Question

A differential device used to measure the actual controlled quantity and to compare it continuously with the desired value is called

(a) regulator

(b) kinetic control

(c) feed back

(d) error detector

This question was addressed to me in a job interview.

Query is from Automatic Control topic in chapter Automatic Control of Machine Dynamics

Answer 1

Right answer is (d) error detector

The explanation: The device used to keep the variables at a constant desired value is called as regulator. The instrument measuring the output of the machine for comparison with the input to the machine is known as feedback. The automatic control of the displacement or velocity or acceleration of a member of a machine is called as kinetic control. A differential device used to measure the actual controlled quantity and to compare it continuously with the desired value is called error detector.