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STUDY GUIDE 2026
Current flow is the; flow of voltage in a circuit. flow of electrons in the circuit. impedance of a circuit. inductive reactance of the circuit. - correct answer ✅B Impedance is the measurement of the; ... amperage in a circuit. electrical pressure in a circuit. opposition to the flow of alternating current through a circuit. voltage applied to the circuit. - correct answer ✅C Like charges; ... are negative. are positive. attract one another. repel each other. - correct answer ✅D Any material that will readily release electrons is called a/an; ... conductor.
STUDY GUIDE 2026
insulator. neutron. resistor. - correct answer ✅A The symbol for current is; ... E. I. R. W. - correct answer ✅B Which of the following materials would be used as a semi- conductor? ... Aluminum Copper Mercury Silicon - correct answer ✅D The color of the safety ground wire is usually; ... black or white. green or bare. red or white.
STUDY GUIDE 2026
Cooling anticipation is performed by the thermostat; ... during the off cycle. during the on cycle. in minutes of compressor off time. minutes squared of compressor run time. - correct answer ✅A In electrical wiring, a black colored witre in an aemating curent crout usualy indicates the: ... ground conductor. hot conductor. neutral conductor. safety ground. - correct answer ✅B Fuses are sized by; ... amps & watts. volts & amps volts & watts. watts & ohms. - correct answer ✅B If a 24-volt, 20-ohm, low-voltage contactor coil were wired in series with a 24-volt, 200-hm control relay coil what would the result be?
STUDY GUIDE 2026
Both the contactor and control relay would operate. Neither the contactor nor control relay would operate. Only the control relay would operate. Only the contactor would operate - correct answer ✅C Three (3) defrost heaters, each 15 ohms, are wired in parallel to a 120-volt power supply. How many watts of power will be used? ... 8 watts. 24 watts 1800 watts. 2880 watts. - correct answer ✅D Which of the following is generally considered to be within the maximum allowable (+/-) supply voltage variation for a 230-volt supply? ... 184 to 242 volts 196 to 245 volts 207 to 276 volts 219 to 242 volts - correct answer ✅D Capacitors are rated in; ...
STUDY GUIDE 2026
746 watts. 1,200 watts. - correct answer ✅C How much resistance must be placed in a 120-volt circuit to limit the current to 2 amps? ... 60 ohms. 118 ohms 120 ohms 240 ohms - correct answer ✅A A parallel circuit contains an 18-ohm and 9-ohm resistor. The total resistance equals; ... 6 ohms 8 ohms. 10 ohms 27 ohms. - correct answer ✅A In a series circuit, the voltage drop acros each resistance (a) will; ... add up to equal the source voltage. add up to the total resistance. depend on the current to each resistor.
STUDY GUIDE 2026
depend on the wire gauge. - correct answer ✅A The total resistance of a parallel circuit will be; ... equal to the largest resistance equal to the smallest resistance. less than the smallest resistance. the sum of all resistances. - correct answer ✅D Current flow will increase when; ... current flow is the same as voltage. resistance increases. voltage decreases. voltage increases. - correct answer ✅D When resistors are wired in parallel the; ... current through any one resistor will be the same as the total circuit current. total resistance is determined by adding the values of each resistor. voltage drop across each resistor will be the same as the applied source voltage.
