HLG-240H-C1750 with 4 Cree CXB3590's?

Hi,
I was looking at the Mean Well HLG-240H-C1750 on RapidLED for driving 4 Cree 3590's at 1750ma.

The Rapid web site suggests using this driver with 2-3 36v COBs.

I used a Cree online tool, and determined that at 1750 ma, the COBS are likely to have a voltage drop for 35.5 Volts. So 4 of these would total 142 volts. The spec sheet for the driver indicates that the driver is constant current up to 143 volts.

To me, it looks like it will work. (142 < 143) Am I missing something, or is this some sort of error at Rapid? (If the COB had an _actual_ voltage drop for 36 volts, the total would be 144, which would be 1 volt too high.)

Thanks for any input!

Taos said:

Hi,
I was looking at the Mean Well HLG-240H-C1750 on RapidLED for driving 4 Cree 3590's at 1750ma.

The Rapid web site suggests using this driver with 2-3 36v COBs.

I used a Cree online tool, and determined that at 1750 ma, the COBS are likely to have a voltage drop for 35.5 Volts. So 4 of these would total 142 volts. The spec sheet for the driver indicates that the driver is constant current up to 143 volts.

To me, it looks like it will work. (142 < 143) Am I missing something, or is this some sort of error at Rapid? (If the COB had an _actual_ voltage drop for 36 volts, the total would be 144, which would be 1 volt too high.)

Thanks for any input!

Click to expand...

If I remember correctly Meanwell underspecs their datasheets so you should be okay. I would like to hear it from someone that has the setup though.

It's not 143v.

https://www.rollitup.org/t/any-problems-using-hlg-240h-c1750-to-run-4-cxb3590s-36v.888362/

I used 4-cxb3590 36v cobs with a C1400B driver for 200w and 50w per cob. Going with 75w per cobs and 225 watts max with three cobs will be inefficient and hotter. The idea is to generate light without generating unnecessary heat. The higher wattage you run cobs the more heat the generate and the less usable light they generate. You can make your cobs blinding bright, but that does not mean that is the best light. Half of ALL light is unseen to the naked human eye. Plants use that light we can not see more efficiently than the light we do see.

I retired cobs this year as newer technology has arrived that makes cobs less effective than the current mid-power diodes from Samsung. Cree and Osram have joined forces to compete with Samsung a Korean/Japanese JV in the mid power horticulture area.

I now use Samsung diodes mounted on my own boards similar to ChilLED grow lights commercial;y available and parts and ;lights available to the public as well. I paterned my light engine after Vitaly's of ChilLed Grow Lights because I have studying him for a few years and now he has stepped out from the pack and show his lights are top notch, and not cheap either, but his light engines are affordable for DIY.

Taos said:

Hi,
I was looking at the Mean Well HLG-240H-C1750 on RapidLED for driving 4 Cree 3590's at 1750ma.

The Rapid web site suggests using this driver with 2-3 36v COBs.

I used a Cree online tool, and determined that at 1750 ma, the COBS are likely to have a voltage drop for 35.5 Volts. So 4 of these would total 142 volts. The spec sheet for the driver indicates that the driver is constant current up to 143 volts.

To me, it looks like it will work. (142 < 143) Am I missing something, or is this some sort of error at Rapid? (If the COB had an _actual_ voltage drop for 36 volts, the total would be 144, which would be 1 volt too high.)

Thanks for any input!

Click to expand...

When cobs turn on their vf is higher because they are cold which would mean your total volts would likely be higher than 143. You could cap the dimming wires on a 'B' version of the driver and run them at full power and you'll get 146v out of the driver maybe a touch more.

VegasWinner said:

I used 4-cxb3590 36v cobs with a C1400B driver for 200w and 50w per cob. Going with 75w per cobs and 225 watts max with three cobs will be inefficient and hotter. The idea is to generate light without generating unnecessary heat. The higher wattage you run cobs the more heat the generate and the less usable light they generate. You can make your cobs blinding bright, but that does not mean that is the best light. Half of ALL light is unseen to the naked human eye. Plants use that light we can not see more efficiently than the light we do see.

I retired cobs this year as newer technology has arrived that makes cobs less effective than the current mid-power diodes from Samsung. Cree and Osram have joined forces to compete with Samsung a Korean/Japanese JV in the mid power horticulture area.

I now use Samsung diodes mounted on my own boards similar to ChilLED grow lights commercial;y available and parts and ;lights available to the public as well. I paterned my light engine after Vitaly's of ChilLed Grow Lights because I have studying him for a few years and now he has stepped out from the pack and show his lights are top notch, and not cheap either, but his light engines are affordable for DIY.

Click to expand...

