Module 2 : Industrial Control Devices

Question 1

SCR (Silicon Controlled Rectifier)

Answer 1

Three-terminal PNPN device that acts as a gated diode. The gate terminal switches the device in allowing current to flow from anode to cathode.

Question 2

Commutation

Answer 2

Interrupting current, such as through the various windings of a DC motor armature.

Question 3

Ladder Logic

Answer 3

An industry standard which uses successive horizontal lines with symbols to represent the logic operation of a control system.

Question 4

Relay Logic

Answer 4

A method of controlling industrial electric circuits by using relays and contacts.

Question 5

Actuator

Answer 5

Lever, arm, or wand.

Question 6

Positioner

Answer 6

A servomechanism that moves to persis location

Question 7

Hydraulic actuators

Question 8

Two types of interfaces used in robotic circuits

Answer 8

electrical and hydraulic

Question 9

Single Pole switch

Answer 9

single pole switch only allows the current one circuit to pass through

Question 10

(NO)

Answer 10

Normally Open

Question 11

(NC)

Answer 11

Normally closed

Question 12

Pole

Answer 12

Movable contact on the switch. A completely isolated circuit that is allowed to pass through the switch

Question 13

Thow

Answer 13

The number of positions in which the switch can be set.

Question 14

What term describes the number of completely isolated circuits that pass through a switch at a given time?

Answer 14

POLE

Question 15

What term describes the total number of individual circuits that each pole is capable of controlling?

Answer 15

Throw

Question 16

How are switched rated?

Answer 16

Switches are generally rated by their current-handling capability and the type of load they can control.

Question 17

Which proximity switches are suitable for high-speed counting applications?

Answer 17

RF inductive proximity switches

Question 18

Capacitive proximity switches can detect only ferromagnetic materials. (True/False)

Answer 18

False

Question 19

What is one disadvantage of optical proximity sensor?

Answer 19

The object sensed must have a reflective surface.

Question 20

VA

Answer 20

Volt Ampage

Question 21

Calculation for the hold in Current

Answer 21

hold-in current= VA hold-in rating
______________
Coil voltage rating

Question 22

Calculation for inrush current

Answer 22

inrush current = VA inrush coiling
________________
Coil voltage rating

Question 23

How much current must flow to keep a relay latched?

Answer 23

Holding current

Question 24

What configuration ensures that when one device. is energized the other remains de-energized?

Answer 24

Electrical interlock

Question 25

A relay's make rating is often five times it's normal operating current? (True/False)

Answer 25

True

Question 26

Seal-in circuit

Answer 26

A method of maintaining a current flow after a momentary switch has been pressed and released.

Question 27

holding Contact

Answer 27

seal-in contact

Question 28

A seal-in circuit is usually parallel with a switch? (True/False)

Answer 28

True

Question 29

What maintains current flow to the control relay?

Answer 29

Holding Contact

Question 30

Electromagnetic Contactor

Answer 30

High power relay Current-handling above 15 A heavy duty contacts for switching industrial loads. designed with a stationary core and moveable armature

Question 31

How are electromagnetic contactors rated?

Answer 31

According to the size and type of load by National Electrical Manufacturers Association (NEMA)

Question 32

Electromagnetic contactors can be rated in horsepower. | true/False

Answer 32

True

Question 33

Overload relays and Circuit breakers can withstand repeated tripping and capable of reset.

Answer 33

Used in Excessive current flow in a industrial electronic circuit

Question 34

How are overload relays classified ?

Answer 34

as either thermal or magnetic

Question 35

Thermal overload relays

Answer 35

Respond to high temperature by overload current

Question 36

Magnetic Overload relays

Answer 36

React ONLY to excessive current and Not by temperature

Question 37

Most popular types of thermal relays are?

Answer 37

Metal alloy and Bimetal type

Question 38

Solenoid

Answer 38

an electro-mechanical device used in industrial control circuits. Commonin robots with hydraulic controls.

Question 39

How do solenoids differ from relays?

Answer 39

instead of controlling electrical power, solenoid valves generally control fluid power and have no contacts.

Question 40

Hydraulic fluid is used to rotate rotary actuators, besides filling hydraulic cylinders (True/ False)

Answer 40

True

Question 41

What are the ports called on a three-way solenoid valve?

Answer 41

Inlet, Outlet, exhaust.

Question 42

What devices are often used to operate control valves?

Answer 42

Solenoids

Question 43

Valve positions are used with feedback circuits (True /False)

Answer 43

TRUE

Question 44

What does TDR do?

Answer 44

Provide a delayed switching action

Question 45

What are 3 basic types of TDR?

Answer 45

Electromechanical, electropneumatic and electronic

Question 46

What are 2 basic types of counters?

Answer 46

Mechanical or Electronic

Question 47

2,9,13,16,20, 28,30