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LED Dimmer Knob - Dim up to 6 Amps of 12V LEDs - Easily mount to a panel - Customer Questions

Frequently Asked Questions by Oznium Customers

Can this be installed under the hood of a pickup near the fuse box to dim an LED grill logo light. Instead of running wires into the cab. Just wondering if under the hood would be out of the weather enough to protect it. Does it run very hot when dimming an led light.
It does not run hot. This one isn't waterproof and shouldn't be installed under your hood.

We have a waterproof LED dimmer that will work under your hood.
can this dimmer switch be used with the your fade in/ fade out switch
Not really, when using an external dimmer knob the fade is choppy and the bulb does not give a steady light.
Will a DC power supply that puts out more than 6 amps damage the switch?
No, the amperage is the load of leds the power supply can handle.
The underside of the circuit panel of the dimmer is coated with some black protective film. How can I remove the black protective film so I can desolder the knob from the circuit panel and mount it remotely? - by Patrick (Mississauga, Canada)
You can use a heat gun and then carefully scrape the black stuff off to expose the solder points of the knob.
What is the maximum panel thickness allowed for mounting?
The knob is a little over 1/2=.38 inch exactly. If you need more dimensions you can find then here: https://www.oznium.com/switches/led-dimmer-knob#tech
is this dimmer a pwm - by Ronald (United States)
Yes, here is some tech info: https://www.oznium.com/switches/led-dimmer-knob#tech
Hi, I purchased this dimmer and connected from fuse to dimmer, then from dimmer to led drl. I tried 2 different dimmers, but on both power came through constantly. No on/off and no dimming. Are they defective or did I do something wrong? - by NICK (Kingwood, TX)
It sounds like you're wiring something wrong.

Have you looked at the "Technical Info" tab on the product page?

As with pretty much all dimmer switches, the ground side is switched rather than the positive side. So you must hookup the output ground wire to your LEDs.

Below is a quick video showing how to hook up your wires. If you find that your LED lights are not dimming, nor turning off, it doesn't mean the dimmer is defective. It just means you've wired something incorrectly. Please go back, double, and triple check that you're wiring it according to the above diagram / below video.

Am going to use this dimmer with the surface mount 5050 led. Do I have to remove the resistor from the led? - by William (China Grove, NC)
You should keep the resistor as-is.
Referring to the first question, how would you wire the dimmer to a switch to eliminate constant draw? Also, the ground IN can come from a bolt in the car correct? Doesn't have to be from the battery. - by Justin (Palm Bay, FL)
You could simply put a switch on either the 12v or 12v- IN wires. Like this:
Wire Switch to LED Dimmer

Yes, the ground IN can come directly from a bolt on your car. The ground OUT can't go directly to a bolt. It must go direct to the 12v- of your LEDs.
If I use the LED Dimmer Knob on a boat, any continuous current drain. no matter how small, will eventually run the battery down. Does the LED Dimmer draw any current from the 12 volt supply while clicked to the OFF position? If so, how much?
The LED dimmer knob still draws 3mA when clicked to the OFF position.

To avoid this current drain, a physical switch could be added in the circuit to completely remove power to the dimmer.
If you are installing an "Add a Circuit" to the car's fuse box to provide the positive voltage to the LED's, can you have the negative go to a ground on the car for this to work properly? The LED's will still go to the positive and negative of the dimmer, but the negative in from the power source would be a ground wire to ground in the car (ex. ground bolt)?
Yes
I purchased some blue and green superflux LED's a few days ago. I'm interested in purchasing this dimmer. I know that the LED's negative should go to ground in the car. Can I instead have the ground go to negative on the dimmer for this to work properly? A similar question was asked earlier but not if we have the ground side of the Superflux LED's go to negative return on the dimmer for this to work properly.
Yes, that is exactly the way you must hook it up.
This dimmer (and pretty much any other LED controller) switches the ground side and not the positive side.
So you certainly shouldn't (and can't) hook up the LED ground to the physical metal of the car. You must hook it up to the ground output from the dimmer.
Just follow the wiring diagram on the "Technical Info" tab, and it should work fine...
Please, I have a avionics panels with back lighting integrated by 3,2V smd led . Can I use this dommer board with 5V instead 12V?.
Wait from you, thank you in advance.
Best regards, Pacifico Foresi - by Pacifico (Italy)
As shown on the "Technical Info" tab:
Supply (Input) Voltage: 8 to 20VDC working voltage, up to 30VDC momentary
So its not designed to work with 5V, but it may still work for you with mixed results.
Say I had two single LED lights, One on the left and one on the right (just to distinguish the two). The left LED's + input is from a switch, while the right LED's + input is from a different switch. The switches are independent from each other. If I hook up the - of both LED's into the dimmer, will this work? Can LED's have independent electrical +'s and share a dimmer knob on the - end?
Thank you! - by Hunter (United States)
Yes, I'm pretty sure this will work. Go for it!
I wanted to use this dimmer to mount on a bar back, but I'm mounting it thru 3/4" plywood. Anyway to extend the shaft so it will work?
Yes, you're certainly welcome to extend the shaft.
Can I use this dimmer without removing my boats panel switch? Do I tap input and output from my panel switch to this unit? All + and - are on that circuit so I know it will work. I just dont want to remove my dash panel switch. Thanks. Any advice would be great. - by Nikos (los angeles)
-There is a IN port for the hot and ground wire, wires from your and - would plug into that. I don't see why you would need to remove your dash panel switch but I don't know how it is setup.
Can this dimmer, "LED Dimmer Knob - Dim up to 6 Amps of 12V LEDs" be left in one position and switched on and off with the head-light switch ?

Thanks - by GrevB (Gloucester, MA)
Yes, of course!
How many LEDs can be hooked up to this dimmer ?

Do you have any other dimmers, something small and screwdriver set, sort set and leave it ? - by Greville
It depends how much current your LEDs use.
Your limit is the amount of current you can pass through the dimmer.
As you can see from the Technical Info tab, the max current is 6 amps.
So once you figure out how much current each of your LEDs draws, you will then be able to figured out how many LEDs you can hook up to this dimmer.

We have a handful of dimmers. All of them can be set and left. Don't know what you mean by "sort set".
I have your Rigid 5mm LED Dome Light
and also the Super Strong Flexible LED Strips for inside the bed of my truck
Loads of light sometimes I would like it NOT so bright,Can I hook this dimmer directly in line to the LED wire? If not do u have one I can
Yes
Will this product work where all LED's are on a common ground? i.e. Both ground leads are grounded to the car, input is the +12-14VDC and the LED's are connected to the variable +12VDC ouput. Please advise. - by Cecil (Washington State)
No.
We would like to mount this in a typical 1-Gang Electrical wall Box but are concerned about how much heat it gives off. How hot does the heat sink on this dimmer get? Thanks. - by AngelArs
We have not yet tested how much heat it gives off.
What frequency does it operate at? - by Will (Gainesville, FL)
455Hz