問題一覧
1
All of the customer owned, three-phased motors on a distribution circuit spin in the same direction
true
2
What is used to measure reactive power in a pure inductive circuit
- VARs
3
Frequency
- The number of time that a generator rotates
4
In a series circuit what remains constant throughout the the circuit?
- Amperage
5
In a open circuit, current will not flow
- True
6
If the phase voltage (phase-to-ground) of a Wye system is 12000 volts, what is the line voltage (phase-to-phase)?
- 20800 volts
7
In a parallel circuit, what remains constant throughout the circuit?
Voltage
8
What is an advantage of a three-phase system over a single-phase system?
- A 73% increase in power
9
Why are capacitors installed on power lines?
- To increase apparent power?
10
Induction only occurs?
- When the magnetic field expands and collapses
11
Phasing out is necessary when?
- Equipment is out dated and causes power factor problems
12
A sine wave can be defined as?
- A graphical representation of what is happening to voltage in an AC circuit over time
13
Consider that a phase sequence into a motor is CBA and the motor is rotating clockwise, which of the following sequences will cause the motor to rotate counterclockwise?
- ABC
14
A parallel circuit is a circuit where?
- There is more than one path for current to flow
15
When current is in phase with voltage..
- They both rise and fall at the same time
16
A short circuit is defined as
A circuit where the load has been bypassed
17
Four wire Wye-systems are the overall preferred system by utility companies because?
- it’s more reliable in regard to fault protection
18
RMS stands for root mean square and is?
- a value of AC voltage that will produce the same amount of power as a like value of DC
19
Delta and three-wire Wye-systems look the same in the field?
- true
20
The strength of generated voltage depends on three things. Which of the following is one of them?
- The strength of the magnetic field
21
What effect do coil jumpers have on a power line circuit?
They increase inductance
22
A series circuit is a circuit where?
- There is only one path to follow
23
Rotating a magnet near a conductor produces a current because?
The electrons are repelled and attracted due to the law of charges
24
Inductance can be increased by?
Coiling the conductor
25
What is recommended to take place before working on a corner pole to ensure that the jumpers will be reconnected properly?
- The jumper connections should be recorded