$ Chapter 1
1. The
_________ is the basic building block of the universe.
2. The 3
principal parts of an atom are the ________, the ________ and the ________.
3. The
Proton has a ________ charge.
4. The
Electron has a ________ charge.
5. The
Neutron has ________ charge.
6. The
proton and the neutron combine to form the ________ of an atom.
7. An
electron is ________ times larger than a proton.
8. The
proton weighs about ________ times more than an electron.
9. The
proton is MUCH more massive than the electron. (T or F)
10. The Law
of Charges states that ________ charges attract and ________ charges repel.
11. The Law
of Centrifugal Force states that _______________________________.
12. The first
shell of an atom can have a maximum of ________ electrons.
13. The
second shell of an atom can have a maximum of ________ electrons.
14. The third
shell of an atom can have a maximum of ________ electrons.
15. The
fourth shell of an atom can have a maximum of ________ electrons.
16. The
formula for the number of electrons in a shell is __________________ (where
N=shell).
17. The outer
shell of an atom is the ________ shell.
18. Any
electrons in the valence shell are known as ________ electrons.
19. The
Valence Shell of an atom cannot hold more than ________ electrons.
20. A
Conductor has how many electrons in its Valence Shell ?
21. Which is the
best conductor of Silver, Copper and Aluminum?
22. Why is
copper the most common conductor?
23. Which is
the best insulator of Silver, Copper and Aluminum?
24. Electricity
can be defined as ____________________________________.
25. Insulators
have ____________ valence electrons.
26. Centrifugal
force is proportional to __________ and _________.
27. What are
the 3 subatomic parts of atoms and what charge does each carry?
28. How many
times larger is an electron that a proton?
29. The
weight of a proton is how many times heavier than an electron?
30. State the
Law of Charges
31. What
force keep the electron from falling into the nucleus of an electon?
32. Materials
that make the best conductors have how many valence electrons?
33. Materials
that make the best conductors have how many valence electrons?
34. Electricity
may be defined as ________________________________.
$ Chapter 2
1. What is a
Coulomb?
2. Define
the term AMPERE (AMP).
3. Define
the term VOLTAGE.
4. Define
the term OHM.
5. Define
the term WATT.
6. An
electric heating element has a resistance of 16 ohms and is connected to a
voltage of 120 volts. How much current (amps) will flow in the circuit?
7. How many
watts of heat are being produced by a heating element with R=16 ohms and E=120
volts?
8. A
240-volt circuit has a current flow of 20 amps. What is R ?
9. An
electric motor has an apparent resistance of 15 ohms. If a current of 8A is
flowing through the motro, what is the connected voltage?
10. E=240,
R=8, what is I?
11. E=240,
R=8, what is W?
12. W=5000,
E=240, what is I?
13. W=5000,
E=120, what is I?
14. Is it
less expensive to use 240V for heating rather than 120V? Explain.
$ Chapter 3
1. What type
of meter has a high resistance connected in series with the meter movement?
2. How is a
voltmeter connected into the circuit?
3. If a
voltmeter has a resistance of 5000 ohms per volt, what is the resistance of the
meter when it is set on the 300-volt range?
4. What is
the advantage of using a voltmeter that has a high impedance as opposed to a
low-impedance meter?
5. What is
an analog meter?
6. Why must
an ammeter be connected in series with the load?
7. What device
is used to change the scale values of an AC ammeter?
8. What is
meant by the term "inline" ammeter?
9. A
clamp-on ammeter has three turns of wire wrapped around the movable jaw. If the
meter is indicating a current of 15 amps, how much current is actually flowing
in the circuit?
10. List the
three steps for reading a meter.
11. What type
of meter contains its own internal power supply?
12. What
precaution must be taken when using an ohmmeter?
$ Chapter 4
1. List the
three types of electrical circuits.
2. What is
the major characteristic of the series circuit?
3. List the
three basic rules for series circuits.
4. What is
the major characteristic of a parallel circuit?
