I'm working on a project with a Micrologix 1400 with a temperature control PID block. The system has both heating and cooling, but the tricky part is that the cooling is not always enabled. What we have done in the past is rescale the PID so that when cooling is disabled 0-100% is heating and when cooling is disabled 0-50% is cooling and 50%-100% is heating. I'm not sure this is the best way to approach it and was thinking about having two PID blocks. One for heating and one for cooling. Anyone have any experience with this type of setup?