stay dimmed down a bit, doesn't look to be a problem so far. 
The plant above is at day 30.
As soon as I'm able to run 100% I will. My point being to the OP, is it wont make or break your grow to dim them.
The plant above is at day 30.
As soon as I'm able to run 100% I will. My point being to the OP, is it wont make or break your grow to dim them.
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Gbuddy
Well-Known Member
Man that bud is looking nice for only 30 days!!!
Good job!
NugHeuser
Well-Known Member
Thank you!