Argyll Gargoyle
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- Joined
- Jun 7, 2020
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I bought a stir plate with a heater, since I build my starters in the basement. Sometimes it gets too cold, and because I step up from slants, I don’t want the whole process to take forever.
Well, it turns out the existing temp adjustment is pretty worthless. It goes from 0 to 11 with hardly any adjustment in between — and inconsistent to boot. I cooked my last starter, and that tears it!
So I ripped out the guts and implemented a PID controller using a small SSR, a digital temp sensor, and an arduino board.
The temp sensor is the small black cord on the left-hand edge of the hot plate. It goes into a hole drilled into the aluminum plate. Control wires for the SSR and motor are run out of the box for testing, but will be put inside along with the arduino. The unconnected pcb near the arduino is the old control board.
Here it is settling a step in temp from 30C to 35C. Time samples are about 2-3 per second
I can provide additional details if folks are interested. I haven’t seen many builds like this (or any?)
The stir plate was 50-60 bucks, SSR board $10 or so
Well, it turns out the existing temp adjustment is pretty worthless. It goes from 0 to 11 with hardly any adjustment in between — and inconsistent to boot. I cooked my last starter, and that tears it!
So I ripped out the guts and implemented a PID controller using a small SSR, a digital temp sensor, and an arduino board.
The temp sensor is the small black cord on the left-hand edge of the hot plate. It goes into a hole drilled into the aluminum plate. Control wires for the SSR and motor are run out of the box for testing, but will be put inside along with the arduino. The unconnected pcb near the arduino is the old control board.
Here it is settling a step in temp from 30C to 35C. Time samples are about 2-3 per second
I can provide additional details if folks are interested. I haven’t seen many builds like this (or any?)
The stir plate was 50-60 bucks, SSR board $10 or so