5. List the
three basic rules for the parallel circuit.
6. What type
of circuit is used most often in industry and the home?
7. What type
of circuit is used the least in industry and the home?
8. Three
resistors valued at 300 ohms, 200 ohms, and 600 ohms are connected in series.
What is their total resistance?
9. Three
resistors valued at 300 ohms, 200 ohms, and 600 ohms are connected in parallel.
What is their total resistance?
10. How are
fuses and circuit breakers connected in a circuit and why are they connected
this way?
$ Chapter 5
1. What is
an alternator?
2. What
controls the output voltage of an alternator?
3. What
controls the frequency of the alternator?
4. How many
degrees out of phase with each other are the voltages of a three-phase system?
5. What are
the two major types of three-phase connections?
6. List the
rules concerning line and phase values of current and voltage in a wye
connection.
7. List the
rules concerning line and phase values of current and voltage in a delta
connection.
8. In a
high-leg delta-connected system, what is the voltage between the high leg and
neutral?
9. What type
of three-phase transformer connection uses only two transformers?
10. How many
degrees out of phase are the voltages of a single-phase system?
11. A
two-conductor romex cable contains three wires. Which wire is not counted and
why?
12. What type
of circuit breaker is used to make a 240-volt connection?
13. Where
does the grounding conductor connect in a panel?
14. In what
two electrical units are fuses rated?
15. It has
been calculated that a 290-amp fuse is needed to protect the circuit supplying
an air-conditioning compressor. What standard rating of fuse should be used?
16. It has
been calculated that a 290-amp fuse is needed to protect the circuit supplying
an air-conditioning compressor. What size fuse disconnect will be used for the
fuse?
17. What is a
dual-element fuse?
$ Chapter 6
1. Name four factors that
determine the resistance of wire,
2. A wire has a diameter of .057
inches. What is its circular mil area?
3. What is a mil-foot of wire?
4. When the temperature of wire
increases, does its resistance increase or decrease?
5. What determines the voltage
rating of wire?
6. What two factors determine the
amount of voltage rating a certain type of insulation will have?
7. How much resistance does 75
feet of #24 AWG wire have?
8. If a current of 4 amps flows
through the wire in question #7, how much voltage will be dropped by the wire?
$ Chapter 7
1. Name the three basic types of
alternating-current loads.
2. What type of load always has
its voltage and current in phase with each other?
3. In a pure-inductive circuit,
how many degrees out of phase is the current with the voltage?
4. Does the current lead or lag
the voltage in question #3?
5. What electrical value is used
to measure inductance?
6. What is inductive reactance?
7. What electrical value is used
to measure the total opposition to current flow in an AC circuit?
8. What is power factor?
$ Chapter 8
1. What three factors determine
the capacitance of a capacitor?
2. What is the dielectric?
3. In what type of field is the
energy of a capacitor stored?
4. In a pure-capacitive circuit,
how many degrees are the current. and voltage out of phase with each other?
5. Does a capacitive current lead
the voltage or lag the voltage?
6. What limits the current in a
capacitive circuit?
7. Name two common types of
capacitors used in the air-conditioning field.
8. What type of capacitor is
generally used as the running capacitor on many air-conditioning compressors?
9. What is the advantage of an AC
electrolytic capacitor?
10. What is the disadvantage of
an AC electrolytic capacitor?
$ Chapter 9
1. What is a split-phase motor?
2. What are the three basic types
of split-phase motors?
3. Explain the difference in
construction of run windings and start windings.
4. How many degrees out of phase
should be current in the start winding with the current in the run winding to
develop maximum starting torque?
5. What type of capacitor is
generally used with a capacitor start induction-run motor?
6. Can the micro-farad value of
this capacitor be increased to improve starting torque?
7. What type of capacitor is used
with a permanent-split capacitor motor?
8. Does the capacitor of a
capacitor start induction-run motor help correct power factor?
9. If necessary, can an AC
electrolytic capacitor of higher voltage rating be used as the starting
capacitor?
