Which of the following statements describes the operation of the circuit shown in the illustration? Illustration MO-0114

Correct Answer: Option D — The output from "2" is equal to the input to "1" except when the input of "1" is between the setpoints of '17A' and '17B', when it will remain at the value of '17A'.

Pneumatic signal selector relays pass input signals directly unless thresholds 17A and 17B are reached, holding output constant at setpoint 17A during the intermediate transition band.