Electricity

Question 1

How is an ion made?

Answer 1

By adding or pulling away electrons

Question 2

What letter indicates electrical charge?

Answer 2

Q

Question 3

Coulomb (C)

Answer 3

Unit for measuring electrical charge

Question 4

Quantity of electrons in one coulomb

Answer 4

1C = 6.214 x 10^18 electrons

Question 5

Rate at which current travels with 1 coulomb

Answer 5

1A/second

Question 6

Conductors used in automotive

Answer 6

Copper
Aluminum

Question 7

Out of copper and aluminum, which conductor is most preferred and why?

Answer 7

• Copper
  1. Better conductivity
  2. More flexible
  3. Less corrosive

Question 8

In what instances would aluminum be used?

Answer 8

Where weight is a concern
It’s lighter & cheaper than copper

Question 9

Current indicated by what letters?

Answer 9

I or A

Question 10

What does (I) stand for? (Current)

Answer 10

Intensity

Question 11

Voltage indicated by what letters?

Answer 11

E or V

Question 12

What does (E) stand for? (Voltage)

Answer 12

electromotive force

Question 13

2 types of voltage sources?

Answer 13

DC & AC

Question 14

Characteristics of DC voltage wave?

Answer 14

Square or triangle that don’t cross the zero line

Question 15

Characteristics of AC voltage wave?

Answer 15

Sine wave

Question 16

How is AC voltage created?

Answer 16

By moving a magnet up and down in a coil of wire

Question 17

Difference between a wiring diagram and a schematic?

Answer 17

Wiring diagram is colored and provides more of a realistic visualization

Question 18

Series circuit characteristics

Answer 18

V = V1 + V2 + V3 + V4
A = A1 = A2 = A3 = A4
R = R1 + R2 + R3 + R4

Question 19

Parallel circuit characteristics

Answer 19

V = V1 = V2 = V3 = V4
A = A1 + A2 + A3 + A4
1/RT = 1/R1 + 1/R2 + 1/R3 + 1/R4

Question 20

Relay description

Answer 20

Coiled soft iron core controlled by a switch that creates a magnetic field exerting force to close another switch

Question 21

4 connection points of a standard relay ((+) - (-))

Answer 21

Control current 86 & 85
Main current 30 & 87 or (and 87A)

Question 22

3 types of relays

Answer 22

Make-contact relay
Break-contact relay
Change-over relay

Question 23

Make-contact relay

Answer 23

Closes circuit when when energized

Question 24

Break-contact relay

Answer 24

Breaks circuit when when energized

Question 25

Change-over relay

Answer 25

Opens a circuit and closes another

Question 26

How do you recognize a change-over relay?

Answer 26

Extra main current connection (87A) Symbol on housing

Question 27

Resistivity of wire depends on?

Answer 27

Length Cross-sectional area Resistivity (material)

Question 28

Resistivity of wire increases when

Answer 28

Cross-sectional area decreases Added length

Question 29

Control current points of a relay

Answer 29

86 & 85

Question 30

Main current points of a relay

Answer 30

30 & 87 or (and 87A)

Question 31

Visual representation of a magnetic field that depicts direction and strength

Answer 31

Lines of induction

Question 32

To determine direction of a magnetic field

Answer 32

Right hand method

Question 33

Right hand method indicates:

Answer 33

Thumb current direction Fingers represent direction of magnetic field lines

Question 34

Direction of current flow: Cross

Answer 34

Current moves into wire from that end

Question 35

Direction of current flow: Dot

Answer 35

Current flows out from that end

Question 36

Proportion of electromagnetic force

Answer 36

5 turns & 1A = 1 turn & 5A

Question 37

Symbol of PM motor

Question 38

How do you change the direction of a PM motor rotation

Answer 38

Reversing the supply voltage

Question 39

Source voltage of a battery

Answer 39

Battery voltage when no current is flowing

Question 40

Terminal voltage of battery

Answer 40

Battery voltage when current is flowing

Question 41

Why does the voltage of a battery decrease over time?

Answer 41

Lead plates in the battery deteriorate over time increasing resistance within the battery

Question 42

Advantages of a battery tester

Answer 42

* Battery doesn't need to be charge * Battery doesn't need to be disassembled * It's a passive method of charging (No sparks or risk of damaging electronic components)

Question 43

When should you test the battery with the battery tester?

Answer 43

When the engine is off

Question 44

If the engine is running, what should you do when using the battery tester?

Answer 44

Switch lights on and off 1 minute each

Question 45

Components of the starting system

Answer 45

1. Battery 2. Start switch 3. Starter motor 4. Flywheel ring gear

Question 46

Main components of starter

Answer 46

* Solenoid * Starter drive shift lever * Electric motor

Question 47

Components of starter solenoid

Answer 47

* Pull-in & hold-in coils * Iron core * Returning spring * contact plate * 3 connections (revise later)

Question 48

How many phases are there in the operation of the starter solenoid?

Answer 48

3

Question 50

1st phase of starter solenoid operation

Answer 50

1. Coils create magnetic field 2. Iron core gets pulled in & shift lever actuates simultaniously

Question 51

2nd phase of starter solenoid operation

Answer 51

1. Solenoid switches on main current to motor 2. Hold-in coil remains activated to keep iron core in place 3. current no longer running through pull-in coil

Question 52

3rd phase of starter solenoid operation

Answer 52

1. Ignition switch key is released turning current off 2. A spring pushes iron core back to starting position

Question 53

When is the most force required the most during the operation of the starter solemoid?

Answer 53

When both the movement of the lever & engagement of the pinion gear occur in the first phase

Question 54

How many volts of dc can kill you?

Answer 54

50 amps

Question 55

Are the coils of the starter solenoid connected in series or parallel?

Answer 55

Parallel

Question 56

Electrical operation during the 1st phase of operation of the starter solenoid?

Answer 56

* Current runs through pull-in coil via armature to ground * Current through hold-in coil runs via housing of starter motor to ground

Question 57

Electrical operation during the 2nd phase of operation of the starter solenoid?

Answer 57

* Main contacts are connected & large current runs through armature * No current runs through the pull-in coil to prevent solenoid from overheating when restarting for lengthy periods

Question 58

Electrical operation during the 3rd phase of operation of the starter solenoid?

Answer 58

No current flows

Question 59

Draw elctric diagram of starter solenoid

Question 60

5 locations a fault may occur in the starting system

Answer 60

1. Battery 2. Starter motor 3. Ignition Switch 4. Fuse 5. Wiring

Question 61

4 connections of starter motor

Answer 61

1.