ThingsYou Should Know about CMH Grow Lights

Why are so many people considering growing plants indoors? The global warming trend makes gardening more difficult for many. People living in urban areas might not have any garden space available to them. Some people live in areas where the soil is poor and/or there are problems with animals eating their produce before they can pick it. Once the decision is made to grow plants indoors, the set up must be planned and executed. The most important factor in indoor plant growing is the lighting. Plants need a certain kind of light to thrive.

If you’ve been wondering about Ceramic Metal Halide or Light Emitting Ceramic grow lights, you’re on the right track. CMH grow lights are hands down the best HID grow lamp technology available on the market right now. Also known as LEC grow lights, they have the best PAR spectrum of any HID lamp, the slowest degradation rate, and they’re also at least 10% more efficient than other HID lamps.

What Is A CMH Grow Light?

Ceramic Metal Halide (CMH), Light Emitting Ceramic (LEC) and Ceramic Discharge Metal Halide (CDM) all refer to the same thing. CMH is the most common term. CMH grow lights are a variation of MH, but they are quite different. Instead of using a quartz tube, they use a ceramic one (more here), similar to an HPS bulb.

This allows a higher arc tube temperature, which in turn allows a better mix of gases to produce a more optimal spectrum (more on this below in the sections comparing CMH to MH and HPS). The light produced by a CMH bulb is much closer to natural sunlight than either metal halide or high pressure sodium (with a CRI of 96). It is, for practical purposes, a perfect combination of MH and HPS in a single bulb.

The Advantages of CMH Grow Lights

There’s a reason people are looking into CMH grow lights, and it’s the huge list of advantages when compared to almost every other grow light option.

Balanced spectrum

Not only do you get a more balanced spectrum that hits almost every sweet spot for your plants but they’re also better at turning your electricity into usable light.

By comparison, HPS and MH lights waste a lot of energy producing light at ranges that are not efficiently used by plants. This means that CMH are more PAR efficient than either HPS or MH, making them a better single light solution.

Color Rendering Index

They also have a more natural CRI (Color Rendering Index). CRI describes how the color of a light source changes how an object appears to the human eyes and how well subtle variations in color shades are revealed. The higher the CRI, the more realistic things look. CMH grow lights are generally rated between 80 to 96 CRI, by comparison, the sun is rated at 100 CRI. This means that CMH grow lights will let you see the true color of your plants without making your grow room look yellow, blue or purple.

Ultraviolet Radiation

CMH grow lights provide UV (ultra violet) radiation, which although being outside of our range of vision is beneficial (at certain ranges and intensities) to plant growth and development. They produce UV-A, UV-B and UV-C Light, but UV-C is generally very harmful to human eyes. So most high quality manufacturers use a glass filter to block the UV-C output while leaving UV-A and UV-B output intact.

Note: All HID bulbs emit some amount of UV radiation. The amount may vary and they’re sometimes shielded. But remember not to look at or work around a bulb with a broken outer glass jacket because UV radiation burns, and this damage is cumulative.

Longer Lasting

Ceramic arc tubes are more resistant to breakdown, so they last a lot longer than MH and HPS bulbs. In fact, CMH grow lights tend to last over 24,000 hours while keeping at least 80% of their original intensity at the 20,000-hour mark. This overshadows the common 10,000-hour replacement rule for HPS & MH bulbs.

Here are 3 great CMH lights recommended for you, I hope to help you.

ECO Farm CMH 630W Double Ended Grow Light Fixture

Features:

The ECO Farm CMH grow light has a high 1.95 PPF light source per second and 3100K color temperature. High 90 CRI. Optimal for flowering while also can be used for Veg as well. 33,000 initial lumens (105Lm/W). Promotes higher rate of metabolic activity and resin production through the use of UV far-red spectra. High 90% lumen maintenance at 8,000 hr/ High 85%. Expected Life Span (hr): 20,000. The unique open rated lamp structure reduces the radiation from the arc tube heat. Low heat, close to sunlight, can replace the traditional 600W 1000W plant light kit and 300w 600w 1000w plant light kit, CMH lamps can be used as the main vegetable light; the main light for SOG applications; or for large-scale flowering operations Spectrum lights. 630W can almost replace the 1000W HPS, but save about half electricity. 630W has a better spectrum, which makes grow efficiently.A higher temperature creating light much closer to the suns. Being able to operate more efficiently at higher temperatures means a boost in performance.

