ABYC MARINE ELECTRICAL FINAL EXAM
ACTUAL QUESTIONS AND ANSWERS SURE
A+
✔✔B. Tech B - ✔✔The A says the a faulty circuit breaker could require an overhaul.
Tech B says that circuit breakers used in recreational marine applications must be
replaced if found defective. Who's right?
A. Tech A
B. Tech B
C. Both may be correct, depending on circumstances
D. Neither
✔✔B. 3% - ✔✔The maximum allowable voltage drop permitted for panel board DC
feeders is:
A. 2%
B. 3%
C. 10%
D. 15%
✔✔True - ✔✔T or F: Solid (non-stranded) conductors are not allowed for AC wiring
anywhere on a boat.
✔✔False. Auto-reset is not allowed. - ✔✔T or F: magnetic transformers with integrated
secondary-side overcurrent protection and automatically resetting thermal overload
protection are ABYC compliant.
✔✔C. Continuity - ✔✔To test a 120V AC element in a hot water heater, the tech may
run a _____ test.
A. Voltage
B. Capacitance
C. Continuity
D. Inductance
,✔✔B. Inside an enclosure requiring the use of hand-tools to open - ✔✔All terminations
and junctions for AC conductors must be installed:
A. in free air to allow for proper ventilation
B. Inside an enclosure requiring the use of hand-tools to open
C. In conduit
D. In snap-covered junction boxes
✔✔D. TDR - ✔✔Wha is the best tool to use for locating short-circuits?
A. Megger
B. Amp Clamp
C. DVM
D. TDR
✔✔A. Cooler - ✔✔High frequency transformers typically run _____ than traditional
magnetic transformers.
A. Cooler
B. Hotter
C. Faster
D. Slower
✔✔6 lbs for 1 minute (E-11.13.2.3) - ✔✔What is the pull-test requirement for DC
plug/receptacles?
✔✔True - ✔✔T or F: For AC wiring, the "hot" ungrounded conductor (i.e., not the
insulation color) should be brass or copper colored and the "neutral" grounded
conductor should be light silver colored.
✔✔600 Watts for 15-amp circuit, 1000 Watts for 20-amp circuit (E-11.13.3.4) - ✔✔For a
branch circuit supplying both receptacle loads and permanently connected loads, what
is the maximum recommended permanent load for 15-amp circuit? For 20-amp circuit?
✔✔2 Watts / sq. ft. (E-11.8.2.2.1.1) - ✔✔When calculating AC loads, what is the
recommended wattage per square foot of living area?
✔✔1500 Watts / 20 A circuit (E-11.8.2.2.1.2) - ✔✔When calculating AC loads for small
galley appliances, how many watts should be used for each 20 amp circuit?
✔✔True - ✔✔T or F: when installing a remote solenoid for switching high-current draws
like windlass, bow-thruster, etc, a separate appropriately sized overcurrent protection
must be in place for both the low-current and high-current wiring of the solenoid.
✔✔As the motor heats up, winding resistance increases causing a corresponding
decrease in current draw. Fire hazard. Thermal protection device recommended in
motors! - ✔✔Describe the reason why a locked-rotor motor may not trip an overcurrent
protection device.
,✔✔seven hours (E-11.10.1.3.1) - ✔✔For how long must a motor be able to sustain a
locked rotor condition without inducing a fire hazard?
✔✔True - ✔✔T or F: if no standard rating OC protection device is available which
equals 100% of the allowable current for the conductor being protected, the next larger
rating, up to 150% of the conductor ampacity, may bee used - unless the load is a
motor.
✔✔On diesels, the oil pressure sender may be used to switch alternator on/off and the
trigger the tachometer. - ✔✔Describe why a non-functional tachometer and charging
system on a diesel engine may be caused by a failed oil pressure sending unit.
✔✔False - ✔✔True or False: AC receptacles may be used for DC service, provided they
are properly labeled.
✔✔B. Tech B - ✔✔Tech A says that combined AC/DC panel boards are grounded via
the DC negative bus. Tech B says that such panel boards should be grounded to the
AC grounding bus. Which tech is right?
A. Tech A
B. Tech B
C. Both techs are correct
D. Neither tech is correct
✔✔Closed when in neutral (therefore, an open-circuit failure would prevent engine
starting) - ✔✔Start-in-gear protection switches should be open or closed when in
neutral?
✔✔Styrene from curing fiberglass, methane from head/holding tank, hydrogen from
battery outgassing or refrigeration leaks - ✔✔Name three common gasses other than
CO that may trigger a CO alarm:
✔✔Excessive humidity, low supply voltage - ✔✔Name two likely possible causes of
falsely trigger fire alarm in an engine room space.
