A programmer or switching apparatus produces an on and off valued control signal for turning and associated controlled component on an off at preselected points in the variation range of a reference variable. The apparatus includes a reference trance looser for converting your reference variable in to a reference signal representing the variable. A pair of set points services provide appear upset point signals which are compared with the reference signal to defined operating points at which the control signal switches between it’s on and off values.
The apparatus has the versatility of allowing by nearly setting the set point to prices in without making any circuit changes depressed transition up the control signal to be either from on to off and off to on as a reference variable increases from its minimum to its maximum value. Basic units are part basic units may be combined to provide a number of control channels controlling the operation of a number of controlled components in response to the same reference variable.
The reference bearable the angular displacement of a rotor bowl shaft which may rotate continuously in one direction through repeated revolutions on which oscillate back and forth between given and points it may also be the linear displacement of a linearly movable element or it may be some other continuously variable quantity such as elapsed time temperature pressure liquid level like center.