Deck 19: Proximity Detectors

Question 1

Proximity detectors used to sense all types of metals will sense nonferrous metals better than ferrous metals.

Answer 1

False

Question 2

Capacitive proximity detectors depend on metal to operate.

Answer 2

False

Question 3

If proximity detectors are used in areas that contain metal shavings or dust, an effort should be made to do what?

Answer 3

An effort should be made to place the sensor in a position that will prevent the shavings or dust from collecting around it. In some installations it may be necessary to periodically clean the metal shavings, or dust away from the center.

Question 4

Figure 19-02

In the accompanying figure, the presence of metal is causing a(n) ____________________ of voltage across the register.

Question 5

How do ultrasonic detectors operate and what can they determine?

Question 6

Figure 19-09

The accompanying figure shows ______________________________ detectors used as position sensors.

Question 7

Sensors should be mounted as close to other metals as possible.

Question 8

Some proximity detectors employ sound waves and can be used to detect the distance to an object or to determine the position of a object.

Question 9

Why are many capacitive proximity detectors being used to replace mechanical limit switches?

Question 10

Proximity detectors are used to sense the presence of an object without physically touching it.

Question 11

A(n) ____________________ is a device used to generate alternating current at a desired frequency.

Question 12

One disadvantage of capacitive proximity detectors is that they have a very limited ____________________.

Question 13

Figure 19-05

In the circuit shown in the accompanying figure, what happens when a nonferrous metal, such as aluminum, copper, or brass, is placed near the sensor coil?

Question 14

Figure 19-02

In the accompanying diagram, when the current flow through the resistor is decreased, what happens to the voltage?

Question 15

Figure 19-03

The accompanying figure shows a detector that uses a tank circuit tuned to the frequency of the oscillator. This type of sensor is a(n) ____________________.