Deck 11: Power Factor

Question 1

The amount of capacitance needed can be determined by connecting a(n) ____, ammeter, and voltmeter to the circuit.

A) coulometer
B) megohmmeter
C) wattmeter
D) ohmmeter

Answer 1

C

Question 2

Assume that an inductor has an inductive reactance of 100 ohms and the wire has a resistance of 10 ohms. What is the impedance?

A) 10.5
B) 100.5
C) 110
D) 1000

Answer 2

B

Question 3

When the power factor of the plant is 1.0 (unity), the kilovarmeter reads ____.

A) 0
B) 50
C) 100
D) infinity

Answer 3

A

Question 4

Why are capacitors useful in power factor correction?

Question 5

In a three-phase circuit, the apparent power can be computed using this formula: VA = volts times ____ times the square root of three.

A) amps
B) resistance
C) inductance
D) capacitance

Question 6

Conductors in capacitor circuits must be rated no less than ____ percent of the current rating of the capacitor.

A) 90
B) 100
C) 120
D) 135

Question 7

A pure ____ element causes the voltage and current to be in-phase with each other.

A) conductive
B) resistive
C) inductive
D) capacitive

Question 8

A capacitor does not require a separate disconnect means if it is connected to the ____ side of the motor overload protective device.

A) switch
B) fuse
C) starter
D) load

Question 9

When testing capacitors, how is an ohmmeter used?

Question 10

When testing capacitors, if the capacitor is good, the microammeter should indicate ____ current.

A) zero
B) high
C) low
D) oscillating

Question 11

What are the three factors that determine the amount of induced voltage in an inductor?

Question 12

Apparent power is generally called ____.

A) volt amps
B) current voltage
C) circuit current
D) capacitance

Question 13

In a pure inductive load the current will lag the voltage by ____ degrees.

A) 45
B) 60
C) 90
D) 180

Question 14

How can you determine the power factor of a system?

Question 15

When two parallel feeders are installed to each of the synchronous condensers, the conductors can be sized for ____ the value of the required ampacity.

A) one-quarter
B) half
C) double
D) four times

Question 16

The ____ is a rotating electrical machine that has no electrical or mechanical loads connected to it.

A) synchronous motor
B) dc motor
C) ac generator
D) synchronous condenser

Question 17

When current begins to flow through a(n) ____, a magnetic field expands around the ____.

A) conductor
B) resistor
C) inductor
D) capacitor

Question 18

Most capacitors used in industry, especially for power factor correction, are called ____ capacitors.

A) conducting
B) dc
C) polarized
D) nonpolarized

Question 19

A dielectric test set must be used while testing capacitors. This device is often referred to as a ____ because of its ability to produce a high voltage or high potential.

A) DIVOLT
B) DIPOT
C) HIPOT
D) HIVOLT

Question 20

What rules apply when you are using parallel feeders?