ViparSpectra - KS3000 320W LED Grow Light

A full-spectrum LED grow light of 320 watts built with Samsung LM301H diodes, for a growing area of roughly 90 × 90 cm. Dimmable, linkable and passively cooled, with a 3 metre power cable.

The diode is the component that counts

A grow light is a frame with a driver and a few hundred diodes on it. Of those three, the diode decides how much light comes out per watt, and it is the only part manufacturers name.

Here there is a name: Samsung LM301H. It is one of the better known white diodes in horticultural lighting, from a series whose successive generations each stepped up in efficiency. That a maker states the type rather than "high quality LEDs" is information in itself: it is checkable, and it makes comparison between brands possible.

Why that is worth having: between two lamps of the same wattage and shape, the difference in output lies almost entirely in which diodes are fitted and how hard they are driven. Diodes running well below their maximum are more efficient and last longer than the same diodes pushed to their limit, which is why a maker would rather fit more of them running gently.

What the efficiency figure here actually means

On light output there is one thing worth reading carefully. ViparSpectra states no PPF for the KS3000, so the number of photons per second appears nowhere. What the maker does publish, in the manual, is a usable PPE of 2.38 µmol/J, measured in a 3 × 3 foot tent.

That is a different kind of number from the efficiency on the XS1500 Pro and KS5000 pages, and the two cannot simply be set side by side. An ordinary efficiency figure counts every photon leaving the fixture. Usable PPE counts only what actually lands on the growing area: light falling on the tent wall or spilling past the edge does not count. Usable therefore comes out lower by definition than the number lamps are normally advertised on.

Two things follow. The 2.38 is a more honest number than most published figures, because it is about light arriving at your plants rather than light leaving the lamp. And you should not compare it with the KS5000's 2.459 or the XS1500 Pro's 2.199: measured the same way, the KS3000 would come out above that 2.38. If you want the three genuinely on one line, ask us and we will check it with the maker.

Technical Specifications:

• Power draw: 320 W
• LED type: Samsung LM301H
• Usable PPE: 2.38 µmol/J, measured in a 3 × 3 foot tent
• PPF: not stated by the manufacturer
• Coverage: roughly 90 × 90 cm, that is 3 × 3 feet
• Hanging height in flower: 30 cm, giving around 1000 µmol/m²/s under the lamp
• Hanging height for cuttings and veg: 60 cm
• Spectrum: full spectrum
• Control: built-in dimmer
• Linking: daisy chain
• Heat removal: passive, fanless aluminium heatsink
• Power cable: 3 metres

Frequently asked questions

How many µmol/s does this lamp give?
The manufacturer does not state that figure, and we do not substitute an estimate. There is a usable PPE of 2.38 µmol/J from the manual.

Why can I not set that 2.38 beside the other lamps?
Because usable PPE counts only the light landing on the growing area, while an ordinary efficiency figure counts everything leaving the lamp. Measured the same way, this lamp comes out higher.

What size space is this lamp for?
Roughly 90 × 90 cm, that is a 3 × 3 foot tent.

Can I dim it?
Yes, it has a dimmer, and several lamps can be linked.