Electrical Terms and Definitions – Self Test 1

Questions

1. Unless specifically marked, the total connected electrical load shall not exceed _____ of the rating of the circuit’s overcurrent device.
   1. 75%
   2. 80%
   3. 100%
   4. 125%
2. Household heating and cooling equipment is supplied by which style of voltage?
   1. Single-phase
   2. Three-phase
   3. Double-phase
   4. Opposing-phase
3. An overload is a:
   1. Sharp fast rise in current values above rated levels.
   2. A slow, prolonged rise in current values above rated levels.
   3. A decrease in current values below rated levels.
   4. An immediate drop in current values to zero.
4. An overcurrent is a:
   1. Sharp fast rise in current values far above rated levels.
   2. A slow rise in current values above rated levels.
   3. A decrease in current values below rated levels.
   4. An immediate drop in current values to zero.
5. Low-voltage-release is a term that describes a:
   1. Circuit that will automatically reenergize after return of power following a power outage.
   2. Circuit that will not automatically reenergize after return of power following a power outage.
   3. Circuit that will remain energized despite a power outage.
   4. Circuit that will automatically open the contacts of an overcurrent device upon loss of power.
6. Low-voltage-protection is a term that describes a:
   1. Circuit that will automatically reenergize after return of power following a power outage.
   2. Circuit that will not automatically reenergize after return of power following a power outage.
   3. Circuit that will remain energized despite a power outage.
   4. Circuit that will automatically open the contacts of an overcurrent device upon loss of power.
7. Low-voltage-release is provided by circuits known as:
   1. 2-wire circuits
   2. 3-wire circuits
   3. 4-wire circuits
   4. Single-wire circuits
8. Low-voltage-protection is provided by circuits known as:
   1. 2-wire circuits
   2. 3-wire circuits
   3. 4-wire circuits
   4. Single-wire circuits

Answers

1. B
2. A
3. B
4. A
5. A
6. B
7. A
8. B

Heating – Self Test 2

Questions

1. When an electric heating load is inadvertently connected at half its rated voltage, the power dissipated is:
   1. Four times the rated power
   2. Twice the rated power
   3. One quarter the rated power
2. When an electric heating load is inadvertently connected at twice its rated voltage, the power dissipated is
   1. Four times the rated power
   2. Twice the rated power
   3. Half the rated power
   4. One quarter the rated power
3. Is it acceptable to install electrical receptacles directly above baseboard heaters?
   1. Yes, always.
   2. No, never.
   3. Occasionally, as long as they look nice.
   4. Yes, only with GFCI protection.
4. When a fireplace uses a self-generating 750 millivolt system, what device is used to supply the power for the gas valve?
   1. A thermopile
   2. A thermocouple
   3. A solenoid
   4. A bimetallic switch
5. What is the purpose of the heat exchanger in a gas-fired furnace?
   1. To separate the heated air from the cold air return
   2. To separate heated air from the air flow to the rooms
   3. To separate the products of combustion from the gas valve
   4. To separate the products of combustion from the heated air
6. Where must the automatic thermostatic control be when baseboard heaters are used to heat a dwelling unit?
   1. on each branch circuit
   2. on each individual unit
   3. in each overcurrent device
   4. in each room or heated area
7. A thermocouple is generally thought of as:
   1. A voltage device
   2. An impedance device
   3. A current device
   4. A resistance device
8. In floor heating cables are designed to provide enough heat to do what?
   1. Heat the room or area
   2. Reduce the heating demand of baseboard heaters
   3. Reduce the heating demand of the furnace
   4. Eliminate cold floors
9. Some heating equipment will have a high-temperature-limit switch. What is the purpose of this switch?
   1. To protect against low temperature level
   2. To set the temperature of the water
   3. To prevent temperature from exceeding a safe value
   4. To regulate gas flow
10. When a stronger signal than a thermocouple is required, a thermopile can be used. How are thermocouples connected to make a thermopile?
    1. In series-aiding
    2. 3-wire
    3. In series-opposing
    4. In parallel
11. Why is a thermocouple used in conjunction with a pilot light in a gas fired furnace?
    1. To ensure immediate ignition of gas with the opening of the main gas valve
    2. To re-ignite the pilot flam should it be extinguished
    3. To hold open the pilot-flame valve while it is lit, and automatically close it if the pilot-flame is extinguished
    4. To prevent the pilot-flame valve from closing if the flam is extinguished
12. A thermostat is considered a:
    1. Temperature activated switch
    2. Liquid-level switch
    3. Position sensing switch
    4. Pressure switch
13. A programable thermostat combines the features of which two devices?
    1. An electronic timer and a thermostat
    2. A thermostat and an anticipator resistor
    3. An electronic timer and a load
    4. An electronic timer and an anticipator resistor
14. A low-voltage thermostat used to control a central gas fired furnace will incorporate an _____________ to prevent overshoot of desired room temperature.
    1. Anticipator resistor
    2. Normally open contact
    3. Normally closed contact
    4. An electronic timer
15. A 240-volt line-voltage thermostat used to control the household heating apparatus, when in the marked “off” position, it must disconnect?
    1. The grounded conductor only
    2. Two ungrounded conductors
    3. One ungrounded conductor
    4. The grounding conductor only
16. A 240-volt line-voltage thermostat used to control the household heating apparatus, when in the marked “min” position, it must disconnect?
    1. The grounded conductor only
    2. Two ungrounded conductors
    3. One ungrounded conductor
    4. The grounding conductor only
17. If extra low voltage relays and thermostats are used to control heating equipment, which one of the following is not a valid reason for their use?
    1. Reduce voltage ratings of control conductors
    2. To reduce the equipment cost
    3. To decrease the control circuit current draw
    4. To increase the heating capacity
18. If a baseboard thermostat has a rating of 20 amps at 250 volts, what is the maximum wattage heating unit that it can control?
    1. 2,500 W
    2. 1,000 W
    3. 1,500 W
    4. 5,000 W