✔✔True - ✔✔T or F: boats with an enclosed accommodation compartment shall have
an audible high bilge-water alarm.
✔✔4 AWG - ✔✔What gauge wire is required at a minimum for the primary down
conductor from a lightning Air Terminal?
✔✔1 sq. ft. - ✔✔What is the minimal required surface area for lightning protection
system's immersed ground plate?
, ✔✔6 AWG - ✔✔What gauge wires is required for lightning protection system secondary
conductors?
✔✔30 mA, 100 ms - ✔✔What is the maximum allowable trip current & time for
ELCI/RCD at the main shore power input?
✔✔False - ✔✔T or F: CO detectors will also detect smoke in most situations.
✔✔Peak Voltage = 1.414 * RMS Voltage
or, V peak * .707 = V RMS - ✔✔For true RMS inverters what is the relationship between
peak and RMS voltage?
✔✔2-3% - ✔✔What is the max typically allowable % difference between true sinusoidal
peak AC voltage and harmonically distorted peak AC voltage?
✔✔shorter, thicker terminal is HOT
taller, narrower terminal is NEUTRAL - ✔✔On a standard 3-conductor AC outlet, which
of the two blade conductors (i.e., not the rounded GROUNDING conductor) is Hot and
which is Neutral?
✔✔A. An open circuit in the neutral to ground link at an AC generator - ✔✔A polarity
indicator light that is glowing more dimly than normal could be an indicator of:
A. An open circuit in the neutral to ground link at an AC generator
B. An open circuit in the hot wire connection
C. A ground connection with very low impedance
D. Excessive AC frequency
✔✔D. A neutral-to-gound link at the boats AC panel board - ✔✔When using a high-
resolution amp clamp on a shore power cord and activating AC circuits one by one, the
technician notes that the AC leakage current measured increases with each appliance.
This most likely indicates:
A. An open-circuit in the grounding conductor on the dock
B. Excessively high voltage delivered by the utility company
C. Excessive voltage drops in the AC power supply to the boat
D. A neutral-to-gound link at the boats AC panel board
✔✔E. All of the above - ✔✔A system voltmeter shall be installed on the main panel
board if the system is permanently connected to:
A. Inverter
B. Generator
C. Motor
D. B & C above
E. All of the above
ACTUAL QUESTIONS AND ANSWERS SURE
A+
✔✔B. Tech B - ✔✔The A says the a faulty circuit breaker could require an overhaul.
Tech B says that circuit breakers used in recreational marine applications must be
replaced if found defective. Who's right?
A. Tech A
B. Tech B
C. Both may be correct, depending on circumstances
D. Neither
✔✔B. 3% - ✔✔The maximum allowable voltage drop permitted for panel board DC
feeders is:
A. 2%
B. 3%
C. 10%
D. 15%
✔✔True - ✔✔T or F: Solid (non-stranded) conductors are not allowed for AC wiring
anywhere on a boat.
✔✔False. Auto-reset is not allowed. - ✔✔T or F: magnetic transformers with integrated
secondary-side overcurrent protection and automatically resetting thermal overload
protection are ABYC compliant.
✔✔C. Continuity - ✔✔To test a 120V AC element in a hot water heater, the tech may
run a _____ test.
A. Voltage
B. Capacitance
C. Continuity
D. Inductance
,✔✔B. Inside an enclosure requiring the use of hand-tools to open - ✔✔All terminations
and junctions for AC conductors must be installed:
A. in free air to allow for proper ventilation
B. Inside an enclosure requiring the use of hand-tools to open
C. In conduit
D. In snap-covered junction boxes
✔✔D. TDR - ✔✔Wha is the best tool to use for locating short-circuits?
A. Megger
B. Amp Clamp
C. DVM
D. TDR
✔✔A. Cooler - ✔✔High frequency transformers typically run _____ than traditional
magnetic transformers.
A. Cooler
B. Hotter
C. Faster
D. Slower
✔✔6 lbs for 1 minute (E-11.13.2.3) - ✔✔What is the pull-test requirement for DC
plug/receptacles?
✔✔True - ✔✔T or F: For AC wiring, the "hot" ungrounded conductor (i.e., not the
insulation color) should be brass or copper colored and the "neutral" grounded
conductor should be light silver colored.
✔✔600 Watts for 15-amp circuit, 1000 Watts for 20-amp circuit (E-11.13.3.4) - ✔✔For a
branch circuit supplying both receptacle loads and permanently connected loads, what
is the maximum recommended permanent load for 15-amp circuit? For 20-amp circuit?
