PWM Dimming Controller For LED Lights or Ribbon, 12 Volt 8 Amp, 3301

Full Overview

Product Information Dimmer is a controller that it can adjust brightness infinitely,its control mode is knob-operated control, you could adjust light to the appropriate lighting brightness in accordance with your actual need. Technical parameters ? Working temperature: -20-60 ? ? Supply voltage: DC12V ?Output: 1 channel ? External dimension: L89 ? W59 ? H35 mm ? Packing size: L96 ? W64 ? H65 mm ? Net weight:8 5 g ? Gross weight: 10g ? Static power consumption: <1 W ? Output current: <8 A ? Max. output: 96 W

Technical Details

- Working temperature: -20-60 ?
- Supply voltage: DC12V
- Output: 1 channel
- External dimension: L89 ? W59 ? H35
- Packing size: L96 ? W64 ? H65 mm

We used this dimmer for a 16.4 foot LED ribbon, and it does dim that ribbon effectively. Two things to note:

1. It dims the LEDs in a non-linear fashion relative to the turning of the dial. Hence the first 45 degrees of rotation ( about 270 total) comprise the vast majority of observable change in the brightness of the LEDs. not a deal-breaker, but should have addressed in the potentiometer design. Could swap out the pot, but not worth it, really.

2. It doesn't fit a standard wall plate setup. It could be modified to do so, but with a bit of work.

Overall, it is adequate for the task.

Great product, works very well for my under-counter led lighting application. The dimmer box electronics can be relocated to a 2-gang cut-in box with switch on one side and dimmer control on other.

This item was purchased to slow down the speed of a small (amp) 12vdc gearmotor that was turning a suspended prop for a Christmas program. The unit is not advertised to control a motor, however the PWM circuit works fine for this application. Worked great.

I use this to power my LED strips. I purchased a power supply (item #B0034GUEY4) and I'm not sure if it's this dimmer or the power supply, but when I "dim" the voltage other than full 12 volts, my power supply hums/buzzes at a high pitch noise. It seems like it would be the PWM (pulse-width modulation) that's causing it. Since the dimmer has to switch the output voltage on and off at a high frequency to limit the output. I bet if I purchased a non-PWM dimmer then the buzzing would be gone. If I use my computer's power supply I can slightly hear the same noise inside that too.

Attaching a 12v computer fan to this dimmer (using above power supply or my computer's power supply) makes the fan produce some crazy noise when it's "dimming" the output voltage, even when I stop the blades from turning. Sounds like nails against a chalkboard. But when the dial is turned up all the way there's no noise from the fan and it's like normal. The power supply sounds normal this way, but it may be hard to hear with the noise from the fan. So using LEDs the noise is in the power supply (even slightly when I use my computer's power supply), but using a fan the noise is in the fan itself. Kind of strange. It may be related to the device powered, if it's current limited or voltage limited.

Also, the difference between the voltage in and the voltage out at full ON state can be about 0.19 volts. Meaning when I power my LED strip and put 17 volts in, the output at full ON measures 11.88 volts. Bypassing this dimmer when I wire the power directly to my LEDs I measure 14 volts. So this dimmer can limit the full output slightly. Not really a big deal. But, I think a non-PWM dimmer may reduce the output voltage even more making it less efficient. Have to read up on PWM to get the gritty details.

The green wire terminal connector is removable too, so that's kind of cool, just pulls out.

Also note, this dimmer IS linear. When I put 12 volts in and put a fan on the output, the voltage output measures about 6 volts when the dial is half way. I can measure 1 volt all the way up to 12 volts in a linear fashion. It's just that this dimmer requires a load to function. And using an LED strip as a load seems to cut the voltage output until the LEDs draw current at around 6 volts, the point at which they start to light up. The LEDs won't work with anything lower. It seems to me it's a limitation in the LEDs and the not the dimmer.

*UPDATE: I've removed the humming/buzzing by about 99.9% by putting a 16v 3300uf capacitor across the input voltage. This only works with the LEDs, not sure why the fans are unaffected. This seems like a design flaw in the PWM dimmers, if this issue affects you, but can be patched.

I have this connected to a full 5M light strip, and it works very well.

As a trial, I used a 12v battery for power.

When turned, the knob has a smooth feel and varies the lights without flickering.

It can be set from off to full brightness, and will dim to a very low light level without flickering.

I checked for RF interference with a Sony walkman, and there was no FM problem, but AM interference was heard within 2 ft of the dimmer, or a few inches from the strip. No problem at all 8 ft away.

The case is very sturdy, but a bit bulky.

I wish they made one with a long shaft to mount inside a cabinet with the knob outside the cabinet through a hole.

I took it apart, and it is possible to cut the wires and splice in a similar value potentiometer mounted through a cabinet wall.

Bottom line, I'm buying more of these.

*UPDATE* 1/26/12 -

After hooking up to a switching power supply with 2v ripple, there is a slight buzz mid range if loaded with 3 or more light strips, over 25 watts. Not very loud, just noticeable from 2 ft. in quiet room.

I purchased two more and found a difference in the circuit boards. The latest ones I received have smaller circuit boards and do not buzz at all. The newer model isn't as linear as the older one though, there is a jump in brightness near highest setting. Not very drastic, but there none the less.

I replaced the potentiometer (it's a 1k) with a longer shaft model, to fit through a 3/4" cabinet wall. The unit is inside the cabinet, and the knob outside. Looks much better.

Overall, I'm very pleased with both models.

I received my order of three units today and I hooked each one up and tested them, all worked. I noticed they were very quiet, not whining like a PWM controller does. I took off the cover and took a look inside. This does not look like the one in the picture; the PCBs are different and smaller.

I hooked the device up to my oscilloscope to take a look at the wave form. As I change the position of the potentiometer I saw the wave form change in AMPLITUDE not FREQUENCY. PWM changes frequency, that's why you will hear a whining sound and I didn't with these three units.

I'm not going to return them, they do what I want, control muffin fan speeds. But, SHAME on the seller for sending something else instead.

Showed up broken, with something rattling inside (same as another reviewers) Just stays on, can't even try it off. Bought a better one with an IR remote for cheaper off of Ebay.

Unfortunately, I can't say anything good about this product (well one good thing - see at end) --- and that's after buying two of them and having both fail. I am running well under 6 amps. I was hoping this would work for my LED strip lights because of the price, but I've wasted a lot of time returning these things. Going for better quality which will cost more this time. Lesson learned. The one good thing is the hassle free returns through Amazon (and their sellers). It's as good as mail order can be. Thanks for that.

Very rough feeling control and the brightness is jumpy when you turn it. Same thing as a scratchy volume control on a radio. But it was cheap and it works and I'm not adjusting it very often so I'm giving it 4 stars. I may change out the crummy potentiometer if it bugs me too much. Would I buy it again knowing what I know now? Sure I would.

On arrival the item is would not function as a direct or dimming device.
Installed an old fashion light switch as a temp measure.
Wasted $5.99, it's huge for its intended purpose anyway.