10. What is a centrifugal switch
used for?
$ Chapter 10
1. What is a shading coil?
2. What determines the
synchronous speed of a shaded-pole motor?
3. In general, how is the
direction of a shaded-pole induction motor reversed?
4. What type of rotor does the
shaded-pole motor contain?
5. Name two advantages of the
shaded-pole motor over the split-phase induction motor.
$ Chapter 11
1. Name two ways of changing the
speed of a rotating magnetic field.
2. How does the consequent pole
motor change speed?
3. Name a disadvantage of the consequent
pole motor.
4. Name an advantage of a
consequent pole motor.
5. How many steps of speed are
common to a multi-speed fan motor?
6. Refer to figure 11-3. Explain
what would happen to motor operation if the winding between low and medium
should become open.
7. What is an advantage of the
multi-speed fan motor over the consequent pole motor?
8. What is a disadvantage of the
multi-speed fan motor when compared to the consequent pole motor?
9. How much wire resistance is
common for the run winding of most split-phase motors?
10. How much wire resistance is
common for the multi-speed fan motor?
$ Chapter 12
1. What are the three basic types
of three-phase motors?
2. Name three factors that
produce a rotating magnetic field.
3. What is synchronous speed?
4. What two factors determine the
synchronous speed of a three-phase motor?
5. How is the direction of
rotation of a three-phase motor changed?
6. What is the synchronous speed
of a four-pole motor when connected to a 60-Hz line?
7. A dual-voltage three-phase
motor has a current draw of 50 amps when connected to a 240-volt line. How much
current will flow if the motor is connected for operation on 480 volts?
8. If the stator windings of a
three-phase motor are connected for operation on high voltage, will the
windings be connected in series or parallel?
9. If a dual-voltage motor is
connected for operation on low voltage, and the motor is then connected to high
voltage, will the motor operate at a faster speed?
10. Why does a dual-voltage motor
draw less current when connected to low voltage than it does when connected to
high voltage?
$ Chapter 13
1. What three factors determine
the amount of torque produced by an AC induction motor?
2. Why does an AC induction motor
draw more current when starting than it does when running?
3. Why does the current flow to
the motor increase when load is added to the motor?
4. What does the code letter
found on the nameplate of the motor indicate?
5. At what degree angle between
the stator current and the rotor current is the maximum torque developed?
6. What type of squirrel cage
rotor has the highest starting torque?
7. What type of squirrel cage
rotor has the best speed regulation?
8. Why can an induction motor
never operate at synchronous speed?
9. What does the locked rotor
current of a motor indicate?
10. The nameplate of a squirrel
cage motor indicates that the motor has a full-load speed of 875 RPM. How many
poles per phase does the motor have?
$ Chapter 14
1. How many slip rings are
located on the shaft of the rotor of a wound rotor induction motor?
2. What is the purpose of the
slip rings?
3. Name two advantages of the
wound rotor motor over the squirrel cage motor.
4. What two factors determine the
amount of current flow in the rotor of a wound rotor motor?
5. What does the dashed line
drawn between the three resistors shown in figure 14-2 indicate?
6. Why is the starting torque of
a wound rotor induction motor higher than the starting torque of a squirrel
cage induction motor?
7. The stator of a wound rotor
motor has a synchronous speed of 1200 RPM when connected to a 60-Hz line. How
many poles per phase are there in the rotor? 8. Refer to figure 14-5. Describe
what would happen in this circuit if coil "SI" should be open when the
motor started.
9. Refer to figure 14-5. Describe
what would happen in this circuit if coil "TR2" should be open when
the motor is started.
10. Refer to figure 14-5.
Describe what would happen in this circuit if holding contact "M"
should become stuck together when the motor is started and not open.
$ Chapter 15
1. Name three characteristics of
a synchronous motor that the squirrel cage induction motor and the wound rotor
motor do not have.
2. What is an amortisseur
winding?
3. How many slip rings are
located on the shaft of a synchronous motor?
