NABCEB Exam with all Correct & 100% Verified Answers
|Latest Version |Already Graded A+
The 2005 NEC allows marking conductors with colored tape, provided that they are larger than?
✔Correct Answer-6 AWG
Temporarily shorting the output terminals of a PV module will ✔Correct Answer-Have no effect on
the module
A _____ is a protective enclosure used to connect various module strings together ✔Correct
Answer-B Combiner box (used to connect conductors while junction boxes are used to switch wires
What is a correct color convention for DC wiring in a grounded PV array
Positive color?
Negative color?
Ground color? ✔Correct Answer-Positive is black, negative is red, ground is white
Ground must be white. Positive can be anything but white and green
Between the array and the inverter, you have ✔Correct Answer-A DC disconnect or an AC
disconnect.
Depends whether there is a battery bank or not. AC uses battery bank
A solar array has 12 Kyocera KC85T modules arranged in 2 strings of 6 modules per each string. What
do you expect to see as the output parameters under these STC conditions?
Vmp= 17.4 volts
Imp= 5.02 Amps ✔Correct Answer-104 volts at 10.04 amps
Need volts and amps in output
Volts: 6 modules X 17.4 volts = 104.4 volts
modules X volts
Amps: 2 strings X 5.02 amps = 10.04 amps
strings X amps
Which item does NOT require UL or equivalent listing?
a. concrete anchors
b. Surge protectors
c. Battery cables
d. Charge controllers ✔Correct Answer-A
, With the PV array mounted at ground level, which would normally be of the greatest concern over
the life of the system?
A. Overheating of the modules
B. Electrical hazards from exposed conductors open circuit voltages
C. Earthquake stresses on the modules
D. Physical damage to the array and wiring ✔Correct Answer-D
The best way to increase a PV array's output is to
A.Switch from stand alone to interactive
B. Decease your voltage drop by 18% with less wiring
C.Add 20% more PV modules
D. Switch from East facing to South facing on a roof slope that is within 10 degrees of latitude
✔Correct Answer-D max sunlight
A utility-interactive PV system with no batteries consists of 15, 100 watt modules in series that feed a
1500 watt inverter. The inverter output power is found to be 780 watts when the modules are
operating at 50°C with an irradiance level of 800 waat/m2. If three modules are observed to be
shaded, which conclusion is most likely?
A. The inverter input current is probably too low
B. The system is probably functioning properly
C. The inverter is probably not tracking maximum power
D. The modules probably do not have bypass diodes ✔Correct Answer-B. STC 25C, 75F, 1000 W/M2
Equation
1500 watts X .8 (80% irradiance from STC) X .91 (25 degrees over STC X .35 volt drop per degree
above STC) X .80 for system derating. = 874 Watts
close enough to 780 to assume working properly
What is the purpose of an inverter ✔Correct Answer-convert DV at one voltage to AC at the same
or another voltage
Sine wave inverters are required for connection to utility lines, because ✔Correct Answer-They are
the only inverters that have low enough harmonic distortion
When mounting a heavy inverter or other piece of equipment to a "drywall" type of wall, to provide
a solid attachment to the wall, it may be necessary to use
A. Thumb tacks
B. Plastic anchors
C. Plywood
D. Moly bolts ✔Correct Answer-C. Plywood
The width of the working space in front of an inverter that is 24 inches wide must be at least
A. 24 inches
B. 30 inches
C. 36 inches
|Latest Version |Already Graded A+
The 2005 NEC allows marking conductors with colored tape, provided that they are larger than?
✔Correct Answer-6 AWG
Temporarily shorting the output terminals of a PV module will ✔Correct Answer-Have no effect on
the module
A _____ is a protective enclosure used to connect various module strings together ✔Correct
Answer-B Combiner box (used to connect conductors while junction boxes are used to switch wires
What is a correct color convention for DC wiring in a grounded PV array
Positive color?
Negative color?
Ground color? ✔Correct Answer-Positive is black, negative is red, ground is white
Ground must be white. Positive can be anything but white and green
Between the array and the inverter, you have ✔Correct Answer-A DC disconnect or an AC
disconnect.
Depends whether there is a battery bank or not. AC uses battery bank
A solar array has 12 Kyocera KC85T modules arranged in 2 strings of 6 modules per each string. What
do you expect to see as the output parameters under these STC conditions?
Vmp= 17.4 volts
Imp= 5.02 Amps ✔Correct Answer-104 volts at 10.04 amps
Need volts and amps in output
Volts: 6 modules X 17.4 volts = 104.4 volts
modules X volts
Amps: 2 strings X 5.02 amps = 10.04 amps
strings X amps
Which item does NOT require UL or equivalent listing?
a. concrete anchors
b. Surge protectors
c. Battery cables
d. Charge controllers ✔Correct Answer-A
, With the PV array mounted at ground level, which would normally be of the greatest concern over
the life of the system?
A. Overheating of the modules
B. Electrical hazards from exposed conductors open circuit voltages
C. Earthquake stresses on the modules
D. Physical damage to the array and wiring ✔Correct Answer-D
The best way to increase a PV array's output is to
A.Switch from stand alone to interactive
B. Decease your voltage drop by 18% with less wiring
C.Add 20% more PV modules
D. Switch from East facing to South facing on a roof slope that is within 10 degrees of latitude
✔Correct Answer-D max sunlight
A utility-interactive PV system with no batteries consists of 15, 100 watt modules in series that feed a
1500 watt inverter. The inverter output power is found to be 780 watts when the modules are
operating at 50°C with an irradiance level of 800 waat/m2. If three modules are observed to be
shaded, which conclusion is most likely?
A. The inverter input current is probably too low
B. The system is probably functioning properly
C. The inverter is probably not tracking maximum power
D. The modules probably do not have bypass diodes ✔Correct Answer-B. STC 25C, 75F, 1000 W/M2
Equation
1500 watts X .8 (80% irradiance from STC) X .91 (25 degrees over STC X .35 volt drop per degree
above STC) X .80 for system derating. = 874 Watts
close enough to 780 to assume working properly
What is the purpose of an inverter ✔Correct Answer-convert DV at one voltage to AC at the same
or another voltage
Sine wave inverters are required for connection to utility lines, because ✔Correct Answer-They are
the only inverters that have low enough harmonic distortion
When mounting a heavy inverter or other piece of equipment to a "drywall" type of wall, to provide
a solid attachment to the wall, it may be necessary to use
A. Thumb tacks
B. Plastic anchors
C. Plywood
D. Moly bolts ✔Correct Answer-C. Plywood
The width of the working space in front of an inverter that is 24 inches wide must be at least
A. 24 inches
B. 30 inches
C. 36 inches
