Overview -
I've been debating about making a thread for the Philips 315w CDM Elite lighting for some time - the main CMH thread has gotten so large that it is very difficult for people to access information on this particular variant of the CMH family. There is an immense amount of good data there, and I would encourage people to read it simply for the background, but I would like to keep this thread focused on the 315. There are enough variations of it to create plenty of confusion all by itself, so I'll leave the other members of the CMH family to those that have experience with them.
First, an overview and a bit of my personal history with lighting. I've used most of the available technologies over the years and had most recently dabbled pretty heavily with LED fixtures. I had built my Hybrid PL-L/LED fixture after using a Lumigrow ES330 for a while, and was getting ready to update it from PL-Ls to white LEDs. Spurr had made occasional mention of a revolutionary new CMH fixture that Cycloptics was developing, and it had caught my interest since I had used MH in the past and much preferred the natural spectrum over HPS. Although LEDs and the Hybrid had worked well, I disliked the "Martian Landscape" effect from the predominantly red/blue mix. The Hybrid worked well in that respect because I could simply turn off the red LEDs while working on the plants, but the cost and extensive labor involved in updating the fixture had me considering alternatives.
I'd been in contact with Cycloptics for quite some time while they were in development, and was ready to make a decision just as their product came to market. However, their fixture was (and still is) only available as an open fixture and I needed enclosed fixtures because I don't run A/C. I'd been monitoring eBay for quite a while, and some 315 ballasts and 930 T9 lamps started showing up from industrial auctions so I decided to build my own fixtures. The Bell 600w reflector wound up being the perfect size for my applications, and once I could find the damn sockets (see below), I was on my way.
As it turned out, the fixtures were easier to cool than my LED fixtures had been. This was because the LEDs just kicked the heat into the tents and depended on overall ventilation to cool things, whereas with the Bell hoods I re-directed that same airflow through the reflectors and moved the hot air out of the tents before it had a chance to heat anything up. The light is about as "natural" as indoor lighting can get, the plants are infinitely easier to troubleshoot and far more pleasant to spend time with. As a side benefit, yield went up by roughly 20% and there was no longer a need for the SCROG screen and intense canopy management because penetration is so much better. I seriously doubt that there are any commercial LED fixtures currently available that can touch the performance of the 315s, although the advent of white COBs has once again got me interested in DIY.
This technology, in my view, is best suited to small growers. By the time you get up to around 2000w of lighting, you are looking at a damn serious investment with these unless you luck out and find a bunch of parts from eBay or an industrial liquidator and are capable of building your own gear. I bought ballasts for $35-50 each, but it seems like sellers have caught on to the value of the parts now. The good thing is that with wider interest, the price of lamps has come down from absurd (@$500 each) to somewhat reasonable ($70-100)
I've been debating about making a thread for the Philips 315w CDM Elite lighting for some time - the main CMH thread has gotten so large that it is very difficult for people to access information on this particular variant of the CMH family. There is an immense amount of good data there, and I would encourage people to read it simply for the background, but I would like to keep this thread focused on the 315. There are enough variations of it to create plenty of confusion all by itself, so I'll leave the other members of the CMH family to those that have experience with them.
First, an overview and a bit of my personal history with lighting. I've used most of the available technologies over the years and had most recently dabbled pretty heavily with LED fixtures. I had built my Hybrid PL-L/LED fixture after using a Lumigrow ES330 for a while, and was getting ready to update it from PL-Ls to white LEDs. Spurr had made occasional mention of a revolutionary new CMH fixture that Cycloptics was developing, and it had caught my interest since I had used MH in the past and much preferred the natural spectrum over HPS. Although LEDs and the Hybrid had worked well, I disliked the "Martian Landscape" effect from the predominantly red/blue mix. The Hybrid worked well in that respect because I could simply turn off the red LEDs while working on the plants, but the cost and extensive labor involved in updating the fixture had me considering alternatives.
I'd been in contact with Cycloptics for quite some time while they were in development, and was ready to make a decision just as their product came to market. However, their fixture was (and still is) only available as an open fixture and I needed enclosed fixtures because I don't run A/C. I'd been monitoring eBay for quite a while, and some 315 ballasts and 930 T9 lamps started showing up from industrial auctions so I decided to build my own fixtures. The Bell 600w reflector wound up being the perfect size for my applications, and once I could find the damn sockets (see below), I was on my way.
As it turned out, the fixtures were easier to cool than my LED fixtures had been. This was because the LEDs just kicked the heat into the tents and depended on overall ventilation to cool things, whereas with the Bell hoods I re-directed that same airflow through the reflectors and moved the hot air out of the tents before it had a chance to heat anything up. The light is about as "natural" as indoor lighting can get, the plants are infinitely easier to troubleshoot and far more pleasant to spend time with. As a side benefit, yield went up by roughly 20% and there was no longer a need for the SCROG screen and intense canopy management because penetration is so much better. I seriously doubt that there are any commercial LED fixtures currently available that can touch the performance of the 315s, although the advent of white COBs has once again got me interested in DIY.
This technology, in my view, is best suited to small growers. By the time you get up to around 2000w of lighting, you are looking at a damn serious investment with these unless you luck out and find a bunch of parts from eBay or an industrial liquidator and are capable of building your own gear. I bought ballasts for $35-50 each, but it seems like sellers have caught on to the value of the parts now. The good thing is that with wider interest, the price of lamps has come down from absurd (@$500 each) to somewhat reasonable ($70-100)