4. How many slip rings are
located on the shaft of a wound rotor induction motor?
5. Is a synchronous motor started
with DC excitation voltage applied to the rotor?
6. What is the field discharge
resistor used for?
7. A synchronous motor has an
eight-pole stator. What will be the speed of the rotor when it is under full
load?
8. How is it possible to know
when a synchronous motor has normal excitation applied to its rotor?
9. How can a synchronous motor be
made to have a leading power factor?
10. What is a synchronous
condenser?
$ Chapter 16
1. What are the two basic types
of industrial overload units?
2. What is the advantage of the
bimetal type of industrial overload unit?
3. Industrial overload units are
divided into two sections. What are they?
4. At what percentage of
full-load motor current are overload units generally set to trip?
5. When using an industrial type
of overload unit, what are the contacts connected in series with?
6. What is the difference between
the two types of small overload units'?
7. In the small overload unit
which does not contain a heater, what is used to sense the current flow through
the motor?
$ Chapter 17
1. What is a solenoid?
2. What type of relays contain a
shading coil?
3. What purpose does the shading
coil serve?
4. What is the movable part of a
relay called?
5. Why is the core material of a
relay laminated?
6. What are eddy currents?
7. What effect do eddy currents
have on a relay?
8. Why are contact surfaces
curved?
9. What is the difference between
a relay and a contactor?
10. What is the difference
between a contactor and a motor starter?
$ Chapter 18
1. What electronic component is
used to control the output of a solid-state relay used to control a DC voltage?
2. What electronic component is
used to control the output of a solid-state relay used to control an AC
voltage?
3. Explain opto-isolation.
4. Explain magnetic isolation.
5. What is meant by zero
switching?
$ Chapter 19
1. What is
an isolation transformer?
2. Define a
step-up transformer.
3. Define a
step-down transformer.
4. The
primary of a transformer is connected to 120 volts AC. The secondary has a
voltage of 30 volts and is connected to a resistance of 5 ohms. How much
current will flow in the primary of the transformer?
5. What is
the amount of Control voltage used in most residential air-conditioning
systems?
6. What is
the amount of control voltage used in most industrial air-conditioning systems?
7. What is
the color of the primary leads of most control transformers used for
residential service?
8. How many
primary windings are generally contained in an industrial control transformer?
9. What is
the turns ratio of each of these primary windings as compared to the secondary
winding?
10. When an
industrial control transformer is to be operated on 480 volts, are the primary
windings connected in parallel or series?
$ Chapter 20
1. What are
the four types of starting relays?
2. On what
type of motor is it necessary to use a starting relay'?
3. What
principle is used to operate the hot-wire relay?
4. What
principle is used to operate the current relay'?
5. What type
of starting relay does not sense motor current to operate?
6. What type
of starting relay can be used for overload protection for the motor?
7. What type
of motor can the potential relay be used with'?
8. Is the
start contact of a hot-wire relay open or closed when power is first applied to
the motor'?
9. Is the
start contact of a current relay open or closed when power is first applied to
the motor'?
10. Refer to
the circuit shown in figure 20-4. What would happen if the coil of the current
relay were open when the thermostat connected power to the motor circuit?
$ Chapter 21
1. What two
types of small AC motors are used with variable-voltage speed control?
2. Why are
these two types of motors used?
3. Name two
methods of variable-voltage control for small AC motors.
4. What
solid-state device is used to control the voltage applied to the motor?
5. Why is it
necessary to use only controllers designed for use with inductive loads?
6. Name a
method other than variable voltage used to control the speed of small AC
motors.
$ Chapter 22
1. What type
of motor is used to operate the timer?
2. Why is
one of the motor leads brought outside the timer?
3. Name two
ways of connecting the defrost timer.
4. What
function does the defrost heater perform?
5. To which
terminal is the pigtail lead of the timer motor connected if the timer is to
operate continuously?
$ Chapter 23
1. What is a
thermostat?
