Motor Control 1

Question 1

Which of the following electrical industry pioneers invented the first practical AC motor?

Answer 1

Nikola Tesla

Question 2

A ? actuates manually-operated pilot devices..

Answer 2

Human Operator

Question 3

Automatically operated input devices are switches triggered by a change in a ? parameter, such as liquid level, pressure, fluid flow, and material temperature.

Answer 3

Process

Question 4

A relay is an electromagnetically controlled ? .

Answer 4

Switch

Question 5

The term interposing relay is used to describe a relay which enables the energy in a ? circuit to be switched by the ? circuit in a control system.

Answer 5

High-powered / low-powered

Question 6

The sealed current called ? implies that relays and solenoids are pulled in.

Answer 6

steady-state current

Question 7

When the contactor and ? are combined into a single device or separate devices that are wired together, the combination is a motor starter.

Answer 7

Overload

Question 8

Knife switch improvements including insulated handles and spring loaded blades mounted inside steel enclosures evolved into the modern ? .

Answer 8

Disconnect switch

Question 9

Overloads offer protection from excessive current flow to the switched load. When the contactor and overload are combined, the combination is a ? .

Answer 9

motor starter

Question 10

The power poles in the starter carry the motor current while other contacts, called ? are used for the control circuit.

Answer 10

auxiliary contacts

Question 11

An ? timer is a device with a preset time period between energizing the timer or applying the input signal and the action of the timer output contacts. During the timing period, no change occurs in the timer output contacts.

Answer 11

On-Delay

Question 12

Once initiated, ? contacts change state after a set time period has passed. Once the time has passed, all normally open timed contacts close and all normally closed timed contacts open.

Answer 12

DOE

Question 13

An ? timer is a device with a preset time period that starts after the input signal is removed. The timer output contacts change when the input signal or external trigger is applied, and the contacts remain in the changed state until after the timing period.

Answer 13

Off-Delay

Question 14

The off-delay timer function is also called a ?

Answer 14

DODE

Question 15

Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact prior to power being applied to the coil?

Answer 15

Closed

Question 16

Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact immediately after power is applied to the coil?

Answer 16

Closed

Question 17

Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact 30 seconds after power is applied to the coil?

Answer 17

Open

Question 18

Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact as soon as power is removed from the coil?

Answer 18

Closed

Question 19

Which timer is appropriate for keeping a motor starter energized after power is removed from the timer’s power input?

Answer 19

DODE

Question 20

What is the abbreviation for delay on de-energize?

Answer 20

DODE

Question 21

Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact prior to power being applied to the coil?

Answer 21

Closed

Question 22

Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact immediately after power is applied to the coil?

Answer 22

Open

Question 23

Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact 20 seconds after power is removed from the coil?

Answer 23

Open

Question 24

Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact 30 seconds after power is removed from the coil?

Answer 24

Closed

Question 25

Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact prior to the input of the external trigger switch?

Answer 25

Open

Question 26

Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact immediately after an input signal is received from the external trigger?

Answer 26

Closed

Question 27

Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact immediately after the input signal is removed from the external trigger?

Answer 27

Closed

Question 28

Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact 10 seconds after the input signal is removed from the external trigger?

Answer 28

Open

Question 29

A conveyor may be required to run for a period of time after a stop circuit is activated to assure the product is cleared from the conveyor, this would be an application for which type of timing relay?

Answer 29

DODE

Question 30

After a start signal is received to start a pump motor, a time delay is required to allow time for pre-lube to the pump. This would be an application for which type of timing relay?

Answer 30

DOE

Question 31

Which type(s) of motor control drawing(s) show the physical location of components in a circuit?

I. Ladder diagrams
II. Pictorial diagrams
III. Schematics
IV. Wiring diagrams

Answer 31

II. and IV.

Question 32

Schematic diagrams use graphic symbols to show ? between components and ? of an electrical circuit.

Answer 32

Connections / Functions

Question 33

Ladder diagrams show physical placements between the various components in a motor control drawing.

Answer 33

False

Question 34

What is the most widely used type of drawing for control circuit analysis?

Answer 34

Ladder Diagram

Question 35

Each horizontal line in a ladder diagram is identified as a ? .

Answer 35

Rung`