NABCEP PRACTICE EXAM
QUESTIONS & ANSWERS(RATED A+)
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 energy use per month? - ANSWER68kWh
What kind of ground faults do most inverters detect? - ANSWERDC
Current carrying ability of a conductor (wire) is called... - ANSWERAmpacity
According to ohms law and voltage drop, the relationship between voltage and current
is... - ANSWERProportional
An array in sacramento California in August is not producing as expected. Which of the
following is a likely problem? - ANSWERDecreased ac wire size and voltage loss
When using a digital multimeter, what is the first thing you should do? -
ANSWERInspect the meter
Which is the worst design error? - ANSWERDifferent tilt angles in a PV source circuit
The low design temperature is -20 degrees celsius and the Voc temperature correction
factor for your PV is -0.34%/degrees celsius. The characteristics of your module are Isc
= 8A, Voc = 29V. How many modules can you put in the series for an inverter that
cannot go over 500V? (-20°C - 25°C = -45°C) (-45°C × -0.34%/°C = 15.3% increase
Voc) (1.15 × 37Voc = 42.6V cold) (500V/42.6V= ?) - ANSWER11 (11.7)
MPPT is for... - ANSWERoptimizing power from a PV array
Concentrated PV... - ANSWERonly works with direct sunlight
Fall protection should be used at heights over... - ANSWER6 feet
Parallel PV circuit connections increase... - ANSWERcurrent
Optimal tilt for off-grid PV system in the winter... - ANSWERLatitude +15%
For a TRANSFORMELESS INVERTER, which type of wire should be used when
exposed to the elements outdoor on PV source circuits? - ANSWERPV wire
Bypass diodes are located in the... - ANSWERPV module
A PV array at a higher elevation would tend to produce more... - ANSWERCurrent
QUESTIONS & ANSWERS(RATED A+)
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 energy use per month? - ANSWER68kWh
What kind of ground faults do most inverters detect? - ANSWERDC
Current carrying ability of a conductor (wire) is called... - ANSWERAmpacity
According to ohms law and voltage drop, the relationship between voltage and current
is... - ANSWERProportional
An array in sacramento California in August is not producing as expected. Which of the
following is a likely problem? - ANSWERDecreased ac wire size and voltage loss
When using a digital multimeter, what is the first thing you should do? -
ANSWERInspect the meter
Which is the worst design error? - ANSWERDifferent tilt angles in a PV source circuit
The low design temperature is -20 degrees celsius and the Voc temperature correction
factor for your PV is -0.34%/degrees celsius. The characteristics of your module are Isc
= 8A, Voc = 29V. How many modules can you put in the series for an inverter that
cannot go over 500V? (-20°C - 25°C = -45°C) (-45°C × -0.34%/°C = 15.3% increase
Voc) (1.15 × 37Voc = 42.6V cold) (500V/42.6V= ?) - ANSWER11 (11.7)
MPPT is for... - ANSWERoptimizing power from a PV array
Concentrated PV... - ANSWERonly works with direct sunlight
Fall protection should be used at heights over... - ANSWER6 feet
Parallel PV circuit connections increase... - ANSWERcurrent
Optimal tilt for off-grid PV system in the winter... - ANSWERLatitude +15%
For a TRANSFORMELESS INVERTER, which type of wire should be used when
exposed to the elements outdoor on PV source circuits? - ANSWERPV wire
Bypass diodes are located in the... - ANSWERPV module
A PV array at a higher elevation would tend to produce more... - ANSWERCurrent