2. What is
the advantage of an open-contact thermostat?
3. What is
the disadvantage of an open-contact thermostat?
4. What is
the advantage of a mercury thermostat?
5. What is
used to provide a snap action for the contacts in an open-contact type of
thermostat?
6. What is
used to provide a snap action for the mercury thermostat?
7. What
method of sensing temperature is often used with line voltage thermostats?
8. What is a
programmable thermostat?
9. What is
the advantage of the programmable thermostat?
10. What is a
differential thermostat?
11. What are
differential thermostats generally used to control?
12. What is
antifreeze protection in reference to a differential thermostat?
13. What is
the advantage of a low-voltage thermostat over a line voltage thermostat?
14. What is
the purpose of the heat anticipator?
15. How is
the setting of the heat anticipator generally determined?
$ Chapter 24
1.
What
device is used to construct most of the pressure switches used in the
air-conditioning field?
2.
What
type of contact is used with a high-pressure switch?
3.
What
type of contact is used with a low-pressure switch?
4.
Where
in the refrigerant system is the high-pressure switch connected?
5.
Where
in the refrigerant system is the low-pressure switch connected?
$ Chapter 25
1. What is a
common name for the airflow switch?
2. What
function does the airflow switch perform in a circuit?
3. What is
interlocking in a control circuit?
$ Chapter 26
1. What is a
humidistat?
2. What are
the two most common materials used to sense humidity?
3. What type
of control is often used to interlock the humidifier with the blower?
$ Chapter 27
1.
Why
do some fan switches permit the temperature at which the switch will turn off
to be set?
2.
What
type of sensing device do most fan switches use to determine when the
temperature is high enough to start the blower fan?
3.
What
type of contact arrangement is used for switches that control the speed of a
condenser fan motor?
4.
What
is the most common use for a high-limit switch?
5.
Why
is the blower fan not connected in series with the limit switch?
$ Chapter 28
1.
How
can the actual amount of useful oil pressure in a condenser be found?
2.
What
is the function of the current-limiting resistor?
3.
Why
is the current-limiting resistor center tapped'!
4.
Does
a high enough oil pressure open the differential pressure switch contacts or
close them?
5.
What
is the function of the heater?
6.
Explain
the sequence of events that take place if the oil pressure does not become
great enough to disconnect the heater circuit.
7.
What
is the cut-in point?
8.
What
is the cut-out point?
9.
Is
the timer circuit connected in series with the motor starter coil?
10. Are the control contacts connected
in series with the motor starter coil?
$ Chapter 29
1.
What
is a solenoid valve?
2.
Why
is it important not to reverse the connection of the inlet and outlet side of a
solenoid valve?
3.
What
is used to cause the plunger to close when the solenoid coil is de-energized?
4.
What
is the function of a 4-way reversing valve?
5.
What
is the function of the pilot valve?
6.
What
is the function of the main valve?
7.
What
is actually used to change the position of the main valve from one setting to
another?
1.
What
is short cycling?
2.
What
is used to provide the timing operation for the short-cycle timer?
3.
What
type of contacts are used in the short-cycle timer?
4.
How
many and what type of contacts must the holding relay have?
5.
What
does the dashed line drawn between the two sets of timer contacts represent?
$ Chapter 31
1.
Should
a metal bar be heated or cooled to make it expand?
2.
What
type of metal remains in a liquid state at room temperature?
3.
How
is a bimetal metal strip made?
4.
Why
are bimetal strips often formed into a spiral shape?
5.
Why
should electrical contacts never be permitted to open or close slowly?
6.
What
two factors determine the amount of voltage produced by a thermocouple?
7.
What
is a thermopile?
8.
What
do the letters RTD stand for?
9.
What
type of wire are RTDs made of?
10. What material is a thermistor made
of?
11. , Why is it difficult to measure
temperature with a thermistor?
12.
, If
the temperature of a NTC thermistor increases, will its resistance increase or decrease?
13. How can a silicon diode be made to
measure temperature?