Answers

1. C
2. A
3. B
4. A
5. D
7. A
8. D
9. C
10. A
11. C
12. A
13. A
14. A
15. B
16. C
17. D
18. D

Ventilation – Self Test 3

Questions

1. In order to maintain healthy air levels in a building, a certain amount of ___________ is mixed in with the treated air.
   1. Fresh air
   2. Carbon-dioxide
   3. Products of combustion
   4. Reverse air flow
2. The term “static pressure” when applied to ventilation refers to:
   1. Maximum pressure the air-handling unit can handle
   2. The force exerted by a moving air stream
   3. The outward force of the air in the ducting system
   4. The resistance to the flow of air in a ducting system
3. The term “velocity pressure” when applied to ventilation refers to:
   1. Maximum pressure the air-handling unit can handle
   2. The force exerted by a moving air stream
   3. The outward force of the air in the ducting system
   4. The resistance to the flow of air in a ducting system
4. The term “total pressure” when applied to ventilation refers to:
   1. Maximum pressure the air-handling unit can handle
   2. The force exerted by a moving air stream
   3. The outward force of the air in the ducting system
   4. The resistance to the flow of air in a ducting system
5. Axial fans have outgoing air flow that is _____________ to the air intake
   1. Parallel
   2. Perpendicular
   3. Inverted
   4. Oblique
6. Centrifugal fans have outgoing air flow that is _____________ to the air intake.
   1. Parallel
   2. Perpendicular
   3. Inverted
   4. Oblique
7. Axial fans are often employed to:
   1. Move air through an HVAC system
   2. Move air over the condenser coils of air-conditioning systems
   3. Prevent air from moving in a certain direction
   4. Recirculate air in a room
8. Centrifugal fans are often employed to:
   1. Move air through an HVAC system
   2. Move air over the condenser coils of air-conditioning systems
   3. Recirculate air in a room
   4. Prevent air from moving in a certain direction
9. Dampers are devices installed in the duct work of buildings to
   1. Help regulate the flow of air through a duct system
   2. Drive air from heated to non-heated areas
   3. Prevent the mixing of fresh air from outside the building
   4. Monitor the flow of air through a duct system

Answers

1. A
2. C
3. B
4. D
5. A
6. B
7. B
8. A
9. A

Mechanical Cooling – Self Test 4

Questions

1. A heat pump can also be used to cool the building when the outside air temperature is warm. How is this achieved?
   1. The direction of flow of the air is reversed
   2. The direction of flow of the refrigerant is reversed
   3. The direction of flow of the current is reversed
   4. The direction of rotation of the motor is reversed
2. When using DX cooling, which device is responsible for capturing heat from whatever place or medium needs to be cooled?
   1. Condenser
   2. Refrigerant
   3. Evaporator
   4. Compressor
3. When using DX cooling, which device is responsible for releasing heat from whatever place or medium needs to be cooled?
   1. Condenser
   2. Refrigerant
   3. Evaporator
   4. Compressor
4. When using DX cooling, what is responsible for transferring thermal energy from whatever place or medium needs to be cooled?
   1. Condenser
   2. Refrigerant
   3. Evaporator
   4. Compressor
5. When using DX cooling, which device is responsible for driving the refrigerant from whatever place or medium needs to be cooled?
   1. Condenser
   2. Refrigerant
   3. Evaporator
   4. Compressor
6. What process does mechanical refrigeration rely on to work?
   1. Evaporation
   2. Conduction
   3. Convection
   4. Radiation
7. What name is given to the method of removing energy in the form of heat from an object?
   1. Conduction
   2. Convection
   3. Refrigeration
   4. Radiation
8. What do air-cooled condensers use to circulate air across the condensing coil?
   1. Exhaust system
   2. Ambient evaporation
   3. A chiller pump
   4. A motor-driven fan
9. What is used by a hydronic system that allows it to be used for both the heating and cooling of a home?
   1. A draft regulator
   2. Hydraulic fluid
   3. Pneumatic air
   4. Fluid, such as water
10. Thermal energy is _____________ by a DX cooling system
    1. Created
    2. Destroyed
    3. Transferred
    4. Eliminated
11. Thermal energy flows spontaneously from areas of ____________ to areas of _____________.
    1. Higher temperature, lower temperature
    2. Lower temperature, higher temperature
    3. Ambient temperature, lower temperature
    4. Higher temperature, ambient temperature
12. An exothermic reaction ______________ thermal energy from the surrounding environment
    1. Releases
    2. Absorbs
    3. Creates
    4. Destroys
13. An endothermic reaction ______________ thermal energy from the surrounding environment.
    1. Releases
    2. Absorbs
    3. Creates
    4. Destroys

Answers

1. B
2. C
3. A
4. B
5. D
6. A
7. C
8. D
9. D
10. C
11. A
12. A
13. B