Using Photocell with a Dimmer or Potentiometer

First, you need to tell us what model # product you bought, and the power supply/controller #. Some LED driver/power supplies are not designed for dimming, rather they are replacements for existing lights. If you google LED with dimmer, you may find a better product.

If the LED fixtures are rated for use with a dimmer you need only to contact the manufacturer or search their website to find out what type of dimmer is compatible.

If the LED's are not dimmable then you will have to either replace the lamps with a lower "K" factor or you can change the wavelength (color) by manipulating the control circuit capacitance value which will soften the light.

Keep in mind that the color spectrum of LED's follow the pattern of higher "K" values yield whiter light and lower "K" values yield a more yellow light.

A 4000K LED appears much brighter and whiter than a 2700K LED which appears dimmer because the light wave color is more yellow.

LED lamps also come in variable Lumen ratings.

Example: Despite identical marketing advertisement printed on the box which states "direct replacement for a 60 Watt incandescent bulb " one lamp will actually output 8.5 Lumens and another 60 Watt replacement lamp will output 13 Lumens.

This means the 8.5 lamp will only output light at 65% of brilliance when compared to a 13 rated lamp.

Hope this helps you solve the issue.

If you're using a standard triac phase chopper or legacy dimmer, it is unlikely to work for your LEDs unless you couple it with something like the Texas instruments triac dimmable LED driver.

PWM type dimmers do not radically alter the colour temperatures with changes in brightness due to the fact that the current flow is either on or off rather than at a reduced level, and it is this forward current that determines the LEDs colour temp.

The switching frequency of the PWM dimmer (usually 200Hz or higher) then controls the average forward current through the LED and hence its brightness. A legacy dimmer does not alter the switching frequency but rather the on/off time relationship of a set, rather slow (50 -60 Hz), mains AC sine wave.

First step is to ascertain whether your LEDs are indeed dimmable, this information should appear on the lamp carton and often is also on the lamp base.

Next step is to obtain a C-L rated dimmer that is made specifically to dim LEDs. Lutron is probably the best of these and they normally have adjustable low end trimming capability as well.

The dimmer will need to be between the PE cell and the lamps.

Hope this helps.