J MCC Motor Control Circuits

Question 1

Horsepower is defined as

Answer 1

Moving a certain weight over a certain distance in one minute (e.g, 33,000 pounds lifted 1 foot in 1 minute equals 1hp)

Question 2

It takes 746W of electric power to equal

Answer 2

1 HP

Question 3

A over current protection device with a link that melts and opens the circuit on an over current condition

Answer 3

Fuse

Question 4

A connection is made when 3 ends of separate phases are connected together creating a common wire

Answer 4

Wye

Question 5

A…… is a metal enclosed distribution system of….. available in prefabricated sections

Answer 5

Busways, Busbars

Question 6

Contain over current protection devices for lighting appliances and power distribution centers

Answer 6

Panel Boards

Question 7

Receives incoming power and delivers it to control circuit and to loads

Answer 7

Motor Control center

Question 8

Device that protects transformers and other electrical equipment from power surges caused by lightning

Answer 8

Lightning arrestor

Question 9

Used first to stop and start motors…before magnetic motor starters

Answer 9

Knife switches

Question 10

Two contractors that are connected in such a way that both sets of contacts cannot be closed at one time

Answer 10

Mechanical interlock contractors

Question 11

A device used only periodically to remove electrical circuits from there supply source

Answer 11

Disconnect

Question 12

Contractors with added overload protection device

Answer 12

Manual starter

Question 13

An overload relay which resets automatically

Answer 13

Bimetallic relay

Question 14

Solder-pot relay aka

Answer 14

Melting-alloy overload relay

Question 15

When a device receives too little voltage to work and requires a manual restart

Answer 15

Low- voltage protection

Question 16

When too much electricity is in the circui,t this happens, to save the wires, devices and limit the damage

Answer 16

Overload release

needs manual restart and wait for circuit to cool down

Question 17

Rotary- action selector switch
Manually controls speed
changes the direction of motors

Answer 17

Drum Switch
(does not provide overload protection)

Question 18

ON/Off With thermal overload is a ____ switch

Answer 18

Toggle switch (operates on a solder-pot principle)

Question 19

Motors and circuits involves ____& ____ hazards

Answer 19

Mechanical and electrical hazards

Question 20

Heather element and N.C. Contacts are wired in series with the line to the motor is what principle

Answer 20

Solder-pot principal

Question 21

A device that operates on the reduction or failure of voltage, but not prevent a re-establishment of voltage

Answer 21

Low-voltage release