STUDY GUIDE 2026
Which device changes the pressure signal in an electronic oil safety switch to an electrical signal? ... Electronic processor The bellows The circuit board Transducer - correct answer ✅D Heatng anticipation is performed by a mechanical thermostat; ... by the off time of the fumace, in minutes. by the run time of the fumace, in minutes. during the off cycle. during the on cycle. - correct answer ✅C A three-phase load requires a minimum of; ... three supply lines three supply lines and a neutral. two supply lines. two supply lines and a ground. - correct answer ✅A The correct formula for determining wattage in an electrical circuit is;
STUDY GUIDE 2026
W= Ex | W=E/R W=Ex R W=I/R - correct answer ✅A A parallel circuit consists of three resistors [R1 = 30 ohms R2 = 15 ohms R3 = 10 ohms] if the current through 52 - amares, hat is the source voltage? ... 20 volts 60 volts 120 volts 220 volts - correct answer ✅B Thre (3) resistors, each 300 ohms, are wired in parall. The total resistance equals; ... 100 ohms 300 ohms. 600 ohms. 900 ohms. - correct answer ✅A An electronically commutated motor (ECM) used in an air-handler is designed to;
STUDY GUIDE 2026
charged capacitor until it has been discharged coil or a winding of a compressor. motor that has a grounded condition. resistor until it has been checked by other means. - correct answer ✅A Which of the following would be considered an inductive load? ... electric heat strip electric motor solid state relay start capacitor - correct answer ✅B The voltage to ground of a "High leg" on a three-phase open Delta system will be approximately ... 120 208 220 240 - correct answer ✅B A transformer has 1,000 turns of wire in the primary coil and 500 turns in the secondary coil. If 120-volts are applied, the output voltage will be; ...
STUDY GUIDE 2026
60 volts. 120 KV 240 volts. 620 volts. - correct answer ✅A A transformer has 1,000 turns of wire in the primary coil and 2000 turns in the secondary coil. If 120-volts are applied, the output voltage will be; ... 60 volts. 120 KV 240 volts. 620 volts. - correct answer ✅C Which of the following letter is the representation for impedance in an AC circuit? ... W X Y Z - correct answer ✅D When current lows in a two-wire circuit (such as 120 volts) if a camp on amp meter is clamped around both wires what measurement would you expect?
STUDY GUIDE 2026
A diode and a DC capacitor are wired in series with the fan circuit and the common terminal. A diode and an AC capacitor are wired in series with either the heating or cooling circuit and the common terminal. The common is made through the "C" terminal on the system compressor. An add-a-wire accessory can be used to take the place of terminals "y" and "G" - correct answer ✅D The direction of rotation of a single-phase induction motor is determined by the; ... direction of current flow through the run winding. direction of current flow through the start winding. number of poles in the motor. voltage applied to the start winding. - correct answer ✅B Single-phase motor speed is determined by the; ... circumference of the rotor. number of coils in the stator. number of stator poles. supply voltage. - correct answer ✅C
STUDY GUIDE 2026
The capacitor start-capacitor run (SCR) motor provides; ... high running and low starting torque. high running and medium starting torque. high starting and high running torque. medium running and high starting torque. - correct answer ✅D To change direction of rotation of a three-phase motor; ... change the position of all three supply wires. change the position of any two supply wires. the motor must be replaced. the rotation of three phase motors cannot be changed. - correct answer ✅B Capacitors are always connected to the start winding; ... in parallel. in series. through a diode. through a relay. - correct answer ✅B Which function of a digital multimeter is used to bench check a motor for shorts or open windings?
STUDY GUIDE 2026
common to run terminals will show the lowest resistance. common to start terminals will show the lowest resistance. pair of terminals with the highest resistance will indicate that the other terminal is the start. start to run terminals will show the lowest resistance. - correct answer ✅A A direct digital control (DDC) is a/an; ... digital control for controlling the electron flow in a series circuit. digital control for controlling the electron flow in a parallel circuit. electronic control that must be manually adiusted. electronic control used for equipment operation and monitoring. - correct answer ✅D A step-up transformer increases; ... amperage. power. resistance. voltage - correct answer ✅D Transformers are rated according to; ... ohms at the primary.
STUDY GUIDE 2026
ohms at the secondary. volt-amps (VA) at the primary: volt-amps (VA) at the secondary. - correct answer ✅D How many diodes are used to make a bridge rectifier connected to a 2-wire transformer? ... 1 2 3 4 - correct answer ✅D What connects to teminals 1, T2, & T3 on a contactor or motorstater? ... Coil connections and ground Load connections. Power supply connections Start / stop leads - correct answer ✅B Circuit breakers and fuses are primarily used for; ... protection from an overload of current. protection of over impedance to a condensing unit. C
