Growlite 315W Double Ended Full-Spectrum CMH Lamp | 4000K, 512 µmol/s

Growlite 315W double ended full-spectrum CMH lamp for DE fixtures

This is Growlite's double-ended ceramic metal halide lamp, part GLL-315-CSI-DE, built for fixtures with K12x30s sockets at each end. Growlite rates it at 512 µmol/s of PPF and 31,460 lumens after 100 hours. Colour temperature is 4000K and colour rendering is CRI 95. Rated life runs to 20,000 hours on Growlite's sheet. It runs at a nominal 100V and 3.15A on an ANSI C182/O-rated ballast. The lamp is 394 mm (15.5 in) end to end, with a light centre length of 195 mm and a 61 mm bulb diameter. Growlite rates it for open or enclosed fixtures and any burning position. That is a useful combination for a DE lamp. It means the lamp can run bare in an open double-ended reflector or behind glass in a sealed hood. Growlite's 315W CMH electronic ballast was developed alongside its lamps, although any C182/O-rated CMH ballast will drive it.

Where a full spectrum ceramic metal halide lamp like this fits

At this colour temperature the lamp sits in the transitional band, balanced enough to run one spectrum from veg to harvest. That suits a single-light room where swapping lamps at flip is more hassle than it is worth. Growers who want the most bloom intensity usually pick a warmer lamp near 3000K instead. Hang it higher over young plants and lower it in stages as the canopy fills in and the stretch ends. The double-ended format needs a matching DE fixture, so it will not thread into a mogul or PGZX18 socket. Check the socket spacing on your fixture before ordering replacements, because DE lamp lengths differ between wattages and brands. Like every ceramic metal halide lamp, it emits UV, so avoid looking at the arc and wear CMH-rated eyewear when working close. Handle the quartz with gloves or a clean cloth, since skin oil on the glass shortens lamp life. Growlite does not publish a UV figure for it, and the lamp was not part of our own ten-lamp CMH test. Its long rated life still makes it an easy lamp to leave in service for several years.

Key Features

• 512 µmol/s PPF: A published photon figure lets you plan canopy intensity instead of guessing from lumens.
• 4000K, CRI 95: A balanced spectrum carries a crop from veg into flower without a lamp swap.
• 31,460 Initial Lumens: Strong output for the wattage keeps heat and power draw modest.
• K12x30s Double-Ended Base: Fits DE CMH fixtures built around the standard double-ended socket.
• Open or Enclosed, Any Position: The lamp runs bare in open reflectors or in sealed hoods, at any angle.
• 20,000-Hour Rated Life: Long rated life stretches replacement intervals across many cycles.

Technical Specifications