14.
Assume that a silicon diode is being used as a temperature
detector. If its temperature increases, will its voltage drop increase or
decrease?
15. What is an above- and below-ground
power supply?
$ Chapter 32
1.
What are the two basic types of motor controls?
2.
Define a schematic diagram.
3.
Define a wiring diagram.
4.
Components used for the function of stop are generally
wired ______________ _______________ and connected in __________.
5.
Components used for the function of start are generally
wired _______________ ______________ and connected in _________.
6.
When reading a schematic diagram, are the components shown
in their energized or de-energized position?
7.
What does this symbol represent? ![]()
8.
What does this symbol represent? ![]()
9.
What does a dashed line drawn between components represent?
10.
What is an auxiliary contact?
$ Chapter 33

Refer to circuit 33-1 for the
following questions.
1.
Explain
the action of the circuit if the thermostat should fail to operate.
2.
Explain
the action of the circuit if FR contacts should become shorted together.

Refer
to circuit 33-7 for the following questions.
3.
Explain
the action of the circuit if the overload (OL) contact should open.
4.
Explain
the action of the circuit if the pressure switch contacts should become
shorted.
5.
Explain
the action of the circuit if the CR coil should open.
$ Chapter 34
1.
What
is the purpose of a pilot light?
2.
Why
is it necessary to be certain that the gas is ignited at the main burner on a
call for heat by the thermostat?
3.
What
is a thermocouple?
4.
What
is a thermopile?
5.
Why
must the pilot control valve be reset manually if it should open?
6.
Explain
how a "fire eye" works.
7.
Explain
the operation of a "flame rod."
8.
What
is a common amount of voltage applied to an electric spark ignitor?
9.
Why
must a ground wire be connected between the direct spark-ignition control
module and the burner head?
10. What is the advantage of
electric-spark ignition over pilot-light ignition?
$ Chapter 35
1.
What
is the function of the ignition transformer?
2.
How
much voltage is supplied to the electrodes?
3.
Are
the electrodes permitted to enter into the oil spray?
4.
What
does enter into the oil spray to cause ignition?
5.
What
device is controlled by the operation of the triac?
6.
What
solid-state device controls the flow of gate current to the triac?
7.
Does
the CAD cell have a high resistance or low resistance when in the presence of
light?
8.
How
would the circuit operate if the CAD cell should be in the presence of light
when the thermostat called for heat?
$ Chapter 36

1.
What
is a legend?
2.
Refer
to figure 36-2. What would be the action of this circuit if the overload relay
should bum open?
3.
What
purpose does the thermistor connected in parallel with the capacitor serve?
4.
In
figure 36-2, what switch connections are made when the switch is in the HI position?
5.
In
figure 36-3, why is the thermostat switch shown as a single-pole double- throw?
6.

In figure 36-3, what do the
dashed lines showing connection between the start capacitor and start relay to
other parts of the circuit mean?
7.
In
figure 36-3, what color wire is connected between terminal 2 of the thermostat
and terminal C of the switch?
8.
What
color wire is connected between terminal 2 of the thermostat and the start
relay?
9.
In
figure 36-3, if no continuity is shown when one lead of an ohmmeter is
connected to switch terminal A and the other is connected to terminal C of the
compressor, what does it mean?
10. In figure 36-3, to what two points
should the terminals of an ohmmeter be connected to check the continuity of the
resistance heater circuit?
$ Chapter 37
1.
What
does the term CC mean if seen on a control schematic?
2.
What
does the term CPCS mean if seen on a schematic?
3.
Refer
to figure 37-2 for the following questions.
4.
If it
was desired to change the voltage controlling the short-cycle timer from 230
volts to 115 volts, what transformer leads should be connected together?
5.
Assume
the system has stopped operation. A voltmeter is connected across the LPS
switch terminals and it indicates 24 volts. The voltmeter is then connected
across the HPS switch and it indicates 0 volts. Which switch is stopping the
operation of the circuit?
