ABYC Marine Electrical Questions And Answers 2024 Update A+

___ through circuits on a boat is perhaps the most common problem with electrical circuitry. A Overly high rates of current flow B Resistance to heat C Unrestricted pressure D Resistance to electrical current flow - Answer-D Resistance to electrical current flow When using Ohm's law, if any two of the three values are known, the third value can be calculated by ___. A multiplication or division B addition or subtraction C taking the square root of the sum of the two values D finding the inverse of the highest known value - Answer-A multiplication or division If the voltage in a circuit is 12 volts and the resistance is 3 ohms, Ohm's law can be used to find that the rate of flow is ___ amps. A 9 B 6 C 4 D 2 - Answer-C. 4 If resistance decreases and the voltage remains constant in a circuit, then the amperage will ___. A decrease B increase C remain constant D be canceled out - Answer-B increase The unit of measure for power is the ___. A watt B ampC volt D ohm - Answer-A watt A microwave oven with a wattage of 1.2 KW (1,200 watts) and a 120 VAC will draw ___ amps. A 100 B 60 C 20 D 10 - Answer-D 10 Cranking motor (engine starter) circuits are not required to have ___. - Answer-overcurrent protection In a ___ circuit, there is only one path allowed for electrical flow. A parallel B simple C series D starter - Answer-C series In a series circuit, the amperage (current) is ___. A the same everywhere it is measured B gradually decreased as the circuit runs farther from the power source C lowest at (or very close to) the power source D gradually increased as the circuit runs farther from the power source - Answer-the same everywhere it is measured In all circuits, voltage is lost as it travels through the circuit, which is commonly referred to as ___. A electrical resistance B voltage drop C short circuiting D open circuiting - Answer-B voltage drop The most common type of circuit fault is a(n) ___.A burnt-out circuit B intercircuit short C open circuit D internal short - Answer-C open circuit (Really should be Unwanted Open) The ___ is the most dangerous type of short circuit. A open circuit B internal short C intercircuit short D short circuit to ground - Answer-D short circuit to ground Intercircuit shorts are usually caused by ___. A inadequate ventilation in the area where the circuit is installed B water migration into a device C an errant screw sticking through a loom or wiring harness D insulation breakdown of the circuit components - Answer-C an errant screw sticking through a loom or wiring harness One horsepower is equal to ___ watts. - Answer-746 watts The primary by-product of excessive electrical resistance is ___. - Answer-Heat The Minimum amp circuit breaker that should be used to protect a 120V water heater circuit with at 1600 watt element should be rated at ___ Amps A. 15 B. 10 C. 20 D. 30 - Answer-A. 15 When testing for excessive EMF emission near a conductor or appliance, the tool of choice is a(n): A. ohmmeter B. DVOMC. Gauss Meter D. Infrared Sensor - Answer-C. Gauss Meter From the ABYC electrical diagram symbols, what symbol that illustrates a variable resistor: - AnswerThe Resistor Symbol of Up and Down Squigly with and Arrow: -vVVvThe primary problem with using a series circuit to supply multiple loads is that: A. Voltage drop through the circuit will be excessive B. The capacitance will be excessive C. Amperage draw will be multiplies D. the overcurrent protection device may not work - Answer-A. Voltage drop through the circuit will be excessive Based on Section 2, the most common electrical circuit problem is: - Answer-Unwanted Open Excessive Electrical resistance can be caused by_______ A. Oversized Conductors, loose terminals, and corrosion B. Improper wire insulation and excessive wire strand count C. fuses with too high of a rating and wattage that is too low D. undersized wire, loose connections, and corrosion - Answer-D. undersized wire, loose connections, and corrosion While there's some variation among countries, in North America the preferred colors for 120-volt AC are ___. A. red, blue, and black B. white, light blue, and brown C. black, white, and green D. red, orange, and blue - Answer-C. black, white, and green If conductor color coding is not enough, alternative labeling may be used for DC conductors as long as a ___ is provided in the boat's documentation. A. line diagram B. general note or sheet noteC. clear photograph of the newly installed labeling D. wiring diagram or wiring legend - Answer-D. wiring diagram or wiring legend When AC and DC conductors converge at the back of panelboards, the use of ___ insulation for DC negative conductors gives a quick and distinctive differentiation between DC negative and AC hot conductors. - Answer-Yellow The insulation on grounding conductors should be either ___. A white or yellow B blue or light blue C green or green with a yellow stripe D black or black with a red stripe - Answer-C green or green with a yellow stripe A time-domain reflectometer (TDR) can confirm continuity and ___. A pinpoint the location of a short or open circuit B decrease the electrical conductivity of a material C display the amount of resistance present in a circuit D repair any short circuits that may be present - Answer-A pinpoint the location of a short or open circuit Most wiring-related problems occur ___. A. at the power source B. at termination points C. in short runs D. in long runs - Answer-B. at termination points For battery cable gauge sizes, the tool of choice for terminations is referred to as a ___, which leaves a square crimp on the terminal. A. battery connector B. signal generatorC. box cutter D. box crimper - Answer-D. box crimp