Question

Illustrate the use of (a) capacitive and (b) inductive sensors in a circuit where they are used to detect forward and return stroke limits for a double acting cylinder.

Answer 1

A. Capacitive sensors:

They are used in the probes to measure the position of the piston in a double acting cylinder. Capacitive proximity sensors sense "target" objects due to the target's ability to be electrically charged. When the piston reaches the extreme position the probe captures the distance of the piston during forward and return stroke.

B. Inductive sensor: Similar condition is used, with inductive sensor probes.Inductive proximity sensors are used for non-contact detection of metallic objects. Their operating principle is based on a coil and oscillator that creates an electromagnetic field in the close surroundings of the sensing surface.Inductive inductive proximity sensors can only detect metal targets. They do not detect non-metal targets such as plastic, wood.