6.
When
the system is operating normally, how much voltage should be seen across the CR
relay coil? '
$ Chapter 38
1.
What
is the purpose of terminal markings?
2.
What
two control components must be in a closed position before a heat pump is
permitted to go into the defrost cycle?
3.
The
thermostat shows a small pilot light connected between terminals Land C. What
condition of the thermostat turns this light on?
4.
What
is the purpose of the outdoor thermostat?
5.
What
is the operating voltage of the reversing valve solenoid?
$ Chapter 39
Refer to
the schematic shown in figure 39-1 for the following questions.
1.
The
unit will operate normally in the cooling cycle. When the unit is switched to
the heating cycle, the gas burner will not ignite. List four possible problems.
2.
The
blower fan will operate normally in the cooling cycle. In the heating cycle,
however, the fan will not operate. List three possible problems.
3.
The
unit will not operate in the heating or cooling cycle. A voltage check shows
that there is no low voltage for operation of the control circuit. List three
possible problems.
$ Chapter 40
1.
Ice
makers are divided into what two major categories?
2.
What
is the advantage of continually recirculating the water during the ice making
process?
3.
What
component controls the amount of water flow into the original compact ice
maker?
4.
Does
the flex tray ice maker require a mold heater to thaw the ice cubes before they
can be dumped into the storage bin?
5.
In
the original compact ice maker, what method is used to sense when the water has
been frozen?
6.
In
the original compact ice maker, what controls the start of the ejection and
refill cycle?
7.
In
the flex tray ice maker, what controls the start of the ejection and refill
cycle?
8.
How
can the original compact ice maker be manually turned off?
9.
How
many revolutions will the ejector blades of the original compact ice maker
normally make during the ejection cycle?
10. What is the function of the holding
switch in the original compact ice maker circuit?
11. Concerning the flex tray ice maker,
what two separate tasks are performed by the timer motor?
12. What is the function of the spring
loaded pin in the flex tray ice maker?
13. Concerning the flex tray ice maker,
is it possible for the timer motor to operate during the defrost cycle?
14. Concerning the new type compact ice
maker, what method is used to change the contacts labeled A, B, C, and D in the
schematic diagram shown in figure 40-18?
15. Can the gear of the new type
compact ice maker be rotated to manually advance the operation of the ice
maker?
16. How many revolutions do the ejector
blades of the new type compact ice maker make during the ejection cycle?
$ Chapter 41
1.
Concerning
the Scotsman cube-type ice maker, what device is used to cause the water to
flow evenly over the surface of the evaporator plate?
2.
Concerning
the Scotsman cube-type ice maker, what method is used to thaw the surface of
the ice in contact with the evaporator plate during the harvest cycle?
3.
Concerning
the Scotsman cube-type ice maker, what are the two safety switches used to
disconnect power from the control circuit?
4.
What
device is used to sense the level of ice cubes in the storage bin of the Scots-
man cube-type ice maker?
5.
What
electrical component starts the operation of the timer motor in the Scotsman
cube-type ice maker?
6.
Concerning
the Scotsman flaker-type ice maker, what device is used to carry the ice to the
top of the evaporator tube?
7.
How
is excess water pressed out of the ice before it is ejected into the storage
bin of the flaker-type ice maker?
8.
Explain
the operation of the auger delay switch used in the flaker-type ice maker.
9.
Concerning
the flaker-type ice maker, why is it desirable to have the auger drive motor
continue to operate for some period of time after the compressor has stopped
operation?
10. What controls the operation of the
bottom condenser fan motor in the flaker-type ice maker?
11. What electrical component is used
to stop the operation of the compressor if the auger should become overloaded?
12. Concerning the Scotsman flaker-type
ice maker, which safety switch must be manually reset if it trips?
$ Chapter 42
1.
How
many valence electrons are contained in a material used as a conductor?
2.
How
many valence electrons are contained in a material used as an insulator?
3.
What
are the two most common materials used to produce semi-conductor devices?
