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Adding potentiometer on Chinese LEDs?
- Thread starter kschweer
- Start date
This isn’t coming from me, but from Der Wille Zur Macht over on RC who is an LED guru…
You (typically) CAN NOT dim or control a typical LED rig by adding a resistor or potentiometer (sliding or otherwise) to the DC output, i.e. in series with the LED string. 99% of commercially produced HP LED rigs use an active circuit to drive the LEDs, which means it self-adjusts to maintain a preset current level. If you tried to "reduce" the power in the LED string by burning some of it off in a potentiometer, the driver would simply adjust the voltage level in the string upwards until the current in the LEDs returned to its target value - it would completely thwart your attempt to dim the LEDs. This may be confusing for some people but it's important to remember that LEDdrivers are inherently constant-current devices, as opposed to the vast majority of other drivers/power supplies typically toyed with in hobby electronics which are inherently voltage-regulated, not current-regulated.
What it boils down to is simply this: The only reliable and surefire way to dim a string of LEDs driven by an active constant current driver is to use the driver's built-in dimming functionality. If the driver has no such functionality, you're SOL and the only realistic way to proceed is to replace the driver with one that is controllable or simply replace the entire rig with one that is meant to be controllable.
You (typically) CAN NOT dim or control a typical LED rig by adding a resistor or potentiometer (sliding or otherwise) to the DC output, i.e. in series with the LED string. 99% of commercially produced HP LED rigs use an active circuit to drive the LEDs, which means it self-adjusts to maintain a preset current level. If you tried to "reduce" the power in the LED string by burning some of it off in a potentiometer, the driver would simply adjust the voltage level in the string upwards until the current in the LEDs returned to its target value - it would completely thwart your attempt to dim the LEDs. This may be confusing for some people but it's important to remember that LEDdrivers are inherently constant-current devices, as opposed to the vast majority of other drivers/power supplies typically toyed with in hobby electronics which are inherently voltage-regulated, not current-regulated.
What it boils down to is simply this: The only reliable and surefire way to dim a string of LEDs driven by an active constant current driver is to use the driver's built-in dimming functionality. If the driver has no such functionality, you're SOL and the only realistic way to proceed is to replace the driver with one that is controllable or simply replace the entire rig with one that is meant to be controllable.
Thanks Paul. Kinda figured it wouldn't work out. Not sure if you saw my new build thread but I'm looking into doing a glass holes overflow. Would you maybe be able to help me out if I come up your way. I know you've used them before and I have no real experience with installing them
Kevin, not a problem. Let me know when you'd like to take the trip. Also, have you watched any of the Glass-Holes videos?
Slow and steady is the key! I've done 3 tanks now with glass-holes kits. Two are my own tanks and one was for another club member.