ABYC Marine Electrical Certification Exam Review 2026/2027
version with verified answers
Cranking- correct answer >>>Which type of battery generally recharges faster? Deep
cycle or cranking?
Wire brush and backing soda.- correct answer >>>What tool and common household
staple are used to clean battery terminals?
Most of the sulfuric acid has been absorbed into the lead plates, leaving mostly water in
the electrolyte.- correct answer >>>Why might a fully-discharged wet-cell type battery
freeze?
1 inch, 90 lbs or 2x the battery weight, for 1 minute in each direction.- correct answer
>>>Batteries must be secured to prevent movement of more than ______ inches in any
direction when a pulling force of _____ or _____, whichever is less, is applied through
the center of gravity of the battery for how long?
True- correct answer >>>T or F: it is ok to install batteries directly below an
uninterrupted fuel line?
Must be protected with dielectric insulating material- correct answer >>>What provision
must be in place on any fuel line located within 12 inches of a battery terminals?
80 F, 25 Amps, 10.5 Volts- correct answer >>>Define: Battery reserve capacity = the
number of minutes that a new, fully charged battery at ______ degrees F can be
continuously discharged at ______ amps while maintaining _____ volts (for a 12 v
battery)
90 minutes- correct answer >>>According to ABYC, what is the minimum battery
reserve capacity?
32 degrees F, 30 seconds, 7.2V- correct answer >>>Define: Marine Cranking Amps =
the discharge load, in amperes, that a new, fully-charged battery at _____ degrees F
can deliver for ______ seconds while maintaining a voltage of _____ volts (for a 12 v
battery).
0 degrees F, 30 seconds, 7.2V- correct answer >>>Define: Cold Cranking Amps = the
discharge load, in amperes, that a new, fully-charged battery at _____ degrees F can
deliver for ______ seconds while maintaining a voltage of _____ volts (for a 12 v
battery).
8 AWG- correct answer >>>What is the largest guage wire that may be connected to a
bettery with wing-nuts?
,800 CCA or 100 Ahr (exceptions: electronic equipment with battery backed memories;
safety equipment such as bilge pumps, alarms, CO detectors, bilge blowers; battery
chargers; I'm pressed current systems.- correct answer >>>Per ABYC E-10, a battery
switch must be installed in the positive conductor from each battery bank with a CCA
rating greater than ____ (or greater than _____ Ah if CCA rating not available).
AIC = 5000 Amps (E-11 table IV-A)- correct answer >>>What is the minimum ampere
interrupting capacity (AIC) for main overcurrent protection on a battery bank rated at 12
V, 1500 CCA?
AIC = 2X mnfg's short-circuit rating or 100X nominal Ahr rating.- correct answer
>>>What is the minimum ampere interrupting capacity (AIC) for main overcurrent
protection on a battery bank rated at more than 2200 CCA or more than 500 Ahr?
False. "Readily accessible" defines entry into the engine room in an emergency as
dangerous - use a remote battery switch.- correct answer >>>T or F: it is ok to mount a
battery switch inside an engine room, because ABYC startes that it must be located as
close to the batteries as practical.
Every 18 inches.- correct answer >>>How often (in inches) shall wire bundles be
supported?
Insulated Metallic Hanger Clamps- correct answer >>>What type of clamps are to be
used for supporting wire bundles when routed over engines and machinery?
40 lbs (E-11 Table XV)- correct answer >>>What tensile force must a 10 Gauge crimp
connector withstand for one minute?
36 inches- correct answer >>>What is the max allowed unsupported cable length for
battery cables?
True- correct answer >>>T or F: Running AC and DC conductors together is allowed so
long as the AC conductors are sheathed.
C. Unwanted open- correct answer >>>The most common electrical circuit problem in
marine applications is:
A. Short circuits
B. Too much continuity
C. Unwanted open
D. Inter circuit Short
D. Heat- correct answer >>>The primary by-product of excessive electrical resistance
is:
A. Increased Amperage
B. Increased Voltage
C. Reduced Ambient Temperature
,D. Heat
1 HP = 746 Watts- correct answer >>>One HP = how many watts?
D. TDR (time-domain reflectometer)- correct answer >>>What is the preferred tool for
tracing shorted and open circuits?
