Hi folks, I am having a couple of strange issues and I"m hoping you all might be able to help me figure out what's going on. I'm powering two qb288 quantum boards with a Mean Well HLG-240H-48AB driver and followed the video @LEDG posted to set up PWM dimming using an ESP32, PC817 optocoupler and 100 ohm resistor. I'm also using the same ESPHome config with PWM frequency at 1220 Hz.
So, the issues... First, the way the board is dimming is not only not linear, but seems to dim erratically and stops being responsive if I try testing the dimmer, up and down, a few times in a short period of time. For example, a light meter I have mounted in the corner f my tent reads 18,000lux when the LED is at 100% power, but jumps to 11-12k by 96%, but is still ~8k lux at 30%.
My second issue is that at 100% power (pwm) I am seeing both the apparent voltage and power (W) jump up above the driver's rating - ~330Va and W according to the Sonoff S31 (running Tasmota) the driver is plugged into. I was previously using a 100k dimmer pot to dim the boards and had the driver plugged into a power meter to keep an eye on the draw, so usually just kept it at 240W or below.
It's been a couple of years since I built this light, so I can't remember if I messed with the Io and Vo pots on the driver or not, but my understanding was that even running them at full on isn't really a problem.
Any ideas what is going on with either of these issues? Thanks for the help!
Over-voltage issue with Mean Well HLG-240H-48AB & PWM dimming
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Rocket Soul
- LED Lover
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- Posts: 111
- Joined: Sun Apr 22, 2018 10:11 am
Im going to throw out a guess: problems may be related to being AB dimming driver. Iirc theres like some over ride from the onboard dimming over the external dimming, there might be a conflict there but as stated, throwing guesses.
The driver youre using does it have full A -controls onboard, as in both voltage and current dimming plus then the of board cables? I never had one myself and i know theres been some unclear indications from meanwell on some models. Like datasheet says yes but they dont show up in some pictures etc.
The driver youre using does it have full A -controls onboard, as in both voltage and current dimming plus then the of board cables? I never had one myself and i know theres been some unclear indications from meanwell on some models. Like datasheet says yes but they dont show up in some pictures etc.