A Digital Potentiometer solution required

So I am putting together a controller to control the electric radiator in my office, code wise it is fine, I can move the setpoint against time, manually, web page, or Alexa. However I've got an electronic problem, I bought a Chinese electronic controller to control it (double the rating - just in case!), and output is currently controlled with a 500Ω 2W potentiometer. Looking at the track size it seems to need the power.

I can find various digital potentiometers at higher resistance, both none at either 500Ω or with anything like the power rating to replace the analogue part. Any suggestions? Ideally I'd like to control it with an UNO analogue output, but right now open to ideas!

You can use a stepper motor to rotate it as a last resort. Beyond that, schematics, model numbers etc would help a lot.

As I see it I need a circuit to emulate the 500Ω 2W potentiometer that responds to a 0-5V input, I've not got a part number, its an ebay 'special'. Alternatively is what I need is a suggestion for a 230Vac 2KW power controller for the radiator that can be controlled or modified to work with the Arduino output. I did see a heater controller with a digital display and up/down switches, perhaps that is more applicable? Code I can work through, electronics I have little knowledge of.

A pictures of the PCB.

So I bought another chinese special, this one with a digital display that controls the output. So I put a 'scope on the output and attached are the screenshots of various output (1, 49, 50, 99%). Peaks are 500mV, and cycle is 50 Hz. So it looks like the half wave rectification is reference and as value increases the trigger moves from end of each cycle toward start, and at 50% moves to a much longer high (550µs instead of 100µs). Any chance of duplicating this with an UNO?

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There is no chance, unless you are able to sync the Arduino to the frequency of your mains power. Why no use a plain old SSR to control the heat?

Paul

Um, what is an SSR? I can do a number of things but electronic design isn’t one of them, and searching SSR I got a lot of stuff not related!

So I’m not sure how I’d use and interface to keep it safe. Can you offer a pointer?

Edit: Found solid state relay, but my original thought was to use a thyristor to get zero crossover switching and avoid any RFI issues. Hence the original controllers offering a level of proportional output.

AmphenolSensors:
Um, what is an SSR? I can do a number of things but electronic design isn’t one of them, and searching SSR I got a lot of stuff not related!

So I’m not sure how I’d use and interface to keep it safe. Can you offer a pointer?

Edit: Found solid state relay, but my original thought was to use a thyristor to get zero crossover switching and avoid any RFI issues. Hence the original controllers offering a level of proportional output.

Yes, SSR is solid state relay. You are dealing with a heating system. Time lag is likely in minutes, a simple on and off will work just fine and that is what a SSR will do for you. Control with a digital output pin from you Arduino,
Paul

The SSR uses a thyristor to turn the AC on and off. The internal logic detects zero crossing. All done for you!