Electrical Final 1 Flashcards
What does NEMA stand for?
National Electrical Manufacturers Association
What does IEC stand for?
International Electrotechnical Commission
What are NEMA contactors sized using?
Horsepower
How are IEC relays sized?
Numbers
What are the rings of magnetism called around the wire?
Lines of flux.
What does BOY stand for?
Brown, Orange, Yellow
In BOY, what does Brown refer to?
Brown wire, 1 phase
In BOY, what does O stand for?
Orange wire, 2 Phase
In BOY, what does Y stand for?
Yellow wire, 3 Phase
What is the name of typical wire used in residential?
Romex
What is AWG?
American Wire Gauge.
What gauge is white romex?
14 AWG
What size breaker do we use for white romex wire?
15 AMP (Rated for 20 AMP)
What gauge is yellow romex wire?
12 AWG
What breaker do we use for yellow romex wire?
20 AMP (Rated for 25 AMP)
What gauge is orange romex wire?
10 AWG
What breaker do we use for orange romex wire?
30 AMP (Rated for 35 AMP)
What does NEC stand for?
National Electric Code
What ohmic value shows continuity?
0.1 Ohms or above
What is a load center?
The central location which distributes power.
What is the maximum number of receptacles on a 20 amp 120V circuit?
10
What color screw is used for hot connections?
Gold
What color screw is used for neutral connections?
Silver
What color screw is used for ground connections?
Green
Which side of a GFCI is protected?
Load side
Which side of a GFCI is not protected?
Line side
What does GFCI stand for?
Ground Fault Circuit Interuptor
What should you do before making any electrical repair?
Check for source voltage
What is bonding?
Landing neutral and ground connections together.
Difference to trip gfci
3-5 milli amps (mA)
What are the 5 components that create a circuit?
- Source Voltage
- Wire
- Switching Device
- Load
- Fuse/Breaker (OCPD)
What is a solenoid?
Electrical output device which converts electrical energy to linear mechanical power.
What do bold lines in a circuit’s diagram identify?
Power Circuit
What do light lines in a circuit’s diagram identify?
Control Circuit
What is needed to keep a motor running after pressing a momentary push button?
Normally Open Aux Tips in parallel with the button. AKA Normally Open Seal in Tips
What dictates what a power circuit does?
Control circuit
What is the symbol for an LED?
Diode with 2 arrows pointing out.
▶️|↗️↗️
What is a transformer used for?
Stepping down power (480➡️240➡️120)
What are the tongs on your meter used for?
Amps
What is ghost voltage?
Voltage created from magnetic energy generated by conductors, lights, etc. Can be measured in the air.
What is the symbol for a fuse?
⏛
How do you reverse a 3 phase motor?
Switch any 2 of the 3 wires/leads/phases
What is the minimum rating for DMMs in the mill?
Cat 3
What are the two types of current?
AC and DC
What are the 2 types of AC current?
Single phase and 3 phase
What is a black box for?
250VDC (Make sure to put DC)
What is a black and yellow striped box for?
Main Crane Disconnect
What is it called when a 3 phase connection/motor loses 1 phase?
Single Phasing
What consumes more power than anything else?
Motors
What are the 2 types of motor protection?
Overload(Thermals) and Fuses
How many Sinewaves are there per second on North America in AC current?
60
What fuel creates the most energy? (40%)
Coal
How is a 3 phase motor wired?
1 2 3
_ _ _
|4||5||6|
|7||8||9|
What does ESD stand for?
Electri Static Discharge
Which diagram shows the relationship between components but not their locations?
Ladder Diagram
What does OCPD stand for?
Over Current Protection Device
What protects a running motor?
Thermal Overloads
What protects a motor when starting?
Fuses
What shows length, width, and height in 1 view?
Pictorial View
What is a manual circuit?
A circuit which requires an actual person to actuate/energize it
Which part of a receptacle is hot? (Long or short)
Short
What is needed to increase magnetic fields?
Increased voltage, increased windings, add an iron core.
What does a diode do?
Allow current flow in 1 direction only.
What happens to amps when resistance increases?
Amps decrease
What is it called when magnetism is produced by current passing through a conductor?
Electromagnetism
What is the symbol for a ground?
⏚
What does NO stand for?
Normally Open
What does NC stand for?
Normally Closed
What should you do prior to installing a coupling to a motor?
Bump test the motor to verify direction of rotation.
What should be read with metering hot bus to neutral bus?
120VAC
How do you check a fuse with power off?
Ring it out for continuity
How do you check a fuse with power on?
Meter fuse for voltage. (Should show 0V)
What should you read if you meter 480VAC phase to ground?
277VAC
What is a red box for?
480VAC (Make sure you put AC)
Draw a motor starter circuit with a red light when running.
⏛x1. Start
| Stop | x2
| | —|– |
|__●–|–●__.__● ●___..__|/||
| MAux | | |
|___| |_____| |🔴|