A. Ohm meter
B. Amp clamp
C. Volt meter
D. TDR (time-domain reflectometer)
0 AWG- correct answer >>>A technician is installing a cable run from the batteries to
the main DC panel board on a boat as part of a refit. The boat has a 12-volt system and
the distance form the panel to the batteries is 15 ft. The maximum current draw from the
panel is calculated at 90 amps. What guage cable should be used (minimum)?
Yellow- correct answer >>>DC grounded conductors on new boats that are also
equipped with AC systems should use what color insulated wire?
16 AWG- correct answer >>>What is the smallest guage wire allowed for unsheathed
wire runs through the boat?
False. Start batteries have a greater number of thinner plates within each cell.- correct
answer >>>T or F: Compared to deep cycle (house) batteries, cranking batteries will
have thicker lead plates to facilitate the higher, short-duration current draws.
Overcurrent protection must be located withing 7 inches of the power source unless
contained within a sheath, in which case it may be up to 40 inches away. If the power
source is a battery and the conductors are sheathed, OC may be up to 72 inches away.-
correct answer >>>Explain the "7-40-72" rule
Resetting mechanism cannot overrid over current interrupting mechanism. (Note: some
residential breakers are not trip free)- correct answer >>>What does "trip free" breaker
mean?
C. 14.1 V- correct answer >>>The maximum sustained charging voltage acceptable to
some gell cell battery manufacturers is:
A. 13.8 V
B. 14.5 V
C. 14.1 V
D. 13.2 Vll
0.050 points of specific gravity below other cells = bad cell.- correct answer >>>When
testing a wet-cell battery with a hydrometer, what threshold is used to determine a bad
cell?
, 1.260 - 1.285 (temperature dependent)- correct answer >>>When testing a wet-cell
battery with a hydrometer, what reading indicates a fully charged battery?
50%- correct answer >>>When testing a fully charged start battery for capacity with a
load tester, what % of CCA rating should be induced by the load to test resulting
voltage?
C. Between 150% and 200%- correct answer >>>Most engine-driven alternators are
optimally spun at what percentage of engine RPMs?
A. Between 10% and 50%
B. Less than 10%
C. Between 150% and 200%
D. Greater than 200%
False. the battery charger case shall be tied to the engine negative terminal/bus, along
with the negative output terminal of the battery charger, not at the battery charger case
itself.,- correct answer >>>T or F: A battery charger case shall be tied to the DC
negative output terminal at the battery charger.
In case of an internal short to the case, the AC grounding wire would not carry enough
current.- correct answer >>>Why do battery chargers require a separate case
connection to main AC grounding bus and Engine negative / DC grounding bus?
No smaller than 1 size below the DC current carrying conductors between the charger
and batteries - provided OC protection on positive DC output is no greater than 135% of
DC grounding cable ampacity and conductor is no smaller than 16 AWG.- correct
answer >>>What is the minimal wire size required for a battery charger case connection
to DC ground/engine negative?
Class T fuse rated for appropriate AIC- correct answer >>>What device is typically
found to satisfy the required OC protection between a battery charger and the batteries?
Batteries will feed back into solar array or wind generator coil and discharge (possibly
damage). Note: many voltage regulators have integral blocking diodes.- correct answer
>>>What may happen to a solar array or wind generator used to charge batteries
without a blocking diode?
24 inches or more (unless waterproof!)- correct answer >>>How far above bilge water
level must a battery charger be mounted?
At least 24 inches- correct answer >>>How far away from a gasoline tank must a pre-
wired battery charger's AC connection plug be located?
