Control Yes/No

The yes/no controllers, also called "on/off" or "on/nothing" controllers, are the most basic control systems. These send an activation signal ("yes", "on" or "1") when the input signal is less than a reference level (predefined), and deactivate the output signal ("no", "off" or "0") when the input signal is greater than the reference signal.

The «yes/no» controllers are used in air conditioning thermostats. These activate cold air ("yes") when the temperature is higher than the reference (the user's preference) and deactivate it ("no") when the temperature is already lower (or equal) than the reference.