Sensors Lab questions

What are the four main sections of a capacitive proximity switch

-capacitive probe -oscillator -rectifier (detector circuit) -output circuit

What are the four main parts of an inductive proximity switch?

-coil -oscillator -detector circuit -output circuit

Name two parameters that affect the sensing distance of a capacitive proximity switch

-size of the probe -size of the target

Name two parameters that affect the sensing distance of an inductive proximity switch

-size of the probe -size of the target

What causes the maximum sensing distance of an inductive switch to be relatively short?

Eddy currents

What are the purposes of the filters in a polarized retroreflective sensor

For use in bicycles, cars, and signs

Explain why capacitive proximity switches must be spaced from surrounding surfaces and/or other sensors

It will affect the operation of the capacitive switch

What types of material do capacitive proximity switches detect?

Metallic and non-metallic objects

What type of material do inductive proximity switches detect?

Metallic objects

Explain why inductive proximity switches must be spaced from surrounding metallic surfaces and/or other sensors

Metallic objects affect the operation of inductive proximity sensors

For which applications are the retroreflective sensors designed

On a conveyer belt

Name the type of retroreflector that provides the highest signal return

Polarizing retroreflective surfaces

Explain why most capacitive proximity sensors are equipped with a sensitivity adjustment

Since they measure a dielectric gap, it is important to compensate for target and application conditions

Explain why retroreflective sensors are not well suited to detect small objects

The light will reflect around small objects

Name two reasons why polarized retroreflective sensors offer a shorter detection distance than standard retroreflective sensors

They use a visible LED light, and light loss are caused by polarizing filters