Meanwell LDD 48v in Zero Out

pjhaddock

New member
Hi all. I just swapped my 24V Steve's LED drivers to 48V and Meanwell LDD drivers. I had 7 LED's on each string so I combined matching strings to 14 each. I hooked everything up and have the Meanwell LRS-350-48 power supply set to 48v to start. I can measure 48v going in to each LDD, but 0v coming out of all of them and no lights. I know the LED's are wired correctly and have no shorts, they worked before swapping them out and I retested everything. Any ideas? The wires for the PWM aren't hooked to anything on the other end at the moment to rule that out. I'm lost. Thanks for any ideas!

Here are a couple pics. Hopefully everyone can access them.
https://photos.app.goo.gl/7Zs1Un1kPyo9ERpt8
 
Do you have the LDD's on a board w/ a pull down resistor??
sounds like it..
You NEED a signal at the PWM wire or it won't light..
A Lithium button cell will work (about 4V).. pos to the PWM wire.. neg to DC
negative on the power supply.
At least that's how I remember it..

POINT is w/ the resistor you can't "float" the PWM wire..

Don't blow yourself up.

Or use a 5V phone charger.. same pattern, or just hook up your controller..
Cheap plug for RapidLED's board w/ removable pull down's via jumper..;)

Pull down resistor comes pre-installed, this keeps the lights from flashing during power on/off.
Also keeps them from lighting..
48v is "normal" where you measured it. you will see zero v (approx) at the other end of the ldd.

Which is why the drivers aren't "firing".. BTW a bit confused on the green/white connection to the board.. Explain please..
 
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Here is the board.
https://www.stevesleds.com/LDD-Driver-Array--8X-Drivers_p_306.html
You were correct. I hooked my Bluefish controller up and everything fired right up. Thanks for that. I have the APEX VDM and this controller Interface
https://www.stevesleds.com/Aquarium-Controller-Interface-Harness_p_183.html
And it will not output the 5v pwm. I even ordered a 2nd one assuming it was bad and same thing. I can measure 0-10v in and watch it increase as I ramp up the channel, but output is nothing. Everything shares a common ground and has continuity. The interface is powered by a separate 12v supply but shares a ground. So frustrating. Thanks again!
 
And it will not output the 5v pwm. I even ordered a 2nd one assuming it was bad and same thing. I can measure 0-10v in and watch it increase as I ramp up the channel, but output is nothing. Everything shares a common ground and has continuity. The interface is powered by a separate 12v supply but shares a ground. So frustrating. Thanks again!

What is the current rating of the 12V supply?
Maybe not enough current.. Unlikely but??
didn't see any specs on this..

So the 10V to 5PWM board has one "ground" plug where you common the power supply and 12v source.
NOTE:
Do not connect to main LED power supply
using the +5V port
, you must use port “Vin”
for any voltage higher than 5.0V
.
There is a 5V source (+) next to it but separate..


Is the blue led on?

Actually it looks like you have the + and minus reversed but that would be bad..
 
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His newest board doesn't have separate 5v and vin connectors and they have continuity so not separate inputs. Just Vin which will take any input from 5v to 35v. It is a big supply, if I remember right it was like 2-3A. It is mounted in the hood and powers my fans. I did try another 12v 800ma supply just to test as well. The grounds between both power supply DC-, ldd board, and controller interface all have continuity so good there and yes the blue LED is on. It would be hard to believe that I got two bad controller interface boards, but I don't know what else it could be? In talking with him, he says that they are tested before they are mailed. Think is it possible that even though I can measure the 0-10v out of the Apex vdm, that it is bad? I did try hooking up my 3v LED tester (2AA batteries) to the input on one of the channels of the controller interface to simulate 3v and nothing happened so likely not. Thanks for helping out!
Here is a separate pic of the interface board.
https://photos.app.goo.gl/eGTLyqtRrum5Gjb46
 
I got nothing..
Maybe you reversed the "port" assignment..
o-10v should be on th +/- side of the board..
 
I got nothing..
Maybe you reversed the "port" assignment..
o-10v should be on th +/- side of the board..
Yeah same here. The input side has +/- which takes the 8 wires from the APEX. The PWM out is just 1 wire for each channel. I'm at a loss. Guess I can continue to use my Bluefish LED controller and send the APEX VDM back but not really what I want to do. I see other people with the ACI from Steves hooked to an APEX working. :headwally: lol
 
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