Going with 75w per cob won't be "inefficient". It will be slightly less efficient than running them at 50w per cob. Also, plenty of growers would rather use fewer cobs and higher amperage because it saves you a fair bit of money on your setup costs. Also, 500w of cob is going to generate almost identical amounts of heat regardless of whether there is 1 cob or 10 cobs. Not everybody has the same outlook or expectations for their grow as you do. They need to balance their own needs, growing style and budget then build accordingly.

Just ignore vegaswiner and his imaginary "knowledge". I mean "Plants use light we can not see more efficiently", seriously? Does the nonsense never end?

COBs are not less effective than anything else either. It's a price and convenience choice. If anything, I'd say led boards are a lesser choice. I prefer leds strips if you insist on using SMDs and get much better light uniformity than with boards. Or simply COBs. Great light distribution too, if you don't run them too hard.

When you use that Cree tool, make sure you change the temperature to 50 or 60C. 25C is completely unrealistic. At higher temperatures, the voltage and wattage drops slightly and you will be well within even the basic limits. Besides, if you look a bit down in the datasheet the over voltage protection only kicks in around 150V~165V.

1750mA (61.5W) is a good choice for a CXB3590. Maybe also look into Citizen COBs, they are a fair bit cheaper and good quality just like Cree.

wietefras said:

When you use that Cree tool, make sure you change the temperature to 50 or 60C. 25C is completely unrealistic. At higher temperatures, the voltage and wattage drops slightly and you will be well within even the basic limits. Besides, if you look a bit down in the datasheet the over voltage protection only kicks in around 150V~165V.

Click to expand...

I was pretty sure that forward voltage went down at higher temps. It does, by about 0.4v each, going from 25C to 50C.
I am guessing it will work, as long as the initial room temperature is closer to cool/warm. than to freezing. The other thread mentioned earlier indicates that the COBs will light. I will grab one, and verify that it works, and that it draws 1.75A, before ordering more over time.

For a 4x4 (ish) future area, I was deciding whether to run 4 bars @ 1.4A, (800 watts total) or 3 @ 1.75A (750 watts total). I am willing to trade off a little efficiency to hang the lights higher. In hand, I have one HLG-320H-C1750A that I picked up, and it is in a current small grow, replacing a 1.4A source. I have a cheap analog current meter in line with the DC. They are spendy and heavy though. (and only partial dimming), thus the interest in the 240H-1750B.

Taos said:

Hi,
I was looking at the Mean Well HLG-240H-C1750 on RapidLED for driving 4 Cree 3590's at 1750ma.

The Rapid web site suggests using this driver with 2-3 36v COBs.

I used a Cree online tool, and determined that at 1750 ma, the COBS are likely to have a voltage drop for 35.5 Volts. So 4 of these would total 142 volts. The spec sheet for the driver indicates that the driver is constant current up to 143 volts.

To me, it looks like it will work. (142 < 143) Am I missing something, or is this some sort of error at Rapid? (If the COB had an _actual_ voltage drop for 36 volts, the total would be 144, which would be 1 volt too high.)

Thanks for any input!

Click to expand...

I own an early TastyLED T4-1750 lamp which has the same components that you are looking at. It's a perfect fit.

It works. I've ran 2 separate 4series cxb3590's on those drivers.

Danielson999 said:

When cobs turn on their vf is higher because they are cold which would mean your total volts would likely be higher than 143. You could cap the dimming wires on a 'B' version of the driver and run them at full power and you'll get 146v out of the driver maybe a touch more.



Going with 75w per cob won't be "inefficient". It will be slightly less efficient than running them at 50w per cob. Also, plenty of growers would rather use fewer cobs and higher amperage because it saves you a fair bit of money on your setup costs. Also, 500w of cob is going to generate almost identical amounts of heat regardless of whether there is 1 cob or 10 cobs. Not everybody has the same outlook or expectations for their grow as you do. They need to balance their own needs, growing style and budget then build accordingly.

Click to expand...

Both mean the same less efficient or inefficient. cxb3590 runs most efficient between 35w to 50w above more heat less light in the specs. What others do is not the point. If everyone else jumped off the roof you jumping too?
If you are going to take the time to design and build an led light don't short change yourself or build s cheap light. Do something else save your money instead of wasting it. Good engineering discipline.

I've got 3 panels each with 4 x CXB3590's 36v on these drivers. So far no issues. I normally run them at between 30-40w per cob. I do keep a small fan on the drivers to keep them cool.

VegasWinner said:

Both mean the same less efficient or inefficient. cxb3590 runs most efficient between 35w to 50w above more heat less light in the specs.

Click to expand...

It's all about return on investment. It depends what you pay for electricity, but for most people around 2.3umol/s/W to 2.4umol/s/W tends to be the sweet spot for Cree. If you run them softer to get higher efficiency you pay extra on the fixture and you will not recover that within a reasonable time span with the savings on your electricity bill. Alternatively, if you run them harder, you will need less COBs and therefore have a cheaper fixture (initial investment), but you will incur higher running costs since you will use more electricity. In the end you will pay more extra on your electric bill than what you saved on the fixture.

