Uk people using 315 cmh?.

Flowki

Well-Known Member
As learned, the Phillips bulb works best on low frequency square wave. Running it on anything else creates ''light blink'' and reduces total light out put (as much as I could gather). In the UK, good luck getting a lowF sqr wave ballast for a reasonable £150 or lower price. Links if you can ;/. Prices seen + shipping in most cases range from £250-400 for ballast alone.

The cheaper uk ballasts/kits seen so far are maxi bright high freq, none square wave and Omega that I only assume is of similar or worse specs/output. Then theirs this ridiculously priced thing that seems to care more about looking sexy than specifying what specs the ballast runs on. No offense to anybody who bought one of those.. but fkin hell, extortion.
Anyway, a lot of uk grow shops are stocking the more modestly priced maxi bright or similar so it's the only plausible option.

My question is, does such a ballast run the bulb well enough to still make it a better veg light than a traditional 400W mh on a mag ballast.

If you've used both products your insight is very welcome. Or ofc, if you have a good understanding of why the bulb is most optimal on square wave perhaps you can chime in with how you think the bulb would compare with the question above.
 

Fevs

Well-Known Member
Yes a 315w cmh is better than a 400w mh. Plus it's much cooler, like almost the same as a 250w mh. I have two dr120's with two 315w cmh in each, 1 agro and 1 daylight in each, separate reflectors. I use maxibright ballasts and the philips lamps. What flicker? :D

I love using cmh lights for my growing bongsmilie
 

Flowki

Well-Known Member
Yes a 315w cmh is better than a 400w mh. Plus it's much cooler, like almost the same as a 250w mh. I have two dr120's with two 315w cmh in each, 1 agro and 1 daylight in each, separate reflectors. I use maxibright ballasts and the philips lamps. What flicker? :D

I love using cmh lights for my growing bongsmilie
A knowledgeable poster on rui states that square wave low freq is what runs the bulb to optimal out put. From what I gather he said the high frq none square wave means the bulb is not at a constant stream but blinks (very fast). The gaps between the blink mean it is 30% less efficient. Maybe I got this wrong but I drew the conclusion that he means the maxi ballast only puts out 70% of the total light it can with a square wave ballast. So that was my question, is 70% worth of maxi cmh better than a normal 400W mh mag light.
 

Fevs

Well-Known Member
I didn't know about the frequency thing. Are there any lamps that work better with the high frequency ballasts?
 

Flowki

Well-Known Member
I didn't know about the frequency thing. Are there any lamps that work better with the high frequency ballasts?
I don't know, sounds safe to assume not since they are all the same type of bulb.

The people at the local stores also didn't know anything about square and low ballasts. It's not encouraging ;/.. they should probably know this stuff.

Have you used a 400mh before?. If so, have you found the maxi cmh to have noticeably better veg growth?. It's really the comparisons I'm hoping somebody can make.
 
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Fevs

Well-Known Member
I have used 4500k philips master metal halide before, the cmh is better than that. I also flowered under the daylight too and vs the mh i got over 1 gram per watt with the daylight lamp, and 60% of that with the mh. It's worth doing imo. Up to you though, it won't make that much difference. Expect similar growth, maybe 10-20% better, with less heat and lower ambient temps in the grow room. I made the plunge. I use it for the whole cycle though. 1 daylight and 1 agro lamp in each set up. I'm a bit pissed with maxibright as they mention in their sales pitch that the omega ballast is the lower frequency and cannot power these lamps correctly.
 

Flowki

Well-Known Member
I have used 4500k philips master metal halide before, the cmh is better than that. I also flowered under the daylight too and vs the mh i got over 1 gram per watt with the daylight lamp, and 60% of that with the mh. It's worth doing imo. Up to you though, it won't make that much difference. Expect similar growth, maybe 10-20% better, with less heat and lower ambient temps in the grow room. I made the plunge. I use it for the whole cycle though. 1 daylight and 1 agro lamp in each set up. I'm a bit pissed with maxibright as they mention in their sales pitch that the omega ballast is the lower frequency and cannot power these lamps correctly.
The emphasis seemed to be more on the square wave part so perhaps freq is off less importance, assuming the omega is not square wave. I did however recall reading something about omega ballast only being able to run the bulb on a lower W setting.. obviously no good at all if true, but that may have been an older model omega. Maxi did seem like the only real option, but, still trying to convince myself to buy it ;/. Cooler running 10-20% better growth with summer temps sounds good. How would you rate the cmh against a 600W dual spec hps in cooler winter months?.
 

Fevs

Well-Known Member
I'm getting 27oc now with extraction running so slow that I have to turn off the intake fan. I estimate that to keep them warm on 24-0 in the winter I'll be adding 1 250w sunmaster mh to each set up. It so much cooler.

