ABYC MARINE ELECTRICAL UPDATED EXAM
SCRIPT QUESTIONS AND ANSWERS SURE A+
✔✔AIC = 2X mnfg's short-circuit rating or 100X nominal Ahr rating. - ✔✔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. - ✔✔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.
✔✔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.
- ✔✔Explain the "7-40-72" rule
✔✔Resetting mechanism cannot overrid over current interrupting mechanism. (Note:
some residential breakers are not trip free) - ✔✔What does "trip free" breaker mean?
✔✔C. 14.1 V - ✔✔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. - ✔✔When testing a wet-
cell battery with a hydrometer, what threshold is used to determine a bad cell?
✔✔1.260 - 1.285 (temperature dependent) - ✔✔When testing a wet-cell battery with a
hydrometer, what reading indicates a fully charged battery?
,✔✔50% - ✔✔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% - ✔✔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., - ✔✔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. - ✔✔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. -
✔✔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 - ✔✔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. -
✔✔What may happen to a solar array or wind generator used to charge batteries
without a blocking diode?
✔✔24 inches or more (unless waterproof!) - ✔✔How far above bilge water level must a
battery charger be mounted?
✔✔At least 24 inches - ✔✔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) - ✔✔T or
F: All marine inverters shall utilize an internal or external GFCI on their AC outlets.
✔✔False. Most are not ignition protected. - ✔✔T or F: most GFCI outlets can be used in
a gasoline engine room
,✔✔False. Shore power neutral is tied to ground on the shore side. - ✔✔T or F: Because
the shore power connection is a power source, the neutral conductor should be tied to
ground at the point where it comes in to the boat (shore power cable connection)
✔✔Both. - ✔✔Tech A says that voltage supplied to the rotor controls the alternator
output voltage. Tech B says that the alternator output is proportional to the rotor voltage.
Which is correct, A, B, Both or Neither?
✔✔Tech A - ✔✔Tech A says that AC and DC are able to run together down the same
conductor. Tech B says this is technically impossible. Which is correct, A, B, neither or
both?
✔✔10' - ✔✔According to ABYC, what is the maximum distance allowed between a
boat's shore power connection and the main overcurrent protection device?
✔✔Equipment Leakage Current Interrupter - within 10 feet of shore power connection
unless an isolation transformer is located within 10' of shore power connection. -
✔✔What is an ELCI and where is it required to be installed?
✔✔False, they must be isolated to prevent shock hazard at the unutilizd shore power
connector pins. - ✔✔T or F: When more than one option for shore power inlet is
installed on a boat, the shore power neutrals shall be tied together on the boat.
✔✔At least 135% of isloator's nominal rating. (A-28.11.1) - ✔✔What ampacity is
required for wire and terminals connecting a galvanic islolator?
✔✔Ampacity < 20 Amps, voltage drop across terminals < 50 mV @ 20 A flow, no
separation with a one-minute pull of 6 lb force. - ✔✔What is the general rule for use of
friction connectors?
✔✔> 25 degrees above ambient - ✔✔When measuring temperature to determine
potential electrical issues involving excessive connector resistance, what is the
threshold for concern?
✔✔B. Not be grounded on the boat - ✔✔According to the ABYC, the shore-power
grounded conductor should:
A. Be connected to the AC neutral
B. Not be grounded on the boat
C. Be connected to the engine common positive terminal or its bus
D. Be tied to the battery isolator
✔✔A. Polarity check of shore cord - ✔✔If a customer complains about receiving shocks
from her boat when shore power is active, the technican should first test:
, A. Polarity check of shore cord
B. Polarity check of the battery system
C. Current Leakage Test
D. Converter voltage check
✔✔B. Check the voltage at the dock pedestal - ✔✔A customer is complaining about
low-voltage at the AC panel. What should you do first?
A. Re-calibrate the panel meter
B. Check the voltage at the dock pedestal
C. Check the polarity indicator
D. Replace the overcurrent device
✔✔C. An open neutral - ✔✔A customer notes a reverse-polarity problem. All of the
following are likely causes, except:
A. Improperly wired shore power cord
B. Improperly wired shore power inlet receptacle
C. An open neutral
D. Reversal of the hot and neutral conductors in the AC panel feeder cable
✔✔D. All of the above are possible - ✔✔What is a likely cause of non-functioning
galvanic isolator?
A. a shorted isolator diode
B. Improper current rating of the isolator diode
C. An on-board neutral-to-ground connection
D. All of the above are possible
✔✔D. Burned out 120V appliance - ✔✔An "open Neutral" conductor in a 240V/120V
shore power system will most likely show up as:
A. Nuisance tripping of the AC main breaker
B. Nuisance tripping of an appliance branch circuit breaker
C. A loud humming noise emitted from the TV
D. Burned out 120V appliance
✔✔True (provided the generator's self-limiting current, AKA "overload current", does not
exceed 120% of it's rated current output) - ✔✔T or F: Generators that are "self-limiting"
do not require overcurrent protection if the conductors used are of sufficient ampacity
and sized for maximum current available.
✔✔Mega ohm meter (AKA "merger"), 1 M Ohm - ✔✔What tool is used to test the
insulation integrity of a generator windings and what is the generally accepted Mimimal
measurement?