You could calculate what is the optimal efficiency for your situation.

In my case it's around that 2.3umol/s/W to 2.4umol/s/W range. So a CXB3070 I run at 1400mA (48W) and a CXB3590 at 1750ma (61.5W)

If you run the CXB3590 at 50W and compare that to the CXB3070 at 50W, you will pay 50% per COB extra for the CXB3590 and you will save only 6% on your electric bill. It would take a few years of pretty much non stop flowering to earn back that extra investment.

Going down to 35W is really nonsense with a CXB3590. That only makes sense in a highly specific scenario when you are very limited on electric power use. Suppose you can use only a few hundred watts and you want to get maximum light from that limited amount. Only that would make sense to pay for almost doubling the number of COBs needed.

So yeah, better not waste money, but that specifically also means not to go overboard on efficiency.

VegasWinner said:

Both mean the same less efficient or inefficient. cxb3590 runs most efficient between 35w to 50w above more heat less light in the specs.

Click to expand...

1.75A = 169 Lumans/Watt (bin DB @50C)
1.4A = 178 Lumans/Watt (bin DB @50C) (2.3-ish umoles/joule ??

I am guessing that they are even more efficient at 1A, and even more so at 0.7A, and probably even more so at 0.001A Right now, I want 30K lux (I don't have a umol meter) for veg, and get it over a 2'x4' with 8 cobs at 1.4A @3 feet height, as measured by the "cheap Lux Meter", available everywhere. later I will want 50-ish k lux, achievable by lowering the distance, or by consuming more power.

I am extremely content with these numbers (1.4-1.75), and have the ability to turn my lights to 11, at an efficiency cost of approx 5%. When I change 2 4-cob panels over a 2x4, to 3 4-cob panels over a 4x4, I will want in increase in power to obtain the same lux in the area, with less cobs per square foot. 5% in extra energy costs is very appropriate to continue using the equipment I already own!

Just to totally geek out, I have also an efficiency gain of 8% from bin DB, when compared to bin CD. I do care about efficiency: I just bought my first Hyper Fan, which runs on full at approx 50 watts. I run it at about 20 watts and move the same air as my 4" HTG fan which uses about 100 watts. Huge savings. I have 2 pair of powered speakers, which run class A or class AB and consume 30 watts each when there is no audio input. They are on a switch now. I hate to tell you what my lead/acid computer battery backup consumed before it was disposed of at a church event.

I do get that Samsung (318C?) LEDs are even more efficient than CREE cobs. I am very happy where I am at for now and the immediate future.

I know I have some of those DB bin below 50w it does not improve by much which is why it is a good target. When you dim a 50w to 25w you can gain some efficiency but it is not linear. About 35w is the minimum.

@Taos, Exactly. You can keep going lower and gain efficiency. The efficiency gain going from 61.5W to 35W is similar to going from 50W to 25W.

The problem is that the price goes up too. Quite fast since you need to buy much more COBs to get the same amount of light. At some point you just start paying too much for the extra COBs in to offset the small benefit you get in electricity savings. Just see what your optimum is and go with that. If you have an expensive kWh price going lower is more beneficial and if you pay less per kWh then you can run them harder.

There is no case of some leds being more efficient than others or than COBs. You can pick the efficiency yourself (to some extent). It's the price at which you can achieve this efficiency which matters. Citizen COBs get the same 169lm/W to 178lm/W efficiency you get from the Cree's, but at about half the cost for the COBs.

BTW It's funny how vegaswiner is banging on about using low wattage for Cree COBs and then he tells people that the boards he's selling can be run at 230W. While they are designed to be run at 190W. His boards at 190W are actually already less efficient than a Cree CXB3590 running at 61.5W. Go to 230W and it would be comparable in efficiency to a CXB3590 running at 75W.

wietefras said:

@Taos, Exactly. You can keep going lower and gain efficiency. The efficiency gain going from 61.5W to 35W is similar to going from 50W to 25W.

The problem is that the price goes up too. Quite fast since you need to buy much more COBs to get the same amount of light. At some point you just start paying too much for the extra COBs in to offset the small benefit you get in electricity savings. Just see what your optimum is and go with that. If you have an expensive kWh price going lower is more beneficial and if you pay less per kWh then you can run them harder.

There is no case of some leds being more efficient than others or than COBs. You can pick the efficiency yourself (to some extent). It's the price at which you can achieve this efficiency which matters. Citizen COBs get the same 169lm/W to 178lm/W efficiency you get from the Cree's, but at about half the cost for the COBs.

