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I am trying to replace a (suspected) constant current LED driver in a plant lamp as it has a terrible plastics smell. I am searching for a more high quality driver. I do not know then forward voltage of the LEDs, and at the moment I do not have a multimeter at hand (I will next week).

Driver to be replaced: current LED driver

So far I have understood, that I will have to pick a constant current LED driver, which supplies 650mA and which voltage range convers at minimum the entire range of the current driver.

I have found the Mean Well HLG-60H-C700A, which supplies 420 ~ 700mA (adjustable via inbuilt potentiometer) and 50 ~ 100V, which should cover the needed voltage range.

The current driver is dimmable, but I do not really need that functionality. I am fine with setting the driver to some output current, and then leave it there.

I have the following questions:

  1. Will the Mean Well driver be able to replace the current driver (as its max voltage is significantly higher than the current drivers)
  2. Can I adjust the output current to, say, 500mA and by that drive the LEDs at a lower brightness? Will this cause the driver to output significant heat (I could not find out if it is linear).
  3. Assuming I wanted to add dimming functionality (e.g. through an ESP8266 and PWM, using the mean well B model). How would I limit the driver to 650mA? Is this what the AB model achieves?
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    \$\begingroup\$ 1. yes. 2. yes, using the pot and no, it's not linear. 3. set the pot to determine max, then dim down from there. \$\endgroup\$ – dandavis Oct 4 '20 at 8:09
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Will the Mean Well driver be able to replace the current driver

Yes.

Note this meanwell driver has a Protection Earth wire which must be connected. Your original wire does not.

Can I adjust the output current to, say, 500mA and by that drive the LEDs at a lower brightness?

Yes

Will this cause the driver to output significant heat (I could not find out if it is linear).

No, dimming controls the switching converter inside. Efficiency vs load is mentioned in the datasheet. While efficiency decreases slightly at light load, it's still pretty good. At max output power, having low % losses is important. At low output power it matters less.

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Assuming I wanted to add dimming functionality (e.g. through an ESP8266 and PWM, using the mean well B model). How would I limit the driver to 650mA? Is this what the AB model achieves?

Yes it'll work.

If you want the ESP8266 to be able to turn off the Meanwell supply, then ESP8266 needs its own power supply, like a USB cellphone "charger". Besides powering it from 60V would be inconvenient.

Note datasheet says DO NOT connect "DIM- to -V"

Check if the Meanwell can turn off the LED completely. I don't think it can. So if you want this you'll probably need a relay driven from ESP8266 to switch the mains.

Dimming needs a 10V PWM though, so an ESP8266 powered from 3V3 won't achieve this.

However the Meanwell has a built-in 100μA current source pulling the DIM input up to 10V. All that's needed is a transistor driven by PWM to short the DIM input pins together. You can also use an optocoupler. When the transistor/opto is on, it shorts the DIM input. When it's off, the internal 100µA pulls it up to 10V. So all you have to do is PWM the transistor's base (or the opto LED) and here you go.

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    \$\begingroup\$ perfect, thanks a lot! I am switching the light using a zigbee plug, therefore turning off completely is no issue should I decide to dim them. Thanks for the tip with the optocoupler, thats what I will do. \$\endgroup\$ – acknexster Oct 4 '20 at 10:39
  • \$\begingroup\$ For dimming, you only need a POT or a simple resistor to control the output current. To turn off the supply, I think you just need to open (turn off) the connection between DIM+ and DIM-. \$\endgroup\$ – Fredled Oct 4 '20 at 11:03
  • \$\begingroup\$ Open between DIM pins sets it to 100%. \$\endgroup\$ – bobflux Oct 4 '20 at 11:14
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Assuming I wanted to add dimming functionality (e.g. through an ESP8266 and PWM, using the mean well B model). How would I limit the driver to 650mA? Is this what the AB model achieves?

The AB model includes dimmer pins for a microcontroller and a dimmer knob on the power supply. Unless you need to remotely control the brightness, you can simply turn the knob to set the brightness.

Also, these power supplies are usually turned off by using a relay on the mains side. This is by convention for agriculture lighting.

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  • \$\begingroup\$ How do the internal knob and the external dimmer pins on the AB model work together? Is it the minimum of both, or can the external pins override the internal knob? My plan would be to set the maximum current via the internal knob and then not have to worry about setting a to high current via the external pins (via PWM in my case). \$\endgroup\$ – acknexster Oct 4 '20 at 21:00

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