Question 1

The six reasons sensors are used could be sumarized as: protect humans and machines from harm, for part identification and quality, for problem analysis, and to produce the fastest possible production.

Accepted Answer

The answer of The six reasons sensors are used could...

Question 2

Sensors are non -contact type devices, have electronics cirucits to generate the measurement, have numerous output circuit options, are always faster than switches , and require an external source of power.

Accepted Answer

Sensors can be contact or non-contact type devices, and while they often require an external source of power and can have numerous output options, they are not always faster than switches.

Question 3

Inductive type sensors use an electromagnetic field to sense the presence of a part.

Accepted Answer

Inductive type sensors operate by generating an electromagnetic field to detect metallic objects without requiring physical contact, making them ideal for sensing the presence of a part.

Question 4

Inductive sensors can only detect parts that have some magnetic material present.

Accepted Answer

Inductive sensors detect metallic objects without requiring them to be magnetic because they work on the principle of inducing eddy currents in the metal, which affects the sensor's oscillation and thus its output signal.

Question 5

A part entering the electric field of a capacitive proximity sensor causes the sensor output to change.

Accepted Answer

When a part enters the electric field of a capacitive proximity sensor, it changes the capacitance of the sensor circuit, which in turn causes the sensor output to change, indicating the presence of the part.

Question 6

Two of the five types of proximity sensors offered by vendors are wand and rectangular.

Accepted Answer

Common types of proximity sensors include inductive, capacitive, ultrasonic, and photoelectric, but not typically categorized as wand or rectangular. These terms might describe the physical form factor rather than the sensing technology.

Question 7

In general unshielded sensors have a larger sensing distance and a wider sensing area.

Accepted Answer

Unshielded sensors typically have a larger sensing distance and a wider sensing area because they are not encased in metal, allowing them to detect objects from a broader range and further away.

Question 8

The most popular type of proximity sensor style is the cylindrical threaded barrel type.

Accepted Answer

The cylindrical threaded barrel type is indeed the most popular style of proximity sensor due to its ease of installation and versatility in various applications.

Question 9

Capacitive proximity sensors generate eddy currents in the parts entering their electric field.

Accepted Answer

Capacitive proximity sensors detect changes in the capacitance between the sensor and the object being detected, not by generating eddy currents. Eddy currents are related to inductive proximity sensors.

Question 10

If you are required to select a sensor to detect a plastic part and you need the maximum distance possible, then you would choose an unshielded capacitive sensor.

Accepted Answer

Unshielded capacitive sensors generally have a longer sensing range compared to shielded ones, making them suitable for detecting objects like plastic parts from a greater distance.

Question 11

If you are required to select a sensor to detect an aluminum part and you need the a very narrow sensing field, then you would choose an unshielded inductive sensor.

Accepted Answer

Shielded (or embeddable) inductive sensors are designed to have a more focused and narrow sensing field compared to unshielded (non-embeddable) inductive sensors, making them more suitable for applications requiring precise detection in a confined area.

Question 12

A thin flat plate and large solid block of the same metal are sensed by an inductive proximity sensor, the large solid block would be sensed at a greater distance than the thin flat plate since it would have large eddy current values.

Accepted Answer

The answer of A thin flat plate and large solid...

Question 13

Mutual interference is only a problem when proximity sensors from different vendors are used too close together.

Accepted Answer

Mutual interference can occur between proximity sensors even if they are from the same vendor when they are installed too close together, as it is related to the sensors' operational frequencies and electromagnetic fields, not the brand or vendor.

Question 14

An inductive proximity sensor's output turns on when the internal oscilator starts oscillating but the capacitive proximity sensor operation is just the opposite.

Accepted Answer

An inductive proximity sensor's output turns on when a metal object enters its sensing field, causing a change in the oscillator's amplitude. Conversely, a capacitive proximity sensor detects changes in capacitance when a material (not limited to metal) comes close, but its operation is not the opposite in terms of oscillator behavior. Both types of sensors use changes in their electromagnetic or electrostatic fields to detect presence, but the materials they detect and the principles of detection differ, not necessarily the behavior of an internal oscillator in an opposite manner.

Question 15

Both inductive and capacitive proximity sensors can sense package contents through the packaging material.

Accepted Answer

Both inductive and capacitive proximity sensors can detect the presence of objects through non-metallic materials, such as plastic, glass, or cardboard.

Question 16

New setting distances for proximity sensors require experiment data for the actual sensing distance to make the calculations.

Accepted Answer

Proximity sensors often require experimental data to accurately set their sensing distances because factors such as the target material, size, and environmental conditions can affect the actual sensing distance, making theoretical values insufficient for precise settings.

Question 17

The two major components present in all photoelectric sensors are a source of light and a receiver to detect the light.

Accepted Answer

Photoelectric sensors work by emitting light from a light source, which is then detected by a receiver when the light beam is interrupted or reflected by an object, indicating the presence or absence of the object.

Question 18

Photoelectric sensors have five components that include a light source, light detector, logic circuit, lens, and output switching device.

Accepted Answer

Photoelectric sensors indeed consist of five main components: a light source (to emit light), a light detector (to receive the light), a logic circuit (to process the signal), a lens (to focus or spread the light), and an output switching device (to trigger a response based on the light received). These components work together to detect the presence, absence, or distance of an object.

Question 19

Photoelectric sensors have a much greater range than proximity type sensors.

Accepted Answer

Photoelectric sensors use light to detect objects, which allows them to have a much greater range than proximity sensors, which use magnetic fields or other short-range technologies.

Question 20

The photoelectric margin parameter is also called gain multiplier.

Accepted Answer

The photoelectric margin parameter is not called gain multiplier; it is typically referred to as the work function or photoelectric threshold, which is the minimum energy needed to eject an electron from a material. Gain multiplier refers to a different concept often associated with amplification in electronic devices.

Quiz 3: SCRS, Triacs, Other Thryristors, Discrete Automation Sensors and Devices