False. (only when installed in location that required GFCI per ABYC E-11)- correct
answer >>>T or F: All marine inverters shall utilize an internal or external GFCI on their
AC outlets.
version with verified answers
Cranking- correct answer >>>Which type of battery generally recharges faster? Deep
cycle or cranking?
Wire brush and backing soda.- correct answer >>>What tool and common household
staple are used to clean battery terminals?
Most of the sulfuric acid has been absorbed into the lead plates, leaving mostly water in
the electrolyte.- correct answer >>>Why might a fully-discharged wet-cell type battery
freeze?
1 inch, 90 lbs or 2x the battery weight, for 1 minute in each direction.- correct answer
>>>Batteries must be secured to prevent movement of more than ______ inches in any
direction when a pulling force of _____ or _____, whichever is less, is applied through
the center of gravity of the battery for how long?
True- correct answer >>>T or F: it is ok to install batteries directly below an
uninterrupted fuel line?
Must be protected with dielectric insulating material- correct answer >>>What provision
must be in place on any fuel line located within 12 inches of a battery terminals?
80 F, 25 Amps, 10.5 Volts- correct answer >>>Define: Battery reserve capacity = the
number of minutes that a new, fully charged battery at ______ degrees F can be
continuously discharged at ______ amps while maintaining _____ volts (for a 12 v
battery)
90 minutes- correct answer >>>According to ABYC, what is the minimum battery
reserve capacity?
32 degrees F, 30 seconds, 7.2V- correct answer >>>Define: Marine Cranking Amps =
the discharge load, in amperes, that a new, fully-charged battery at _____ degrees F
can deliver for ______ seconds while maintaining a voltage of _____ volts (for a 12 v
battery).
0 degrees F, 30 seconds, 7.2V- correct answer >>>Define: Cold Cranking Amps = the
discharge load, in amperes, that a new, fully-charged battery at _____ degrees F can
deliver for ______ seconds while maintaining a voltage of _____ volts (for a 12 v
battery).
8 AWG- correct answer >>>What is the largest guage wire that may be connected to a
bettery with wing-nuts?
,800 CCA or 100 Ahr (exceptions: electronic equipment with battery backed memories;
safety equipment such as bilge pumps, alarms, CO detectors, bilge blowers; battery
chargers; I'm pressed current systems.- correct answer >>>Per ABYC E-10, a battery
switch must be installed in the positive conductor from each battery bank with a CCA
rating greater than ____ (or greater than _____ Ah if CCA rating not available).
AIC = 5000 Amps (E-11 table IV-A)- correct answer >>>What is the minimum ampere
interrupting capacity (AIC) for main overcurrent protection on a battery bank rated at 12
V, 1500 CCA?
AIC = 2X mnfg's short-circuit rating or 100X nominal Ahr rating.- correct answer
>>>What is the minimum ampere interrupting capacity (AIC) for main overcurrent
protection on a battery bank rated at more than 2200 CCA or more than 500 Ahr?
False. "Readily accessible" defines entry into the engine room in an emergency as
dangerous - use a remote battery switch.- correct answer >>>T or F: it is ok to mount a
battery switch inside an engine room, because ABYC startes that it must be located as
close to the batteries as practical.
Every 18 inches.- correct answer >>>How often (in inches) shall wire bundles be
supported?
Insulated Metallic Hanger Clamps- correct answer >>>What type of clamps are to be
used for supporting wire bundles when routed over engines and machinery?
40 lbs (E-11 Table XV)- correct answer >>>What tensile force must a 10 Gauge crimp
connector withstand for one minute?
36 inches- correct answer >>>What is the max allowed unsupported cable length for
battery cables?
True- correct answer >>>T or F: Running AC and DC conductors together is allowed so
long as the AC conductors are sheathed.
C. Unwanted open- correct answer >>>The most common electrical circuit problem in
marine applications is:
A. Short circuits
B. Too much continuity
C. Unwanted open
D. Inter circuit Short
D. Heat- correct answer >>>The primary by-product of excessive electrical resistance
is:
A. Increased Amperage
B. Increased Voltage
C. Reduced Ambient Temperature
,D. Heat
1 HP = 746 Watts- correct answer >>>One HP = how many watts?
D. TDR (time-domain reflectometer)- correct answer >>>What is the preferred tool for
tracing shorted and open circuits?