✔✔2 Watts / sq. ft. (E-11.8.2.2.1.1) - ✔✔When calculating AC loads, what is the
recommended wattage per square foot of living area?
✔✔1500 Watts / 20 A circuit (E-11.8.2.2.1.2) - ✔✔When calculating AC loads for small
galley appliances, how many watts should be used for each 20 amp circuit?
✔✔True - ✔✔T or F: when installing a remote solenoid for switching high-current draws
like windlass, bow-thruster, etc, a separate appropriately sized overcurrent protection
must be in place for both the low-current and high-current wiring of the solenoid.
✔✔As the motor heats up, winding resistance increases causing a corresponding
decrease in current draw. Fire hazard. Thermal protection device recommended in
motors! - ✔✔Describe the reason why a locked-rotor motor may not trip an overcurrent
protection device.
,✔✔seven hours (E-11.10.1.3.1) - ✔✔For how long must a motor be able to sustain a
locked rotor condition without inducing a fire hazard?
✔✔True - ✔✔T or F: if no standard rating OC protection device is available which
equals 100% of the allowable current for the conductor being protected, the next larger
rating, up to 150% of the conductor ampacity, may bee used - unless the load is a
motor.
✔✔On diesels, the oil pressure sender may be used to switch alternator on/off and the
trigger the tachometer. - ✔✔Describe why a non-functional tachometer and charging
system on a diesel engine may be caused by a failed oil pressure sending unit.
✔✔False - ✔✔True or False: AC receptacles may be used for DC service, provided they
are properly labeled.
✔✔B. Tech B - ✔✔Tech A says that combined AC/DC panel boards are grounded via
the DC negative bus. Tech B says that such panel boards should be grounded to the
AC grounding bus. Which tech is right?
A. Tech A
B. Tech B
C. Both techs are correct
D. Neither tech is correct
✔✔Closed when in neutral (therefore, an open-circuit failure would prevent engine
starting) - ✔✔Start-in-gear protection switches should be open or closed when in
neutral?
✔✔Styrene from curing fiberglass, methane from head/holding tank, hydrogen from
battery outgassing or refrigeration leaks - ✔✔Name three common gasses other than
CO that may trigger a CO alarm:
✔✔Excessive humidity, low supply voltage - ✔✔Name two likely possible causes of
falsely trigger fire alarm in an engine room space.
✔✔True - ✔✔T or F: boats with an enclosed accommodation compartment shall have
an audible high bilge-water alarm.
✔✔4 AWG - ✔✔What gauge wire is required at a minimum for the primary down
conductor from a lightning Air Terminal?
✔✔1 sq. ft. - ✔✔What is the minimal required surface area for lightning protection
system's immersed ground plate?
, ✔✔6 AWG - ✔✔What gauge wires is required for lightning protection system secondary
conductors?
✔✔30 mA, 100 ms - ✔✔What is the maximum allowable trip current & time for
ELCI/RCD at the main shore power input?
✔✔False - ✔✔T or F: CO detectors will also detect smoke in most situations.
✔✔Peak Voltage = 1.414 * RMS Voltage
or, V peak * .707 = V RMS - ✔✔For true RMS inverters what is the relationship between
peak and RMS voltage?
✔✔2-3% - ✔✔What is the max typically allowable % difference between true sinusoidal
peak AC voltage and harmonically distorted peak AC voltage?
✔✔shorter, thicker terminal is HOT
taller, narrower terminal is NEUTRAL - ✔✔On a standard 3-conductor AC outlet, which
of the two blade conductors (i.e., not the rounded GROUNDING conductor) is Hot and
which is Neutral?
✔✔A. An open circuit in the neutral to ground link at an AC generator - ✔✔A polarity
indicator light that is glowing more dimly than normal could be an indicator of:
A. An open circuit in the neutral to ground link at an AC generator
B. An open circuit in the hot wire connection
C. A ground connection with very low impedance
D. Excessive AC frequency
✔✔D. A neutral-to-gound link at the boats AC panel board - ✔✔When using a high-
resolution amp clamp on a shore power cord and activating AC circuits one by one, the
technician notes that the AC leakage current measured increases with each appliance.
This most likely indicates:
A. An open-circuit in the grounding conductor on the dock
B. Excessively high voltage delivered by the utility company
C. Excessive voltage drops in the AC power supply to the boat
D. A neutral-to-gound link at the boats AC panel board
✔✔E. All of the above - ✔✔A system voltmeter shall be installed on the main panel
board if the system is permanently connected to:
A. Inverter
B. Generator
C. Motor
D. B & C above
E. All of the above