✔✔C. Excessive voltage drop across the remote starter switch - ✔✔A customer
complains that her generator will start from the local control panel at the generator, but
SCRIPT QUESTIONS AND ANSWERS SURE A+
✔✔AIC = 2X mnfg's short-circuit rating or 100X nominal Ahr rating. - ✔✔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. - ✔✔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.
✔✔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.
- ✔✔Explain the "7-40-72" rule
✔✔Resetting mechanism cannot overrid over current interrupting mechanism. (Note:
some residential breakers are not trip free) - ✔✔What does "trip free" breaker mean?
✔✔C. 14.1 V - ✔✔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. - ✔✔When testing a wet-
cell battery with a hydrometer, what threshold is used to determine a bad cell?
✔✔1.260 - 1.285 (temperature dependent) - ✔✔When testing a wet-cell battery with a
hydrometer, what reading indicates a fully charged battery?
,✔✔50% - ✔✔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% - ✔✔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., - ✔✔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. - ✔✔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. -
✔✔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 - ✔✔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. -
✔✔What may happen to a solar array or wind generator used to charge batteries
without a blocking diode?
✔✔24 inches or more (unless waterproof!) - ✔✔How far above bilge water level must a
battery charger be mounted?
✔✔At least 24 inches - ✔✔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) - ✔✔T or
F: All marine inverters shall utilize an internal or external GFCI on their AC outlets.
✔✔False. Most are not ignition protected. - ✔✔T or F: most GFCI outlets can be used in
a gasoline engine room
,✔✔False. Shore power neutral is tied to ground on the shore side. - ✔✔T or F: Because
the shore power connection is a power source, the neutral conductor should be tied to
ground at the point where it comes in to the boat (shore power cable connection)
✔✔Both. - ✔✔Tech A says that voltage supplied to the rotor controls the alternator
output voltage. Tech B says that the alternator output is proportional to the rotor voltage.
Which is correct, A, B, Both or Neither?
✔✔Tech A - ✔✔Tech A says that AC and DC are able to run together down the same
conductor. Tech B says this is technically impossible. Which is correct, A, B, neither or
both?
✔✔10' - ✔✔According to ABYC, what is the maximum distance allowed between a
boat's shore power connection and the main overcurrent protection device?
✔✔Equipment Leakage Current Interrupter - within 10 feet of shore power connection
unless an isolation transformer is located within 10' of shore power connection. -
✔✔What is an ELCI and where is it required to be installed?
✔✔False, they must be isolated to prevent shock hazard at the unutilizd shore power
connector pins. - ✔✔T or F: When more than one option for shore power inlet is
installed on a boat, the shore power neutrals shall be tied together on the boat.
✔✔At least 135% of isloator's nominal rating. (A-28.11.1) - ✔✔What ampacity is
required for wire and terminals connecting a galvanic islolator?
✔✔Ampacity < 20 Amps, voltage drop across terminals < 50 mV @ 20 A flow, no
separation with a one-minute pull of 6 lb force. - ✔✔What is the general rule for use of
friction connectors?
✔✔> 25 degrees above ambient - ✔✔When measuring temperature to determine
potential electrical issues involving excessive connector resistance, what is the
threshold for concern?
✔✔B. Not be grounded on the boat - ✔✔According to the ABYC, the shore-power
grounded conductor should:
A. Be connected to the AC neutral
B. Not be grounded on the boat
C. Be connected to the engine common positive terminal or its bus
D. Be tied to the battery isolator
✔✔A. Polarity check of shore cord - ✔✔If a customer complains about receiving shocks
from her boat when shore power is active, the technican should first test:
, A. Polarity check of shore cord
B. Polarity check of the battery system
C. Current Leakage Test
D. Converter voltage check
✔✔B. Check the voltage at the dock pedestal - ✔✔A customer is complaining about
low-voltage at the AC panel. What should you do first?
A. Re-calibrate the panel meter
B. Check the voltage at the dock pedestal
C. Check the polarity indicator
D. Replace the overcurrent device
✔✔C. An open neutral - ✔✔A customer notes a reverse-polarity problem. All of the
following are likely causes, except:
A. Improperly wired shore power cord
B. Improperly wired shore power inlet receptacle
C. An open neutral
D. Reversal of the hot and neutral conductors in the AC panel feeder cable
✔✔D. All of the above are possible - ✔✔What is a likely cause of non-functioning
galvanic isolator?
A. a shorted isolator diode
B. Improper current rating of the isolator diode
C. An on-board neutral-to-ground connection
D. All of the above are possible
✔✔D. Burned out 120V appliance - ✔✔An "open Neutral" conductor in a 240V/120V
shore power system will most likely show up as:
A. Nuisance tripping of the AC main breaker
B. Nuisance tripping of an appliance branch circuit breaker
C. A loud humming noise emitted from the TV
D. Burned out 120V appliance
✔✔True (provided the generator's self-limiting current, AKA "overload current", does not
exceed 120% of it's rated current output) - ✔✔T or F: Generators that are "self-limiting"
do not require overcurrent protection if the conductors used are of sufficient ampacity
and sized for maximum current available.
✔✔Mega ohm meter (AKA "merger"), 1 M Ohm - ✔✔What tool is used to test the
insulation integrity of a generator windings and what is the generally accepted Mimimal
measurement?
✔✔C. Excessive voltage drop across the remote starter switch - ✔✔A customer
complains that her generator will start from the local control panel at the generator, but
