The Plan for today

I still don't have a temperature sensor, but I want to make sure that I give the ETS enough time to charge on Sunday and keep the space warm. The way that I want to do this is based on the room temp, if it is below 19C I want to make sure the ETS is on, during low power, and then off around 22C.

22C is about where I have the dial on the ETS set, which is something that I need to fix but it requires running another control wire.

What will the logic look like?

I'm starting with an expensive clock controller that takes no account of the temperature inside or out.

My first thought was something like this

This will work for the outside temperature, but "already warm" doesn't know the day of the week by itself. I will need to add timer to that one.

I'm thinking 4h is a good time to get started, and the way that ClickPLC works, when it's enabled the timer starts and stops when the enable is gone. The T1 only changes state when the timer gets to the setpoint.

So the "final" logic will look something like this.

Getting this into the PLC

The first thing that I need to do is get both inside and outside temperature into the PLC. Since I don't have these connected directly into the PLC, I need to get them from VTScada.

Modbus is the "easiest" way to do this, but this post has gotten long enough.

Stay tuned, that post is coming.