Electrical

Question 1

Resistive resistance is:

Answer 1

Resistance that remains constant.

Question 2

Reactive resistance is:

Answer 2

Resistance found in devices with a magnetic coil, which creates a magnetic field in direct opposition to the volt, creating back-emf.

Question 3

Emf:

Answer 3

Electromotive force

Question 4

Ohms law:

Answer 4

E=I×R, the relationship between Volt, Current and Resistance

Question 5

Continuity

Answer 5

Describes a complete path for electron movement from one point to another.

Question 6

Power equation

Answer 6

P= IxE watt=amp x volt

Question 7

Voltage drop (VD)

Answer 7

The loss of emf (volt) between 2 wires or across a load.

Question 8

Causes of VD

Answer 8

An electrical load, loose wire or undersized conductor.

Question 9

Ampacity

Answer 9

The amount of current a conductor can safely carry with out overheating.

Question 10

Volt and resistance determine the mount if electron flow. Watt measures. . .

Answer 10

The rate of energy conversion

Question 11

Self Inductance

Answer 11

When varying lines of magnetic flux induce an EMF in a coil, the coil has self inductance.

Question 12

Mutual Inductance

Answer 12

When varying lines of magnetic flux induce an EMF in an adjacent coil, the coils have mutual Inductance. Based of transformers.

Question 13

Inductive Reactance

Answer 13

A type of resistance that us produced when a coil of wire carries an alternating current.

Question 14

LRA

Answer 14

Locked Rotor Amp, the amp draw of a motor on start up

Question 15

FLA

Answer 15

Full Liad Amp, the Amp draw of a motor at peak torque and hp. Full load.

Question 16

RLA

Answer 16

Rated Load Amp, the Amp draw of a compressor when operating at its rated load, rated voltage and rated frequency.

Question 17

Resistance is used to measure for

Answer 17

An electrical short
A grounded connection
An open
A higher than normal resistance

Question 18

Capacitors are rated in

Answer 18

Farads/ microfarads

Question 19

Define power

Answer 19

The rate at which work is being done

Question 20

True power

Answer 20

The amount of power actually used by a load (W)

Question 21

Reactive power

Answer 21

The power absorbed and returned by the circuit without doing any useful work. (VAR)

Question 22

Apparent power

Answer 22

The total power (True + Reactive) in the circuit (VA)

Question 23

Inductive reactance

Answer 23

Resistance caused by magnetic fields, like a motor

Question 24

Capacitive reactance

Answer 24

Resistance caused by the shortage of electrons

Question 25

Power factor

Answer 25

PF = True power (W) / Apparent Power (VA) The lower the power factor, the greater the amount of current that must be carried to handle the load.

Question 26

Phase splitting

Answer 26

Start and run windings have diff Inductance values, the current flowing through the start winding is out of phase with the run winding, split phase causes a rotating magnetic field in the stator causing the rotator to start turning.

Question 27

Split phase motor

Answer 27

A single phase induction motor used in applications that operate in the fractional hp range

Question 28

Variable Frequency Drive (VFD)

Answer 28

Control circuit that modifies the frequency of signals to ac motors. Uses a rectifier to change 60hz ac to DC then back to AC at a different frequency.

Question 29

An electrical property that opposes the current change in an AC circuit.

Answer 29

Inductance

Question 30

When too much current flows through an electrical circuit.

Answer 30

Overload

Question 31

A unit of electrical power, equivalent to the watt.

Answer 31

Volt-amp (VA)

Question 32

Thermistor

Answer 32

Regulates the flow of current by changing its resistance based on heat.

Question 33

Bonding

Answer 33

A continuous electrical connection of all the metal parts in an electrical system.

Question 34

Short circuit

Answer 34

When current is unintentionally routed around a component or load instead of through it.

Question 35

Diode

Answer 35

A solid state device that allows DC current to flow in one direction.

Question 36

Anode

Answer 36

The positive side of a diode

Question 37

Cathode

Answer 37

The negative side of a diode

Question 38

Transducer

Answer 38

A device that converts the input signal from one form of energy to an output signal of another form of energy

Question 39

Diac

Answer 39

A diode for AC, allows current to flow in both directions

Question 40

Rectifier

Answer 40

An electronic circuit that converts AC to DC

Question 41

Inverter

Answer 41

Converts DC to AC

Question 42

Thermistor

Answer 42

A solid state device that changes its resistance as the temp of the thermistor changes.

Question 43

NTC vs PTC

Answer 43

Negative temp coefficient= thermistor decreases resistance as temp increases Positive temp coefficient = thermistor increases resistance as temp increases.