Exact Watts:630 Watts
Color Temp: 3100k
Input Wattage: 690~680W
Rated Main Voltage 120V 240V
Input Current 5.75A~2.84A
Input Frequency 50/60 Hz
Min Power Factor: 0.98
THD: <10%
Wave Crest Coefficient: <1.7
Required Lamp Voltage: 220v +/- 20v

Grower’s Choice 630W Dual Bulb CMH Light

Features:

The grow light has a horizontal design, which gives out the grower’s choice spectrum, which replicates the sun’s properties to boost the overall plant growth. The industry-leading ballast comes with a highly efficient dimming feature. It has two horizontally placed lamps, which allow you to mix spectrums to deliver a full phase broad spectrum for achieving maximum yields. The system has sophisticated software that saves it from under-voltage, over-voltage, short circuit protection, open-circuit protection, and over temperature.With proper heat dissipation, the system functions efficiently. As there are no internal fans used; therefore, it does not disturb the surrounding environment. The GC series digital ballast is 30% highly efficient compared to the standard magnetic ballast, which helps produce more lumens light per watt of consumed energy.

Exact Watts:630 Watts
Rated Main Voltage 120V 240V
Input Current 5.6A 2.8A
Input Frequency 50/60 Hz
Power Factor 0.97
THD: <10%
Required Lamp Voltage: 220v +/- 20v
Ignition Voltage: 3KV-5KV
Dim Settings: 380W, 490W, 630W, 710W
Coverage Area:Veg: 5' x 5'; Flower: 4' x 4'

Nanolux CMH 630W Double Lamp Fixture

Features:

CMH lamps have a very broad light spectrum which is more similar to the sun itself than any other form of HID lamp. Nanolux has taken CMH technology and increased its operational efficiency, making the most comprehensive spectrum of light output for an HID fixture even better. The CMH fixture can be used as a primary veg light or a supplemental full spectrum light. Get the best spectrum available for maximum potency of your plants using Ceramic Metal Halide lamps with enhanced UV. The CMH 630W dual lamp fixtures allow for any combination of 315W CMH lamp K temperatures. Meets ETL Standards and uses 97% German reflective material. Both Nanolux CMH fixtures can be used with any 315W 3K or 4K horticultural lamp from all the leading quality brands. The Nanolux CMH 630W Double Lamp Fixture hood is optically designed to give a balanced footprint and is perfect in larger grow environments . Light weight and cool running Nanolux ballast the industry has come to trust.

CF: less than 1.7
Input Voltage: 120/240V
Input Frequency: 50–60Hz
Voltage: 240V
Lamp Base: PGZX18
Cord: 120 Cord, 15 ft cord
Amperage Draw: 5.2/2.6
PF: >0.99
THD: <1.7

The Disadvantages of CMH Grow Lights

Weaker in Flowering Than HPS

When it comes to flowering crops, HPS lights are still the “HID King.” This is because HPS grow lights output more light in the red spectrum than CMH lights. Even still, the debate rages on. If you compare CMH to HPS on a watt by watt basis, CMH lights do have a more balanced PAR spectrum than HPS lights. And research is still being done to figure out if the added benefit of a better spectrum improves the overall crop even with the diminished harvest.

Heat Output

CMH grow lights usually output a lot of light in the infrared part of the spectrum (over 700 nm) which makes them output quite a lot of heat. Although it still less heat than other 400w HID bulbs, it’s noticeable even if they’re consuming a lower wattage.

Upfront Cost

Another disadvantage is the initial cost. Usually a high quality 400w MH or HPS grow light kit (including ballast, bulb and reflector) costs around $200, by comparison, the initial investment for a complete 315w CMH kit hovers around $500, which is a pretty hefty initial investment. However, in the long run CMH will still save you more energy.

Conclusion

There is no better single HID grow light solution available in the market. Not only do they save you energy and produce less heat per watt used and provide very good light spread, but they’re also a complete-cycle growing solution suitable for most green and flowering crops with their balanced spectrum output, UV supplementation and the capability to be hanged in any position over the canopy.

The only downside right now is their high price, which hopefully will decrease as they flood the market and become a more accessible option for growers looking to step up their grow.