Simplicity on the Worksite Solutions Guide for FAQs: E5CC/E5EC Using PID Control The procedure to use PID control is given step by step in this section. The default setting is for reverse operation. For heating control, select reverse operation. For cooling control, select direct operation. Manipulated variable Reverse Operation (Default) Manipulated variable Direct Operation 100% 100% 0% Temperature 0% Temperature Set point Set point The manipulated variable increases if the temperature is lower than the set point. The manipulated variable decreases if the temperature is higher than the set point. The manipulated variable decreases if the temperature is lower than the set point.
The manipulated variable increases if the temperature is higher than the set point. Using PID Control You can automatically or manually set the PID constants that are used for PID control. Adjusting the PID Constants The suitable values of the PID constants that are used for temperature control depend on the characteristics of the controlled object. There are three ways that you can use to set the PID constants. These are described below. ⇒ Use autotuning (AT). If you ca n allow the temperature to vary while tuning the PID constants and you need to calculate the optimum PID constants: ⇒ Set the PID constants manually. If you know the PID constants in advance:
If you cannot allow the temperature to vary and you need to automatically estimate the PID constants when the set point is changed: With self-tuning, calculation of the PID constants is affected by changes in the temperature, such as when a heater is turned ON and OFF. The PID c onstants will be automatically calculated and set. If there is an external source that causes temperature changes (such as a heater turning OFF), u se autotuning or set the PID constants manually. ⇒ Use self-tuning (ST). Simplicity on the Worksite Solutions Guide for FAQs: E5CC/E5EC 3-1 Using PID Control Step 1 Determining the Control Method 1 Select direct or reverse operation.
Heatin g Cooling 2 Adjust the PID constants.