2 tents dr120 with daylight and agro, sweet seeds afghan del + fb#2

Do it man! These lights are effing brilliant. I invested in 3, I already had the D papillon and was already sold on cmh from that lamp. I took the plunge, which seems a lot, I bought 2 agro and 1 daylight single kits from maxibright. These only regret I have is not doing it sooner :weed:

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Fevs

Well-Known Member
Those last plants are day 26 from seed.

These next are day 19 from seed. Sweet Seeds Sweet Cheese auto. Ds120 - 1 agro, 1 daylight.

At the end of the day there are no led's as good as cmh. Yet it would costs way more to get this amount of usable light. These are like 450w-500w of hps, so 2 of these in theory would piss all over a hps. I'm trying 3ft away from the lamps currently, leaves are cool, plants are happy as a pig laying in it's own shit! :leaf:(:

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Fevs

Well-Known Member
Any updates on this? What's the best option for UK people?
What is you set up and how much weed do you want to grow? If you have a 1.5m tent, i'd say go with 1000w duel spec hps, unless you have money to piss and can kit it out with four x 315w cmh units. If you have a 3ft tent go with 1 x 315w cmh or 4ft tent - 630w cmh.

MAinly, ask yourself how much weed you want to grow. That helps a lot. If it's 30 ounces 1000w hps. if it's an ounce or 2 a small led would do nicely.
 

JDMase

Well-Known Member
What is you set up and how much weed do you want to grow? If you have a 1.5m tent, i'd say go with 1000w duel spec hps, unless you have money to piss and can kit it out with four x 315w cmh units. If you have a 3ft tent go with 1 x 315w cmh or 4ft tent - 630w cmh.

MAinly, ask yourself how much weed you want to grow. That helps a lot. If it's 30 ounces 1000w hps. if it's an ounce or 2 a small led would do nicely.
Just want to know what 315w CMH is best value for money in the UK, the sun systems or the cheaper ones like maxibright or something.. Personally in a 1mx1m looking for something for a veg tent
 

Fevs

Well-Known Member
Just want to know what 315w CMH is best value for money in the UK, the sun systems or the cheaper ones like maxibright or something.. Personally in a 1mx1m looking for something for a veg tent

Then yes... its far better than the alternatives! The 4200k lamp is a delight to grow under!
 

Fevs

Well-Known Member
Which brand of light do you suggest? Ive seen a few and can't really decide!
I like the maxibright one's. They do a kit with the mini supernova, lamp and ballast. Good value for cmh!

Also got the D Papillon which is well heavy, with built in ballast.

The maxibright ballast gets fucking hot, so I use a clip on fan to aim just at the ballast too. They get hotter than a 600w lumatek ballast, yet feels like no heat whatsoever with the clip on fan there!

The D Pap runs hot too. Maybe it's a cmh thing.

You can't go wrong with daylight lamp (4200k), maxibright ballast and the mini supernova! That's one supreme bit of kit! The spectrum of the daylight lamp is so good! I flowered with the daylight lamp and got over 1 gram per watt too!

This plant is right next to the daylight cmh. Look at her leaf pray! lol

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JDMase

Well-Known Member
I emailed the eBay shop regarding their CMH and I got this response, I thought I'd post it incase anyone stumbles across the thread and it answers any questions.

"These lights are like mini gravitas, I've not seen the Sunsystems light so can't comment on similarities. I can tell you the 315w digital ballast uses a low frequency square wave electrical current which is apparently better for CDM bulbs.

The 315w CDM Agro bulb has a colour temp of 3100k and is ideal for veg & flower. The bulb is not branded Philips but it is identical in every way. The light they give off is just like bright sunlight."

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Fevs

Well-Known Member
I emailed the eBay shop regarding their CMH and I got this response, I thought I'd post it incase anyone stumbles across the thread and it answers any questions.

"These lights are like mini gravitas, I've not seen the Sunsystems light so can't comment on similarities. I can tell you the 315w digital ballast uses a low frequency square wave electrical current which is apparently better for CDM bulbs.

The 315w CDM Agro bulb has a colour temp of 3100k and is ideal for veg & flower. The bulb is not branded Philips but it is identical in every way. The light they give off is just like bright sunlight."

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Nah mate, there are 2 lamps. The 3100k is good, but imo the daylight lamp is far better. I bought mine off ebay. I have 4 cmh kits. 2 3100k and 2 4200k.

If I did it all again I'd get just daylight lamps
 

Fevs

Well-Known Member
Now rolling with 315w cmh 4200k, alongside 315w cmh 3100k, one 2ft tube T5 (6500k) and 4 leds. This mixed spectrum of blurple leds alongside mixed spectrum cmh is a true pleasure to grow under! 4ft x 4ft tent

1 month left for these 5 auto's. Love growing under cmh! The further the grow goes, the more it amazes me!

I've backed the lights off since adding more light. Reduces the heat stress, but wanted to find the perfect distance. Not like I've got to worry about light coverage lol

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