4.
What
is a lattice structure?
5.
How
is a P-type material made?
6.
How
is an N-type material made?
7.
What
type of semi-conductor material can withstand the greatest amourtt of heat?
8.
All
solid-state components are formed from combinations of P- and N-type materials.
What factors determine what kind of components will be formed?
$ Chapter 43
1.
What
is the PN junction more commonly known as?
2.
On a
plastic case diode, how are the leads identified?
3.
Explain
how a diode operates.
4.
Explain
the difference between the conventional current flow theory and the electron
flow theory.
5.
Explain
the difference between a half-wave rectifier and a full-wave rectifier.
6.
Explain
how to test a diode with an ohmmeter.
$ Chapter 44
1.
Will the LED rectify an AC voltage into a DC
voltage?
2.
What
is the average voltage drop of an LED?
3.
How
can the anode and cathode of an LED be identified?
4.
What
is the average amount of current permitted to flow through an LED?
5.
Can
LEDs be tested with most ohmmeters?
$ Chapter 45
1.
What
are the two basic types of transistors?
2.
Explain
how to test an NPN transistor with an ohmmeter.
3.
Explain
how to test a PNP transistor with an ohmmeter.
4.
What
polarity must be connected to the collector, base, and emitter of an NPN to
make it forward t:iased?
5.
What
polarity must be connected to the collector, base, and emitter of a PNP
transistor to make it forward biased?
6.
Explain
the difference between an analog device and a digital device.
$ Chapter 46
1.
What
do the letters UJT stand for?
2.
How
many layers of semi-conductor material are used to construct a UJT?
3.
Briefly
explain the operation of the UJT.
4.
Draw
the schematic symbol for the UJT.
5.
Briefly
explain how to test a UJT with an ohmmeter.
1.
What
do the letters SCR stand for?
2.
How
many layers of semi-conductor material are joined to form an SCR?
3.
SCRs
are a member of what family of devices?
4.
If an
SCR is connected in an AC circuit, is the output AC or DC?
5.
Is
gate current used to turn the SCR on or off?
6.
The
amount of current flow through the anode-cathode section needed to keep an SCR
turned on is called what?
7.
When
an SCR is connected in an AC circuit, what must be done to gain complete
control of the output waveform?
8.
What electronic component is generally used to phase shift
an SCR?
$ Chapter 48
1.
Briefly
explain how a diac operates.
2.
Draw
the two schematic symbols for the diac.
3.
What
is the major use of the diac in industry?
4.
When
a diac fIrst turns on, does the voltage drop, remain at the same level, or increase
to a higher level?
$ Chapter 49
1.
Draw
the schematic symbol of a triac.
2.
When
a triac is connected in an AC circuit, is the output AC or DC?
3.
The
triac is a member of what family of devices?
4.
Briefly
explain why a triac must be phase shifted.
5.
What
electronic component is frequently used to phase shift the triac?
6.
When
the triac is being tested with an ohmmeter, which other terminal should the
gate be connected to if the ohmmeter is to indicate continuity?
$ Chapter 50
1.
When
the voltage connected to the inverting input is more positive than the voltage
connected to the noninverting input, will the output be positive or negative?
2.
What
is the input impedance of a 741 operational amplifier?
3.
What
is the average open loop gain of the 741 operational amplifier?
4.
What
is the average output impedance of the 74l?
5.
List
the three common connections for operational amplifiers.
6.
When the
operational amplifier is connected as a voltage follower, it has a gain of one.
If the input voltage does not get amplified, what does?
7.
Name
two effects of negative feedback.
8.
Refer
to figure 50-8. If resistor Rl is 200 ohms, the resistor R2 is 10K ohms, what
is the gain of the amplifier?
9.
Refer
to figure 50-9. If resistor Rl is 470 ohms and resistor R2 is 47K ohms, what is
the gain of the amplifier?
10. What is the purpose of the
hysteresis loop when the op amp is used as an oscillator?