New RA owner here, trying to hook up 2 LED fixtures with a total of 4 Meanwell ELN-60-48D drivers (2 drivers per fixture, 1 for whites, 1 for blues). This is going to be long, so please bare with me.
I got a PWM expansion module, but have not hooked it up yet. I did all my testing using the 2 PWM channels that come with the main relay box. I also received a pair of PWM-to-Analog Lead wires with my controller. Once I get the PWM expansion module configured, I'll try to test again with that to see if I get different results than I did with the 2 stock channels.
First thing I did was test my lights using a 9v battery as a "dimming signal". The battery was at 9.4V as per my multimeter. All lights were very bright and I tested whites and blues for each fixture.
Next, using the Demo code on the controller, I went into PWM settings and made 1 channel 100%, the other channel 50%. Then, to verify the signal strength, I took multimeter readings right at the pins on the relay box. The 100% = 9.77V, the 50%= 4.94V.
Next step, I connected the PWM-to-Analog leads to the pins and took a reading on the open wire ends. The 100% = 3.17V, 50% = 1.86V. That's a pretty big dropoff between the pins and the other end of the converter! It seems it lost about 68% voltage on the 100% channel, and about 62% voltage on the 50% channel.
*LED FIXTURE INFO* - Dimming control is via an ethernet port on the fixture. I had to use a CAT5 patch cable to plug into the port, then cut/strip the other end to get bare wires. This is how I tested with the battery and verified the +/- wires for each channel.
Next step, I connected one driver's dimming wires to each converter. Lights worked for both channels, however, they appeared much dimmer than when I tested with the battery, even the 100% channel.
I then removed the ethernet plugs from the fixture ports, and tested the voltage at those pins. Voltage readings were the same as what I got at the end of the converter... so the patch cables were good.
Next test was to determine when the lights would shut off. I ramped the controllers PWM signals down in increments of 5 and then pinpointed the actual shutoff value was 21% intensity. At 22%, lights were all fine, at 21%, each channel (blue or white) shutoff. So a single ELN-60-48D driver on a single channel cutoff at 21% intensity when using the converter.
Next, I combined both drivers onto 1 channel. I twisted both blues and whites onto 1 converter. The results were basically identical... shutting off both at 21% intensity.
Next, I brought out fixture #2 and made another patch cable. I jumped right into adding all 4 drivers (2 from each fixture) onto 1 converter. This time, the results got worse. I started at 50% (thinking I'd work my way down) but none of the lights even came on. So I jumped up to 75% and worked down to 59%, where the blues went out on 1 fixture. At 58%, all lights shut off.
The last test was sort of irrelevant since I plan to only have 1 driver per channel... but I did it for the data and to satisfy my curiosity anyway.
So, being upset that I wasn't going to be able to utilize my new LEDs to the fullest extent, I remembered reading this thread and decided to see if my lights would work with a straight PWM signal, instead of using the converter.
I dug out my old box of computer parts and found a fan that had a 2-pin connector. (See, I knew I was going to need that someday!) I cut the wires off of it and I now had my lead wires without a PWM-to-Analog converter. Just a black and red wire.
OK, first test was setting the controller back to 100% channel and 50% channel. Took readings at the pins and got the same results as first time. 9.77V and 4.94V respectively.
Then I connected to the 100% pins and got 9.74V at the bare wires. Very minor dropoff, but I can live with that. I moved the connector to the 50% and got 4.91V at the bare wires. Again, acceptable IMO.
Next step, I wired 1 set of wires from the patch cable to these wires. I took readings at the ethernet jack pins and got the same as at the wired connection. Just double-checking that everything is still good.
Now, I was a bit scared of damaging either the fixture or the controller, so I did this set of test starting with 0% intensity and worked my way up to find out when the lights would turn on.
With a single driver on a single channel, lights came on at 10% intensity (PWM signal set on controller).
Seeing that was an improvement, I then added the other driver to the same channel. Again, starting at 0%, both whites and blues came on at 10% intensity. Voltage readings at the twisted wires was almost identical, maybe a few points lower.
After that, I got brave and added all 4 drivers to the same channel. Guess what, 10% was still the turnon point for all 4 drivers!
Next, I kept all 4 on the same channel, and ramped them up in 5% increments. I could barely notice the brightness increasing with each step with my eye, so can't comment on the scaling aspect. But, all lights ran continuously, no flickering or anything. And, at 100%, they were way brighter than when I had the in-line converter wired in. In fact, at around 50% they looked brighter to me than 100% with the converter!
I got all the way to 100% with 4 drivers, 1 PWM channel, and then took a reading at the wired connection to the new (non-converted) lead wires. I got 9.68V @ 100% intensity. A slightly higher dropoff than with a single driver one a single channel, but certainly one that most people could live with.
So, seeing that these seem to operate perfectly fine, my only other worry is whether the PWM signal will damage the driver. I put the lights away and didn't run them this way any longer. Roberto says he talked to people at Meanwell and it won't hurt the drivers to do this, so that's a glimmer of hope.
But, the main reason I posted this was to give data showing the PWM-to-Analog lead wires are not working as intended (or at least not to my expectations.) They do allow an analog driver to work, but at a very minimum capacity compared to their optimum performance.
I think my 3 x 3w moonlights, running on a constant current 1x3w driver was brighter than the 33 x 3W royal blue / UV mix running at around 2W each actinics.
Roberto, I'm the one that linked you this post in an email this morning. (Well, I'm about to do that right after I hit submit. Do you think you can take a look at the converters and test the voltage on the wires to verify my findings? Maybe the wrong resistor/capacitors were used to make these converters?