Growers Choice 315W Ceramic Metal Halide CMH Lamp 4200k

Growers Choice 4K 315W single ended CMH lamp for veg and full-cycle rooms Clone and veg rooms are where this lamp earns its keep. It is the 4200K lamp in the Grower's Choice single-ended range, part CMH-315W/942/PGZX18, SKU GC315W4K01. It puts out 540 µmol/s and 33,000 lumens after 100 hours, or 110 lm/W. Colour rendering is rated at 97, which is about as close to daylight as a discharge lamp gets. Rated life is 15,000 hours on ten-hour starts. Electrically it runs at 100V and 3.15A on a C182/O-rated or electronic ballast. The base is PGZX18, and the lamp is rated for open or enclosed fixtures in any burning position. Base temperature tops out at 250°C and bulb temperature at 350°C. Those are ordinary numbers for a 315W ceramic lamp. The warm 3100K lamp in the same line shares every electrical figure, so both run on the same ballast. Where a cool single ended CMH bulb fits in the room At this colour temperature the lamp sits on the edge between transitional and vegetative light. Growers run it over mother plants, fresh clones and young veg, and in single-lamp tents that go start to finish. The blue-rich output tends to keep internodes short and branching tight before flip. That high colour rendering also makes scouting easier, because leaf colour under it looks close to natural. Hang it higher over fresh cuttings and lower it as the canopy thickens and roots fill the pots. Next to other 315W ceramic lamps it sits at the low end on PAR and UV. 315W ceramic lamps sit within a narrow band on PAR, so the gap is small in practice. It is not the pick for maximum photons in flower, where the warm lamp in the range does better. Plenty of growers run one of each in a two-light room, which blends the two spectra without swapping bulbs at flip. Drive it with a low-frequency CMH ballast, since HPS and MH ballasts will not run it. It ships as a bare lamp, with the reflector and ballast sold separately. Key Features 540 µmol/s Photon Flux: A known PPF figure makes veg-room planning a matter of arithmetic. CRI 97 Colour Rendering: Near-daylight rendering shows deficiencies and pests clearly during scouting. 4200K Veg and Full-Cycle Spectrum: Blue-rich light keeps young plants compact before the switch to flower. 15,000-Hour Rated Life: Rated at ten-hour starts, it covers many veg cycles before replacement. PGZX18, Any Burn Position: Fits standard single-ended 315W reflectors, open or enclosed, in any orientation. Same Ballast as the 3100K Lamp: Swapping to the warm lamp at flip needs no change of ballast or socket. Technical Specifications Specification Value Part Number / SKU CMH-315W/942/PGZX18 / GC315W4K01 Lamp Type Ceramic metal halide (CMH/LEC), single-ended Wattage 315W Color Temperature 4200K Growth Phase Vegetative / full-cycle Lumens @ 100 hrs 33,000 Efficacy 110 lm/W CRI 97 PPF 540 µmol/s Rated Life 15,000 hours (10-hour starts) Base PGZX18 Lamp Voltage / Current 100V / 3.15A Min. Open Circuit Voltage 198V RMS Ballast C182/O or electronic CMH Burning Position Universal Luminaire Open or enclosed Max. Base / Bulb Temperature 250°C / 350°C