ABYC MARINE ELECTRICAL CERTIFICATION
EXAM WITH WELL ELLABORATED
ANSWERS(A+)
a. test with an RMS voltmeter - CORRECT_ANSWER_When a customer complains
of low inverter AC output voltage, the first thing the technician should do is:
a. test with an RMS voltmeter
b. replace the inverter
c. test with a calibrated averaging voltmeter
d. readjust the customer's voltmeter
c. Neither A nor B - CORRECT_ANSWER_Technician A says inverter AC backfeeding
is caused by improper switching of an external power source. Technician B says
that backfeeding is caused by DC reversed polarity. Which technician is correct?
a. Technician A
b. Technician B
c. Neither A nor B
d. Both A and B
,d. blocking mode - CORRECT_ANSWER_Which is not a correct mode of operation
of an inverter?
a. inverting mode
b. transfer mode
c. charging mode
d. blocking mode
a. connected to the boats AC ground - CORRECT_ANSWER_When an inverter is
producing AC power, the inverter output neutral conductor should be
a. connected to the boats AC ground
b. floating above ground
c. greater than 25,000 ohms below ground
d. greater than 25,000 ohms above ground
b. 169 Volts - CORRECT_ANSWER_A sine wave for "Shore Power" AC has an RMS
value of 120 volts. What is its peak value?
a. 120 Volts
b. 169 Volts
c. 208 Volts
d. 240 Volts
,d. use large cranking batteries - CORRECT_ANSWER_For proper inverter operation
it is important to do all of the following except
a. adequately size inverter output for connected loads
b. provide AC overcurrent circuit protection
c. provide DC overcurrent circuit protection
d. use large cranking batteries
D. 135% (see A-31.6.5.1.2, exception) - CORRECT_ANSWER_The inverter DC
grounding conductor may be one size smaller than than the minimum size
conductor required for the DC current carrying conductors providing the
overcurrent protection device in the DC positive conductor is rated no greater
than __________ of the ampacity of the DC grounding conductor and the
conductor is no smaller than 16 AWG.
A. 100%
B. 120%
C. 125%
D. 135%
a. 89 amps - CORRECT_ANSWER_A 2000 watt inverter is operating at 50%
capacity with a 90% effeciency rating. With a battery voltage of 12.6 volts how
many amps is the inverter drawing from the battery bank?
, a. 89 amps
b. 99 amps
c. 109 amps
d. 119 amps
b. 10.5 Volts - CORRECT_ANSWER_Most marine inverters will shut down
automatically when battery voltage falls below what voltage?
a. 9.7 Volts
b. 10.5 Volts
c. 11.7 Volts
d. 12 Volts
d. all of the above - CORRECT_ANSWER_lf a separate, independent AC powered
battery charger is fitted along with an inverter/charger, the independent AC
powered charger must be:
a. fitted with output protection fuses to protect the DC output
b. not be powered when the inverter is producing AC
c. fitted with an AC case grounding wire
d. all of the above
EXAM WITH WELL ELLABORATED
ANSWERS(A+)
a. test with an RMS voltmeter - CORRECT_ANSWER_When a customer complains
of low inverter AC output voltage, the first thing the technician should do is:
a. test with an RMS voltmeter
b. replace the inverter
c. test with a calibrated averaging voltmeter
d. readjust the customer's voltmeter
c. Neither A nor B - CORRECT_ANSWER_Technician A says inverter AC backfeeding
is caused by improper switching of an external power source. Technician B says
that backfeeding is caused by DC reversed polarity. Which technician is correct?
a. Technician A
b. Technician B
c. Neither A nor B
d. Both A and B
,d. blocking mode - CORRECT_ANSWER_Which is not a correct mode of operation
of an inverter?
a. inverting mode
b. transfer mode
c. charging mode
d. blocking mode
a. connected to the boats AC ground - CORRECT_ANSWER_When an inverter is
producing AC power, the inverter output neutral conductor should be
a. connected to the boats AC ground
b. floating above ground
c. greater than 25,000 ohms below ground
d. greater than 25,000 ohms above ground
b. 169 Volts - CORRECT_ANSWER_A sine wave for "Shore Power" AC has an RMS
value of 120 volts. What is its peak value?
a. 120 Volts
b. 169 Volts
c. 208 Volts
d. 240 Volts
,d. use large cranking batteries - CORRECT_ANSWER_For proper inverter operation
it is important to do all of the following except
a. adequately size inverter output for connected loads
b. provide AC overcurrent circuit protection
c. provide DC overcurrent circuit protection
d. use large cranking batteries
D. 135% (see A-31.6.5.1.2, exception) - CORRECT_ANSWER_The inverter DC
grounding conductor may be one size smaller than than the minimum size
conductor required for the DC current carrying conductors providing the
overcurrent protection device in the DC positive conductor is rated no greater
than __________ of the ampacity of the DC grounding conductor and the
conductor is no smaller than 16 AWG.
A. 100%
B. 120%
C. 125%
D. 135%
a. 89 amps - CORRECT_ANSWER_A 2000 watt inverter is operating at 50%
capacity with a 90% effeciency rating. With a battery voltage of 12.6 volts how
many amps is the inverter drawing from the battery bank?
, a. 89 amps
b. 99 amps
c. 109 amps
d. 119 amps
b. 10.5 Volts - CORRECT_ANSWER_Most marine inverters will shut down
automatically when battery voltage falls below what voltage?
a. 9.7 Volts
b. 10.5 Volts
c. 11.7 Volts
d. 12 Volts
d. all of the above - CORRECT_ANSWER_lf a separate, independent AC powered
battery charger is fitted along with an inverter/charger, the independent AC
powered charger must be:
a. fitted with output protection fuses to protect the DC output
b. not be powered when the inverter is producing AC
c. fitted with an AC case grounding wire
d. all of the above
