Question about driver and voltage

I want to use 5x vero29C SE driven at 700ma to give me a total of 238W since they use 68.1 volt each.

I want to use a meanwell hlg 240 to power them but I don't know which one to chose.

I read somewhere that the driver needs as much voltage as the cobs need. So 68.1x5=340.5V in my case.

The HLG-240H-C700A has an output voltage of 351 so I have enough right?

Also which model do I need if I want a dimmer and what kind of dimmer do I need?

Thanks in advance guys.

Hey newguy123. I built one recently using vero29 SE C bin COBs @ 90 CRI 3000K. I used an HLG-480H-C1400B. Those COBs are rated for an operating drive of 1710 mA with a max of 2100 mA, so I would recommend using 1400 mA. That driver totals 469.7 W on 5 of those Vero29s @ 1400 mA.

The B driver is the one you can attach your own potentiometer to for dimming. I used these potentiometers: https://www.amazon.com/gp/product/B01LZ74KU3/ref=oh_aui_detailpage_o09_s01?ie=UTF8&psc=1. Wire the COBs in series. I would recommend testing the potentiometers with a voltmeter to make sure they are 100K Ohm or above. You will find a mix in the bag, some will be above, some below. If it is below 100K, you may need a resistor to make up the difference. Otherwise you will not get 100% power out of the COBs.

If you use the A driver, it has a small potentiometer built in, but you have to use a screw driver to adjust it.

I recommend using active cooling as well. I mounted my COBs to Arctic Alpine 64 Plus CPU coolers with some Arctic Silver 4 thermal paste. They are all driven off a single Mean Well APV-16-12 12V 1.2A driver.

As a side note, the active cooling is AWESOME. I can touch the heatsinks while the light is on and has been on for 12 hours and it is cool to the touch.

where did you see the operating drive of 1710ma?
That would mean it would have a minimum wattage of 118.7.

https://www.bridgelux.com/sites/default/files/product_selection_guide/PSG-120 Vero SE Selection Guide 20171215 Rev. D.pdf

Page 14, next to last entry.

Why would you recommend a current of 1400? I can drive them at 700 and get a much better efficiency according to the data sheet.

A car can get great gas mileage if you keep it at 30 MPH, but you are paying for a LOT more car than that.... same with a custom build like this. It will be super efficient, but you won't get nearly the lumens at 700 mA.

At 700 mA, you will be throwing out about 7338 lm per COB, with a total of 36,690 lm. At 1400 mA, you are throwing out 13,239 lm per COB, totaling 66,195 lm. It's a vast increase in light output with very little drop-off on return. Once you go above 1400 mA, it starts to drop off a lot more.

Cost breakdown:

Fans: $60 (5x $12 on Amazon)
Wire: $17
Thermal Paste: $6
Power Cord: $11
Aluminium L Frame: $40
Cobs: $144
Fan Driver: $9
Potentiometers: $10

700 mA LED Driver: $57.80
1400 mA LED Driver: $138

700 mA Total: $354.80
1400 mA Total: $435

@700 mA: 103.41 lumens per dollar
@1400 mA: 152.17 lumens per dollar

Again, this is just my suggestion. Do what works for you. You may not need that much light.

Your suggestion is the best bang for buck and if it was my most important criteria, I would be a fool to do otherwise.

Sadly I am limited by the amount of power I can use. So I have to get the most efficient and affordable setup I can find which I believe to be the one I posted.

Awesome, share some pics when you're done so we can see the final product.