To set-up a PID control with Delta PLC’s is not a big deal.
You only need the set Point, the present value, configure it as you need (or use auto-tuning to avoid complications), and put everything on PID instruction (API 88).

Depending If your device to control the temperature needs pulse output or analog, you can use the value directly for analog, or the instruction GPWM (API 144) to control the heat with Pulse Modulation signal.

But what happen If your system have double output? (heating and cooling)

Of course you can always use our DTB temperature controllers to solve that problem easy and fast, but If you need to do it with one of our PLC’s.
Take a look to the following program.
PID_heating and colling.dvp