NABCEP PV ASSOCIATE RETAKE EXAM|RETAKE PRACTICE
EXAM LATEST EXAM 2024|ALL QUESTIONS AND CORRECT
ANSWERS UPDATED
An off-grid installation has a 1HP pump that is on 10% of the time and a 20W
light that is on 100% of the time. What is the monthly energy use? - ANSWER-
68KWh
1HP = 746W
746W * 0.1 * 24hours * 30days =
53712Wh 20W * 24hrs * 30days =
14400Wh
14400 + 53712 = 68112Wh
68kWh
What kind of ground faults do most inverters detect? - ANSWER-DC
Inverters detect dc ground faults. AC ground faults are detected on the AC side
of the inverter at the distribution paned (MSP, load center). Most inverters are
not connected to high or medium voltage. Medium voltage is thousands of
volts, large utility scale inverters are connected to medium voltage via a
transformer
Current carrying ability of a conductor (wire) is called - ANSWER-Ampacity
According to ohms law and voltage drop, the relationship between voltage
drop and current is - ANSWER-Proportional. Ohms law: V = I*R
More current makes more voltage drop. This is a reason why we need a
larger wire with more current, so the wire resistance is less with a larger
wire and there will be less voltage drop.
,An array in a hot and dry place is not producing as expected in summer time.
Which of the following is NOT a likely problem:
a) Decreased ac wire size and voltage loss
,b) String size too short
C) String size too long
D) Soiling - ANSWER-C) String size too short. When it is hot, voltage can be
low. Too long of a string would be a problem when it is too cold not too hot.
When using a digital multimeter, what is the first thing you should do? -
ANSWER-Inspect the meter.
Always inspect first, look before you touch
is the worst design error?
A) BIPV on a commercial job
B) A fast-growing tree to the north of an array in Idaho
C) PV at 5-degree tilt at 40 degrees latitude
D) Different tilt angles in a PV source circuit - ANSWER-D) Different tilt or
azimuth operation within a source circuit is bad. Series connections should not
have different orientations
MPPT is for - ANSWER-MPPT is maximum power point tracking and will
optimize the energy
harnessed from PV. Some inverters have multiple MPPTs. Charge controllers
often, but don't always, have MPPTs
Concentrated PV:
A) Only works with direct sunlight
B) Usually has a single axis tracker
C) Will get 30% power during cloudy conditions
D) Is using heat to make electricity- ANSWER-A) Only works in direct sunlight.
usually works with 2- axis trackers to always point at the sun and will not work
at all in cloudy conditions. Concentrated PV
=! Concentrating solar thermal
, Fall protection should be used at heights over - ANSWER-6 feet
Parallel PV circuit connections increase - ANSWER-Parallel increase current.
Series increase voltage
Optimal tilt for off-grid PV system in the winter - ANSWER-Latitude + 15 degrees
is Optimal tilt to maximize winter production. The sun is lower in the winter,
requiring a higher tilt angle
EXAM LATEST EXAM 2024|ALL QUESTIONS AND CORRECT
ANSWERS UPDATED
An off-grid installation has a 1HP pump that is on 10% of the time and a 20W
light that is on 100% of the time. What is the monthly energy use? - ANSWER-
68KWh
1HP = 746W
746W * 0.1 * 24hours * 30days =
53712Wh 20W * 24hrs * 30days =
14400Wh
14400 + 53712 = 68112Wh
68kWh
What kind of ground faults do most inverters detect? - ANSWER-DC
Inverters detect dc ground faults. AC ground faults are detected on the AC side
of the inverter at the distribution paned (MSP, load center). Most inverters are
not connected to high or medium voltage. Medium voltage is thousands of
volts, large utility scale inverters are connected to medium voltage via a
transformer
Current carrying ability of a conductor (wire) is called - ANSWER-Ampacity
According to ohms law and voltage drop, the relationship between voltage
drop and current is - ANSWER-Proportional. Ohms law: V = I*R
More current makes more voltage drop. This is a reason why we need a
larger wire with more current, so the wire resistance is less with a larger
wire and there will be less voltage drop.
,An array in a hot and dry place is not producing as expected in summer time.
Which of the following is NOT a likely problem:
a) Decreased ac wire size and voltage loss
,b) String size too short
C) String size too long
D) Soiling - ANSWER-C) String size too short. When it is hot, voltage can be
low. Too long of a string would be a problem when it is too cold not too hot.
When using a digital multimeter, what is the first thing you should do? -
ANSWER-Inspect the meter.
Always inspect first, look before you touch
is the worst design error?
A) BIPV on a commercial job
B) A fast-growing tree to the north of an array in Idaho
C) PV at 5-degree tilt at 40 degrees latitude
D) Different tilt angles in a PV source circuit - ANSWER-D) Different tilt or
azimuth operation within a source circuit is bad. Series connections should not
have different orientations
MPPT is for - ANSWER-MPPT is maximum power point tracking and will
optimize the energy
harnessed from PV. Some inverters have multiple MPPTs. Charge controllers
often, but don't always, have MPPTs
Concentrated PV:
A) Only works with direct sunlight
B) Usually has a single axis tracker
C) Will get 30% power during cloudy conditions
D) Is using heat to make electricity- ANSWER-A) Only works in direct sunlight.
usually works with 2- axis trackers to always point at the sun and will not work
at all in cloudy conditions. Concentrated PV
=! Concentrating solar thermal
, Fall protection should be used at heights over - ANSWER-6 feet
Parallel PV circuit connections increase - ANSWER-Parallel increase current.
Series increase voltage
Optimal tilt for off-grid PV system in the winter - ANSWER-Latitude + 15 degrees
is Optimal tilt to maximize winter production. The sun is lower in the winter,
requiring a higher tilt angle
