This project started because I had an Omega PID temperature controller that was laying around forever and I thought it would be nice to have an accurately controlled toaster oven. I mean an industrial PID controller must be able to regulate the temperature withing a few degrees which has to be better then the bi-metal system that these things use, right.
So I took it apart and cut the connections to the existing controls and used a tin snip to cut out a square hole for the 1/16th DIN controller. I added a sold state relay mounted on a heat sink the was to be controlled by the output of the controller. I used a T type thermocouple which I fed into the recirculating fan chamber. This is where I found out why the controller was just kicking around. It was broken! Specifically, it would not turn on the voltage output to control the SSR. (Solid State Relay).
I then, (actually many months later), bought an InkBird PID ITC-100VH controller. After installing this I noticed that I had a new issue where when it turned on the SSR the voltage would drop to the controller causing it to reset and turn off the controller. Once it finished coming up it would turn on the SSR, rinse and repeat.
After much thinking and poking I realised that the point I was taking one of the AC legs to power the controller was after it had already gone through the light. The light acts like a resistor which is what caused the voltage drop to the controller when the SSR turned on. The light only actually illuminates when there is a lot of current going through it. So it only lights when the heating elements are on. Moving the power line for the controller to before the light fixed the drop out issue.
I then wanted to change the controller from C to F, because AMERICA, when I realized that this controller only operates in C. Really why would anyone make a smart controller that wont do basic conversion math! Well I don’t want to have to do the conversions myself everytime I want to cook something so I ordered an InkBird PID ITC-106VH which is the exact same controller at the same price but this one does do both C and F operation.
When it arrived I removed the ITC-100VH and in opening the new one I realized they sent me an Industrial counter instead. I started the return/replacement process through Amazon and because I was frustrated and wanted pizza I put the ITC-100VH back into the oven and set it to 190.5C which is 375F. However, I never saw the heating elements glow red and after an hour it still did not reach its target temperature on the controller. Using a IR temperature measuring device I opened the door and took a reading of 357F. It would appear that the oven balanced out at around this temperature. (heaters vs temp loss) I don’t think it was reading the temperature accurately enough either possibly because the thermocouple was in the recirculation section which may not have been running. When the correct controller arrives I will also check if the fan is running and possibly change the thermocouple from a simple T type twisted wire to a K type probe mounted in the oven chamber directly.
