LEDgardener

Hey everyone,

So I learned how to use a multimeter with the help of LEDG video and I realized I had made a big mistake in my planing. I bought 4 132's and an HLG-240H-1750A thinking I would be able to use the driver to pump out 1950mA to the boards. Well, when I hooked up the multimeter I was only at 1.57A and 35.7V, for a total of 224W. This doesn't seem to be enough for a 3x3 space. I missed the very important fact that the driver maxes at 143V and I need 144V to run each board at 36V.

This is a bummer. It reduces my power by a great deal. I looked into drivers that would give me the power I need and ran across the Meanwell LRS-350-36, which seems to have enough power to run these boards at their max in parallel wiring. A couple of questions:

1. What are the advantages/disadvantages to running these drivers as opposed to the ones typically discussed for our growing needs? These are alot cheaper.
a. Do the HLG drivers offer some special features, protections that these cheaper ones don't? These seem to be "open", is
there a greater risk of shock? I plan on running it outside of the grow environment (tent).
b. Are these dimmable? If so, how are they dimmed?

Thanks again!

Did you measure the total voltage of the circuit with them all hooked up, rather than measuring a single board and extrapolating? This should be working without issue. I'm not sure why you're not getting full current. HLG even recommends using this driver for 4 of these boards in series. I was able to get full current in my test with 4 boards on this same driver.

Is your pot turned all the way up on that driver?

Hi LEDG,

I did measure single boards. I will repeat the test across all the boards. I did remove one of the boards, making it a 3 board set up, and measured the same way. The reading came it at 36.2V. The current on the 3 board setup was 1.9A, as opposed to 1.57, or closer to what is expected. This is what led me to believe the 4 board setup was too much for the driver. Also, the 3 board seems brighter than the 4 board. The driver is turned all the way up. I did choose it because of the HLG recommendation, this is what's so confusing. Could it be the 22 gauge wire?

My current readings. Turned all the way up.

3 board 4 board

DocBrownsGreenThumb wrote: ↑

Sat Apr 28, 2018 12:16 pm

...Could it be the 22 gauge wire?

I think you're onto something here.

Thicker wires will allow more current. LEDG suggests 18 gauge wire from Wago to board/strips, and 14 gauge from Wago to Wago. Also, the length of wire used can adversely affect power, especially with wire that is too thin.

Yeah, that could play a role. If the conductors are too small then there will be voltage drop which the driver will have to try to make up by increasing voltage output and if it's already at the limit due to the board voltage, it may not have the juice to compensate.

Thank you! I just ordered the 18 gauge. Will be here Monday. I'll run it and get new readings

DocBrownsGreenThumb wrote: ↑

Sun Apr 29, 2018 12:15 am

Thank you! I just ordered the 18 gauge. Will be here Monday. I'll run it and get new readings

If it makes the difference that might be worth writing an article on just to help anyone else seeing weird numbers. Don’t forget to update us!