BTW It's funny how vegaswiner is banging on about using low wattage for Cree COBs and then he tells people that the boards he's selling can be run at 230W. While they are designed to be run at 190W. His boards at 190W are actually already less efficient than a Cree CXB3590 running at 61.5W. Go to 230W and it would be comparable in efficiency to a CXB3590 running at 75W.

Click to expand...

I don't sell boards I give best advice for each person not funny genuine. OP focus is on COBs I do my best to share fairly. I have no preference since I don't sell lights I help people build their own light.

wietefras said:

@Taos, Exactly. You can keep going lower and gain efficiency. The efficiency gain going from 61.5W to 35W is similar to going from 50W to 25W.

The problem is that the price goes up too. Quite fast since you need to buy much more COBs to get the same amount of light. At some point you just start paying too much for the extra COBs in to offset the small benefit you get in electricity savings. Just see what your optimum is and go with that. If you have an expensive kWh price going lower is more beneficial and if you pay less per kWh then you can run them harder.

There is no case of some leds being more efficient than others or than COBs. You can pick the efficiency yourself (to some extent). It's the price at which you can achieve this efficiency which matters. Citizen COBs get the same 169lm/W to 178lm/W efficiency you get from the Cree's, but at about half the cost for the COBs.

BTW It's funny how vegaswiner is banging on about using low wattage for Cree COBs and then he tells people that the boards he's selling can be run at 230W. While they are designed to be run at 190W. His boards at 190W are actually already less efficient than a Cree CXB3590 running at 61.5W. Go to 230W and it would be comparable in efficiency to a CXB3590 running at 75W.

Click to expand...

The board will not draw more amps than it is designed for. Driving individual diodes at maximum efficiency while getting excellent power pay attention

Taos said:

I was pretty sure that forward voltage went down at higher temps. It does, by about 0.4v each, going from 25C to 50C.
I am guessing it will work, as long as the initial room temperature is closer to cool/warm. than to freezing. The other thread mentioned earlier indicates that the COBs will light. I will grab one, and verify that it works, and that it draws 1.75A, before ordering more over time.

For a 4x4 (ish) future area, I was deciding whether to run 4 bars @ 1.4A, (800 watts total) or 3 @ 1.75A (750 watts total). I am willing to trade off a little efficiency to hang the lights higher. In hand, I have one HLG-320H-C1750A that I picked up, and it is in a current small grow, replacing a 1.4A source. I have a cheap analog current meter in line with the DC. They are spendy and heavy though. (and only partial dimming), thus the interest in the 240H-1750B.

Click to expand...

You should leave out talking about me on someone elses thread people are tired of your off topic personal swipes. I ignored you but people are tired of your personal attacks that have nothing to do with the topic at hand.

VegasWinner said:

The board will not draw more amps than it is designed for. Driving individual diodes at maximum efficiency while getting excellent power pay attention

Click to expand...

Come man, even you should understand that that is complete nonsense:
A) "Maximum efficiency" would be at the point where the led just lights up fully. That's nowhere near what you are running those SMDs at.
B) Efficiency is determined by watts not by current alone.

The fact remains, even if the best case scenario datasheet figures apply then at 190W those boards are running at an efficiency level comparable with a CXB3590 at 61.5W. Running the board at 230W it's efficiency is comparable to a CXB3590 at 75W. It's still a question mark if your boards even reach that efficiency though since you don't have them tested.

You can play the sad little victim all you want again, but it's a perfectly legitimate remark to point out that you keep pressuring Taos into running the COBs at low wattages to get an unnecessarily high efficiency while you yourself aren't doing that with your own boards.

I did not want to bring this up on someone else's thread. I did the math on my thread. I will repeat it here.
The amp draw is 1.81amps
watts draw 209 watts
volts draw 116v
If you do the math for a 32s6p circuit with two channels you will discover the draw per channel is 150.88mA per parallel string for six strings times two channels giving 1.81a. 1.81/2 = 0.905/6 = 150.88mA per string which is per diode driving the LM561C at the sweet spot.
Now with 32 diodes per string there are a total of 12 strings in two channels giving 384 diodes driven at the sweet spot most efficient less heat highest lumen ouput second only to a chilLED board exceeding all others by design and physical components. This is accomplished using a C1050A/B driver lower current draw than the "other" boards or even COBs driven with big drivers including C1040A/B drivers and above.
So the GrowGreen board was designed to run at optimum current lower amp driver highly efficient driver and high lumen output.
If you want to dispute the facts. Join the coop get a couple boards send them off for sphere testing and tell me what I already know 2.5um/j easily better than most other boards
Thanks for letting me share the technical specs on the GrowGreen board 200w 3000k/5000k and 3500k/5000k board spectrum with more options available. It is up to the coop members to decide
Peace