DiY LEDs - How to Power Them

REALSTYLES

Well-Known Member
Bill, you need to forget about the Vf. You don't really have control over that with the drivers we use. Most of us use full Constant Current drivers ( hlg185h-c2100b or similar) and the only reason you need to know Vf is to see how many COB will fit on a given driver.
The driver you are referring to is also a Constant Current driver ( hlg185h-48b or similar), but it has a voltage limit (48v) and will run CC 3.9Amps until you draw 48v then it converts to a CV and limits it at 48v. The hlg185-42 will run CC @ 4.4 amps and the hlg185-36 will run CC @ 5.2 amps. If you run the 36 volt, then the driver will limit you to 36v. If you buy the A version, then you can adjust the drivers voltage out between 33v and 40v.
Now when you do use a CC/CV driver you can add as many COBs as you want, but you must run in parallel to maintain the voltage.
The CC drivers your running in series and the driver will only give the set amperage to each and every COB until you run out of volts out.
didn't you burn up some cobs running them parallel? Due too voltage droop?
 

nevergoodenuf

Well-Known Member
I have never had an issue running in parallel. I have run Vero29s on a CEN-100 with everything from 1 to 4. I have also ran different temps in the same parallel circuit. Never an issue.
 

nevergoodenuf

Well-Known Member
If you look at the data sheet were it says amps for that voltage. That is how many amps you will have total being split up. The A version also has a pot and a voltage range that can be adjusted around that voltage. If you use a 48, you get less amps to split up than with a 42v version, but the 36v might not be enough unless you get the A to allow you to turn up max voltage. I hope this helps.
 

OLD MOTHER SATIVA

Well-Known Member
BG Micro a Texas electronics surplus dealer is currently selling the following Mean Well LED drivers:
HLG-120H-48A LED Series Power Supply, 48V/2.5A With Connectors
PWR1427 $14.95
0.1245$/w
http://www.bgmicro.com/hlg-185h-48a...-current-high-efficiency-by-meanwell-1-1.aspx


>>hi I ordered 10 of these

will i have to manually adjust for say ..36 v 3590's

**i have a multi meter..will the driver have to be connected to ac or just use a probe on the in and out**

i want to run 3 per driver..hydro is more like 26 cents a kwh here

thanks
 

Bill Lidgate

Active Member
HLG-185H-48A LED Series Power Supply, 48V/3.9A With Wires Stripped And Tinned
PWR1424 $22.95
0.1240$/w
http://www.bgmicro.com/hlg-185h-48a-led-series-power-supply-48v-3-9a-constant-current-high-efficiency-by-meanwell.aspx
I just received 20 of the HLG-185H's in original packing. These were part of an order of maybe 400-1000 Units shipped straight from Mean Well to Future Electronics in Southaven, MS they are likely recouping their wholesale cost at this volume. BG Micro will drive the 1h from Garland TX and pick these up until they are all sold, representing quite a good deal.
 

Bill Lidgate

Active Member
Here is another power supply bargain: a 300w supply for $29 ($0.0967 per watt!) IP67, PFC, 94% efficient, etc. made by a good company
http://www.allelectronics.com/make-a-store/item/ps-1028/28-vdc-10.71a-power-supply-led-driver/1.html
they have 50+ units and will do free shipping if you buy enough,
note these are constant voltage (CV) and not nearly as flexible as CC/CV units like the Mean Well HLG series,
they put out 28VDC at 10.7A and that's it, no dimming, no trimming!
spec sheet here:
http://www.trpssl.com/driver_spec_sheets/TRV-300.pdf

here is a compact little flame thrower I am prototyping with one
 
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Airwalker16

Well-Known Member
Here is another power supply bargain: a 300w supply for $29 ($0.0967 per watt!) IP67, PFC, 94% efficient, etc. made by a good company
http://www.allelectronics.com/make-a-store/item/ps-1028/28-vdc-10.71a-power-supply-led-driver/1.html
they have 50+ units and will do free shipping if you buy enough,
note these are constant voltage (CV) and not nearly as flexible as CC/CV units like the Mean Well HLG series,
they put out 28VDC at 10.7A and that's it, no dimming, no trimming!
spec sheet here:
http://www.trpssl.com/driver_spec_sheets/TRV-300.pdf
HLG-###H-C series are the flexible ones.
 

Bill Lidgate

Active Member
BG Micro a Texas electronics surplus dealer is currently selling the following Mean Well LED drivers:
HLG-120H-48A LED Series Power Supply, 48V/2.5A With Connectors
PWR1427 $14.95
0.1245$/w
http://www.bgmicro.com/hlg-185h-48a...-current-high-efficiency-by-meanwell-1-1.aspx


>>hi I ordered 10 of these
will i have to manually adjust for say ..36 v 3590's
**i have a multi meter..will the driver have to be connected to ac or just use a probe on the in and out**
i want to run 3 per driver..hydro is more like 26 cents a kwh here
thanks
the Cree CXA3590 runs at about 1.4A at 36V. 1.4 x 36 = 50W so 3 in parallel would draw 150W which is about 80% of the HLG-185H's capacity (80% is a good rule of
thumb).

As an aside, most electrical engineers would recommend running series resistors off each LEDs negative terminal to balance them (in this case 1 Ohm / 5w would do) like this:



see: http://led.linear1.org/led.wiz

Many omit these resistors, trading wear and tear on the COBs for saving the 6W of power wasted on the resistors, and the $3 they'd cost.
 
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guod

Well-Known Member
most electrical engineers laughing about this circuit.
voltage drop over the resitors 1.4A x 1Ohm = 1.4V
voltage over the diodes now 34.6V and at this voltage there is no current flow of 1.4A
conclusion : we need higher source voltage
what a stupid wizard
 

JorgeGonzales

Well-Known Member
most electrical engineers laughing about this circuit.
voltage drop over the resitors 1.4A x 1Ohm = 1.4V
voltage over the diodes now 34.6V and at this voltage there is no current flow of 1.4A
conclusion : we need higher source voltage
what a stupid wizard
I don't understand why you would need added resistance at all. It's a CV driver, so what "wear and tear" would there be on the COBs? Some would run a few ma more or less, but they'd all be happy.

I've never used this series of Meanwell though, so maybe I'm not fully grokking how it works. Take the HLG-185H

image.jpg


So at 4.2A lets say. Constant Current Region is 21-42V, what does that mean exactly, when it's a 42V driver. What happens when you put a 36V cob on there, or two in parallel? Two 36V cobs at 2.2A each would be about 158W, so is that how the driver behaves?

Or do you just get one 36V cob held at a constant 4.4A and that's it.
 
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OLD MOTHER SATIVA

Well-Known Member
thanks BILL

I plan to use 3 or 4 nichia j130b cobs in parallel so they are using around 40[38?] w

that is if i can ever find a holder for them..[yes i have more than few emails out to companies]

3 x 3590's would draw 50w even though its 120 w driver..is it the differerential between 36 v and 48 that allows for more w than the driver is?

yes i will run everything in parallel..well until i understand series..in relation to cobs..

but for sure..there will be no resistors done by me..
 
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