Are this philips 360w CMH better than 315W ones?

Jhhnn said:

If you intend to use a mogul lamp reflector then this lamp requires no adapter-

MasterColor CDM Elite CDM 315/U/O/4K ED37

It's the 4200K version which I have not used but others report good results. It's open fixture rated.

Another member brought this ballast to my attention-

Amazon.com : C.M.H. 630 Remote Dual Lamps : Patio, Lawn & Garden

I haven't used it, either, but it seems like a reasonable possibility.

I suspect that T9 lamps are slightly cheaper in the commercial lighting market than T12's due to simpler construction. The vast majority of commercial lighting fixtures are enclosed. Performance is functionally identical at the same color temp across all Philips 315 lamp packages.

I've been using genuine Philips 3100K lamps for two years & likely won't change when I relamp after the current batch. I might go with their 4200K lamps if I can find a killer price but otherwise intend to stick with Philips lamps. I seriously doubt that others are any better & could be worse in terms of lumen maintenance so I stick with what I know.

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this looks like the answer Jhhnn. rated 'open fixture' is double glass bulb?

Thank you all for the information.. going to replace 600w LED (used for summer months) with 2x 315w for winter to add a few degrees of warmth..

Thanks Jhhnn, that confirmed what I suspected. Will buy kit locally, ask if they can substitute bulb and if not I'll get it anyway. By the time I need a replacement they should be a lot more available and and a better price

Cheers

Snook said:

this looks like the answer Jhhnn. rated 'open fixture' is double glass bulb?

Thank you all for the information.. going to replace 600w LED (used for summer months) with 2x 315w for winter to add a few degrees of warmth..

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Correct. This 315 lamp is intended only for enclosed fixtures-

https://www.amazon.com/Philips-2206...5&sr=8-2-fkmr1&keywords=philips+315w+cmh+bulb

This 315w lamp can be used in open or enclosed fixtures-

https://www.amazon.com/Philips-2380...5&sr=8-4-fkmr1&keywords=philips+315w+cmh+bulb

It's the same lamp with an extra glass envelope wrapped around it & secured with the metal band at the base.

I think it's very important to observe the open/ enclosed fixture ratings. The reason Philips went to ceramic emitters rather than the quartz used in conventional MH is that it's stronger so they'll operate at higher pressure. The chances of explosive failure with a single jacketed lamp are apparently quite small but not small enough.

High velocity flying white hot shit can be a serious problem that we all want to avoid.

Jhhnn said:

Correct. This 315 lamp is intended only for enclosed fixtures-

https://www.amazon.com/Philips-2206...5&sr=8-2-fkmr1&keywords=philips+315w+cmh+bulb

This 315w lamp can be used in open or enclosed fixtures-

https://www.amazon.com/Philips-2380...5&sr=8-4-fkmr1&keywords=philips+315w+cmh+bulb

It's the same lamp with an extra glass envelope wrapped around it & secured with the metal band at the base.

I think it's very important to observe the open/ enclosed fixture ratings. The reason Philips went to ceramic emitters rather than the quartz used in conventional MH is that it's stronger so they'll operate at higher pressure. The chances of explosive failure with a single jacketed lamp are apparently quite small but not small enough.

High velocity flying white hot shit can be a serious problem that we all want to avoid.

Click to expand...

So an 'enclosed' vs 'open' hood in CMH world has nothing to do with glass enclosure as in HID world? 'Enclosed only refers to the bulb not being exposed to breakage, while the open hoods' bulb is less protected from accidental breakage.. A whole new world to me. Thanks.

Snook said:

So an 'enclosed' vs 'open' hood in CMH world has nothing to do with glass enclosure as in HID world? 'Enclosed only refers to the bulb not being exposed to breakage, while the open hoods' bulb is less protected from accidental breakage.. A whole new world to me. Thanks.

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Not quite. Enclosed vs open fixture rating also has to do with spontaneous explosive emitter failure. The emitter is the small enclosure within the lamp that contains the excited gasses. MH emitters operate at higher pressures than HPS emitters & CMH emitters at even higher pressures.

Explosive failure of the emitter in HPS lamps generally won't rupture the outer glass envelope because the pressure isn't high enough. MH lamps do have enough pressure to do that w/o additional layers of glass & CMH even more so.

In the commercial lighting realm open MH fixtures use the EX39 socket. Lamps must have an extended center contact to fire in such a fixture & open rated lamps are made that way. Enclosed fixtures use the older E39 socket so both O & E rated lamps will fire in them.

That all goes to Hell in a handbasket wrt conventional grow fixtures, unfortunately, because they all use E39 sockets to accommodate HPS lamps that don't have the extended center contact. It's particularly problematical at 1000w where growers can just flip the ballast switch to MH & blithely run E rated lamps in an open fixture.

The difference between O & E rated mogul base lamps is readily apparent-

https://blog.1000bulbs.com/home/buying-a-metal-halide-bulb-4-factors

It's a very good thing that explosive failure of E rated MH lamps is quite rare. OTOH, none of us want to be the guy to experience it in an open fixture.