# Potentiometer circuit to DC-Dimmer circuit: 3 wire to 4 wire connection?

#### NAND4011

Joined Mar 4, 2021
3
Looking for a plausible solution to the following problem:

Background:
1. Currently - simple potentiometer (linear, 100k Ohm) control that controls an AC motor

2. Motor has a dedicated DC control circuit embedded with the following possible control connection points a). "Low Voltage +10V; b). "Low Voltage 0-10V", c). "Low Voltage - GND"

3. DC Dimmer switch has the following connection points : a). "Input V+", b). "Input V-", c). "Output V+", d). "Output V-"

3. My raw rough notebook page with my best attempt to decode a rough circuit of the components: potentiometer, motor, DC dimmer based on the voltage measurements I took from the available connection points of each component. The potentiometer was measured at its connection while actively connected to the motor. DC dimmer switch was measured on the bench with a 10V DC voltage supply.

Problem:
1. Motor has 3 wire connections currently connected to the potentiometer. Is it plausible for this motor to even be connected to a 4 wire DC dimmer?

2. If it maybe plausible, does there exist a solution that uses just the 3 wires coming from the motor and connected to the DC Dimmer without any modification to the motor?

Notes:
- Im new to this forum, but have been a follower for a long time.
- I have no training in electrical engineering. My training is in Electrochemistry and Biochemistry.
- I apologize in advance if I have posted a problem that is elementary to the group and/or obvious answer based on basic theory. Unfortunately, it is escaping me after all my attempts to apply the basic theory as I understand it.

#### LowQCab

Joined Nov 6, 2012
3,956
An LED Dimmer uses special circuitry specifically designed for an LED -Load.
You can not use the LED Dimmer to control this Motor.
You already have a good working solution,
what's wrong with what you have now ????

Why are you trying to create an "unusual-solution" to a problem that doesn't exist ??
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#### NAND4011

Joined Mar 4, 2021
3
Thanks @LowQCab for clearing up for me. I appreciate it the respectful reply to an unusual question.
what's wrong with what you have now ????
--> Purely an aesthetics issue;

Why are you trying to create an "unusual-solution" to a problem that doesn't exist ??
--> You are correct, the existing solution solves the problem from a technical view; albeit, I was trying to solve for a design/aesthetics. Attempting to replace the POT enclosure with a: 'professional' looking enclosure designed to be wall-mounted into an existing electrical device box. My search found no options for a POT control, but a few DC dimmer controls, such as the one above. It seemed promising and I gave it an attempt.....

#### LowQCab

Joined Nov 6, 2012
3,956
If it is possible to take apart the LED-Dimmer without destroying it ...........
You can Probably just "Gut" the Electronics,
and use the Pot that's already there in the LED-Dimmer.

But, depending upon the
of the Motor-Speed-Controller,
you may have to "trans-plant" the old Pot into the New Housing.

There may be an easier solution .................
Common Wall Plates are available in an absolutely crazy number of configurations,
and you can get them in un-breakable Nylon, and, Polished, or "Brushed-Finish" Stainless-Steel.
All of these various Wall-Plates are available in all the "Standard-Configurations".
The "Style" that you want has just a single ~3/8" Hole in the Center, for a single wire or cable.
This is the perfect sized hole to accept the Threaded-Shaft of a standard "Full-Sized" Pot.
Which is probably what you already have,
( except that I wonder why it's in such a huge plastic-box right now ).

Then it just comes down to selecting from about a "Billion" different Knob choices,
to "Match your taste in Decor".

If you want a "Classically" styled Knob,
that is easy to determine the position of from across the room, with just a glance,
get a style of knob called a "Chicken-Head" Knob.
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#### NAND4011

Joined Mar 4, 2021
3
Thanks @LowQCab
I've found a blank cover plate. Will drill a hole for the pot and find a better knob as in your pic. Will get a decal made up from a print shop.

#### Alec_t

Joined Sep 17, 2013
14,234
use the Pot that's already there in the LED-Dimmer.
Is there one? The dimmer is a touch-panel type.

#### Ya’akov

Joined Jan 27, 2019
8,975
Modern LED and fluorescent dimmers (for compatible lighting) produce a 0-10V DC signal to operate a dimmer built into the fixture.

I recently installed such a dimmer for LED panels in a drop ceiling. I noticed it did not produce any output without a load, so testing it disconnected might fail.

But, if the controller properly loads it, and needs a 0-10VDC control signal, it seems it would work.

#### djsfantasi

Joined Apr 11, 2010
9,154
Thanks @LowQCab
I've found a blank cover plate. Will drill a hole for the pot and find a better knob as in your pic. Will get a decal made up from a print shop.
Drilling a nylon cover plate is difficult. If you use a metal bit, the nylon shatters around the drill hole. Ask me how I know...

You can use a variety of bits to successfully drill a hole. A 1/16” bit to drill a pilot hole. A properly sized wood but with edge cutters to drill from both sides. And a properly sized metal bit to remove the nylon in the center of the hole.

The wood bit edge cutters cut the outside circle preventing chip out. But the wood bit isn’t good for cutting the mass of material in the hole center. That’s why you use a metal bit. Use a fast speed on the drill, but insert the bit in small increments. A drill press is recommended. Ensure that the cover plate is strongly secured. The drill but can catch and make the plate fly across the room.

#### ttocsmij

Joined May 30, 2018
9
I've had success drilling plastic and nylon cover plates using a drill press at low speed (400 RPM or so) and brad point drills (mine are Black & Decker). Make sure the surface you are drilling is solidly supported so no distortion of the drilled surface occurs (i.e., I drill them front / face surface down). The lower speed ensures that any thermally-sensitive plastic doesn't melt and clog the process. A 1/32 inch or 1/16 inch pilot hole ensures the brad point goes in the right place reliably. It takes a little practice so get some plates to practice on first.