On the engine of fashion. 2106 the microswitch of 421.3709 type influencing the electromagnetic valve besides the control unit is used.
The microswitch is executed by normally closed.
At completely released pedal of management of a butterfly valve the pusher of the microswitch is drowned and its contacts are opened.
By sufficient pressing the specified pedal the pusher of the microswitch is released and its contacts become isolated. At the same time current passes through a winding of the electromagnetic valve irrespective of the control unit.