Cxb3590 36v vs 72v pros and cons?

Getgrowingson

Well-Known Member
I am looking into ordering some cobs from kingbrite. I want to power each cob at ~50w. 4 per bar with three total to cover a 4x4 to 5x5 area. So 600w or so. I can get them at the same price. Which would you choose if you had a choice? Any pros cons you can come up with? Lower voltage drivers obviously but other then that is there anything to be gained by going with either one? Any comments welcome!
 

churchhaze

Well-Known Member
The 36V version would allow you to put more in series for a given voltage.

the 72V version would draw less current per string.

If you wanted to use the HLG-185-Cxxx, you'd likely use the C1400 (143 for the 36V version and the C700 (300V) for the 72V version.
 

mc130p

Well-Known Member
Resistive heat losses grow with the square of the current, so imho, I like to stay with 72V if I can... I can understand some people want the 32V for the reason Church listed though.
 

Getgrowingson

Well-Known Member
The 72V version has twice as many leds per string, but half the parallel strings.

The 36V version has half the leds per string, but twice as many parallel strings.
Your talking about the LEDs inside of each cob in this post correct? If you were building this light which would you roll with? I suppose it doesn't matter much really because it will draw the same wattage either way. Unless drivers are cheaper for a lower current which I don't think is the case.
 

churchhaze

Well-Known Member
Your talking about the LEDs inside of each cob in this post correct? If you were building this light which would you roll with? I suppose it doesn't matter much really because it will draw the same wattage either way. Unless drivers are cheaper for a lower current which I don't think is the case.
Yes, I mean the individual leds as they're routed on the cob.

Given the selection of currently available drivers, the 72V version is probably better assuming you feel safe working with 285-400VDC.

If we had a hypothetical new 400W drivers that were both 285V and 1400mA, then the 36V version would begin to really shine.
 

Getgrowingson

Well-Known Member
Yes, I mean the individual leds as they're routed on the cob.

Given the selection of currently available drivers, the 72V version is probably better assuming you feel safe working with 300-400VDC.

If we had a hypothetical new 400W drivers that were both 300V and 1400mA, then the 36V version would begin to really shine.
Gotcha thanks bro. I work with 400kv for my career so am totally comfortable. Need to respect voltage and current. Will end your life quickly given the right circumstances
 

Getgrowingson

Well-Known Member
Yes, I mean the individual leds as they're routed on the cob.

Given the selection of currently available drivers, the 72V version is probably better assuming you feel safe working with 285-400VDC.

If we had a hypothetical new 400W drivers that were both 285V and 1400mA, then the 36V version would begin to really shine.
Is there any drivers currently available that output 1050ma at 285v? All I can find is the hlg185-1050c and it seems it only goes up to 190v which seems to me I can only run 2 off of one driver which will cost me a small fortune in drivers. Also if I go the 700ma and want to out 4 on one driver simple math says I need 288v when the hlg185-700c maxes out at 286. Which seems to totally suck haha
 

churchhaze

Well-Known Member
Is there any drivers currently available that output 1050ma at 285v? All I can find is the hlg185-1050c and it seems it only goes up to 190v which seems to me I can only run 2 off of one driver which will cost me a small fortune in drivers. Also if I go the 700ma and want to out 4 on one driver simple math says I need 288v when the hlg185-700c maxes out at 286. Which seems to totally suck haha
Now you know our pain.. lol. there are so many almost perfect combinations, like 4x vero 29 on a hlg-185-1400 is short by a volt or 2.

Either way, I don't think 4 of them would actually add up to 288V at 700mA. I think that at 700mA, the forward voltage is less than 72V.
 
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bicit

Well-Known Member
Is there any drivers currently available that output 1050ma at 285v? All I can find is the hlg185-1050c and it seems it only goes up to 190v which seems to me I can only run 2 off of one driver which will cost me a small fortune in drivers. Also if I go the 700ma and want to out 4 on one driver simple math says I need 288v when the hlg185-700c maxes out at 286. Which seems to totally suck haha
Should actually be around 71v. I'll test and see if 4 will fit on an HLG-185H-C700 later this afternoon. I just happen to have that exact combo :P
 

bicit

Well-Known Member
Did you ever end up giving this a shot?
Yes, sorry about the delay. Didn't have time to sit down and test. However I finally got a chance. the HLG-185H-C700 is capable of running 4, 72v CXB3590's no problem. The HLG-120H-C1050 was able to run two with no problems as well.
 
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