Manual operation makes life easier
In building automation as well as in process control, it is very practical to switch a relay contact or, with an analogue value transmitter or a manipulated variable transmitter, an analogue signal of 0 - 10 V or 0 - 20 mA on and off without a controller during commissioning or servicing. This means switching a valve, pump, heating or ventilation in manual mode or operating a valve, mixing flap, temperature values, etc. with an analogue signal.
If the controller should fail, emergency operation can be established with the manual operation and long downtimes can be avoided.
In order to ensure that everything is switched to automatic when leaving the plant, the Auto - OFF - MAN switches are equipped with an additional potential-free contact. This transmits the operating state of the coupling components to the controller.