A. Ohm meter
B. Amp clamp
C. Volt meter
D. TDR (time-domain reflectometer)
0 AWG- correct answer >>>A technician is installing a cable run from the batteries to
the main DC panel board on a boat as part of a refit. The boat has a 12-volt system and
the distance form the panel to the batteries is 15 ft. The maximum current draw from the
panel is calculated at 90 amps. What guage cable should be used (minimum)?
Yellow- correct answer >>>DC grounded conductors on new boats that are also
equipped with AC systems should use what color insulated wire?
16 AWG- correct answer >>>What is the smallest guage wire allowed for unsheathed
wire runs through the boat?
False. Start batteries have a greater number of thinner plates within each cell.- correct
answer >>>T or F: Compared to deep cycle (house) batteries, cranking batteries will
have thicker lead plates to facilitate the higher, short-duration current draws.
Overcurrent protection must be located withing 7 inches of the power source unless
contained within a sheath, in which case it may be up to 40 inches away. If the power
source is a battery and the conductors are sheathed, OC may be up to 72 inches away.-
correct answer >>>Explain the "7-40-72" rule
Resetting mechanism cannot overrid over current interrupting mechanism. (Note: some
residential breakers are not trip free)- correct answer >>>What does "trip free" breaker
mean?
C. 14.1 V- correct answer >>>The maximum sustained charging voltage acceptable to
some gell cell battery manufacturers is:
A. 13.8 V
B. 14.5 V
C. 14.1 V
D. 13.2 Vll
0.050 points of specific gravity below other cells = bad cell.- correct answer >>>When
testing a wet-cell battery with a hydrometer, what threshold is used to determine a bad
cell?
, 1.260 - 1.285 (temperature dependent)- correct answer >>>When testing a wet-cell
battery with a hydrometer, what reading indicates a fully charged battery?
50%- correct answer >>>When testing a fully charged start battery for capacity with a
load tester, what % of CCA rating should be induced by the load to test resulting
voltage?
C. Between 150% and 200%- correct answer >>>Most engine-driven alternators are
optimally spun at what percentage of engine RPMs?
A. Between 10% and 50%
B. Less than 10%
C. Between 150% and 200%
D. Greater than 200%
False. the battery charger case shall be tied to the engine negative terminal/bus, along
with the negative output terminal of the battery charger, not at the battery charger case
itself.,- correct answer >>>T or F: A battery charger case shall be tied to the DC
negative output terminal at the battery charger.
In case of an internal short to the case, the AC grounding wire would not carry enough
current.- correct answer >>>Why do battery chargers require a separate case
connection to main AC grounding bus and Engine negative / DC grounding bus?
No smaller than 1 size below the DC current carrying conductors between the charger
and batteries - provided OC protection on positive DC output is no greater than 135% of
DC grounding cable ampacity and conductor is no smaller than 16 AWG.- correct
answer >>>What is the minimal wire size required for a battery charger case connection
to DC ground/engine negative?
Class T fuse rated for appropriate AIC- correct answer >>>What device is typically
found to satisfy the required OC protection between a battery charger and the batteries?
Batteries will feed back into solar array or wind generator coil and discharge (possibly
damage). Note: many voltage regulators have integral blocking diodes.- correct answer
>>>What may happen to a solar array or wind generator used to charge batteries
without a blocking diode?
24 inches or more (unless waterproof!)- correct answer >>>How far above bilge water
level must a battery charger be mounted?
At least 24 inches- correct answer >>>How far away from a gasoline tank must a pre-
wired battery charger's AC connection plug be located?
False. (only when installed in location that required GFCI per ABYC E-11)- correct
answer >>>T or F: All marine inverters shall utilize an internal or external GFCI on their
AC outlets.
