Introduction to Photovoltaic Systems - CA Author: David Burtt
Introduction to Photovoltaic Systems - CA
Introduction to Photovoltaic Systems Activity
System Costs and Incentives Activity
Question 1: System Costs and Incentives Question.
Question ID#: 2648
Question 1: Currently, approximately what percentage of PV systems installed are residential systems?
A: 40%.
B: 50%.
C: 70%.
D: 95%.
Question 2: System Costs and Incentives Question.
Question ID#: 2649
Question 2: What is the approximate total installed cost of a system?
A: $1.00 / watt.
B: $3.00 / watt.
C: $7.00 / watt.
D: $10.00 / watt.
Question 3: System Costs and Incentives Question
Question ID#: 2650
Question 3: Using $7.00 / watt, how much would an installed 4000 watt PV system cost after deducting a 30%
federal personal tax credit and a 35% personal state tax credit (for North Carolina)?
A: $32,000.
B: $9,800.
C: $8,400.
D: $5,800.
Question 4: System Costs and Incentives Question.
Question ID#: 2651
Question 4: Using the <a href="http://www.dsireusa.org/solar/index.cfm?ee=1&re=1&spv=1&st=0"
target="_blank">DSIRE web site</a>, which of the following states does NOT offer a personal tax credit?
A: Cost of the system.
B: Ease of installation.
C: Renewable energy source.
D: Use of DC electricity instead of AC electricity.
Photovoltaic Components and System Design Activity
Photovoltaic Components and System Design Activity (Continued)
Question 6: Photovoltaic Components and System Design Question.
Question ID#: 2655
Question 6: Which of the following is NOT a type of PV cell?
A: Mono-phosphorous.
B: Multi-crystalline.
C: Mono-crystalline.
D: Amorphous.
Question 7: Photovoltaic Components and System Design Question.
Question ID#: 2656
Question 7: Each PV cell produces approximately how many volts?
A: .25 volt.
B: .5 volt.
C: 1 volt.
D: 5 volts.
Question 8: Photovoltaic Components and System Design Question.
Question ID#: 2657
Question 8: In a regular direct grid-tied PV system, which of the following is true?
A: AC disconnect.
B: DC diconnect.
C: Inverter.
D: Combiner box.
Question 10: Photovoltaic Components and System Design Question.
Question ID#: 2659
Question 10: What exactly does an inverter do?
A: It converts a square wave to a sine wave.
B: It converts DC electricity to AC electricity.
C: It converts sunlight into DC electricity.
D: It converts AC electricity to DC electricity.
Question 11: Photovoltaic Components and System Design Question.
Question ID#: 2660
Question 11: Microinverters would work best for which of the following?
A: Solar farm with 500 or more modules.
B: Commercial project with 100-150 modules.
C: Residential project with 50-70 modules.
D: Residential project with 10-15 modules.
Question 12: Photovoltaic Components and System Design Question.
Question ID#: 2661
Question 12: Which of the following would be the worst direction for a PV module to face?
A: South.
B: Southwest.
C: North.
D: West.
Question 13: Photovoltaic Components and System Design Question.
Question ID#: 2662
Question 13: Which of the following is a measure of irradiance?
A: Irradiance and visibility.
B: Current and Irradiance.
C: Current and Voltage.
D: Standard testing conditions.
Question 16: Photovoltaic Components and System Design Question.
Question ID#: 2665
Question 16: If a module has an Imp (rated maximum operating current) of 9 amps and a Vmp (rated maximum
operating voltage) of 20 volts, what is the Mpp (maximum power point/rated power)?
A: 150 watts.
B: 180 watts.
C: 29 watts.
D: 209 watts.
Question 17: Photovoltaic Components and System Design Question.
Question ID#: 2666
Question 17: If the light intensity increases from 800 watts / square meter to 1,100 watts / square meter and
cell temperature remains the same, what will happen to the energy output of a module?
A: It will go up.
B: It will go down.
C: It will stay the same.
D: It will spike and then return to the normal output.
Question 18: Photovoltaic Components and System Design Question.
Question ID#: 2667
Question 18: If everything else stays the same, which cell temperature will allow the module to produce the
most amount of energy?
A: 35°C (95°F).
B: 45°C (113°F).
C: 55°C (131°F).
D: 65°C (149°F).
Question 19: Photovoltaic Components and System Design Question.
Question ID#: 2668
Question 19: To take advantage of the most peak sun hours in a day, which technology would you use?
A: Fixed latitude tilt.
B: Fixed latitude + 50°tilt.
C: Single axis tracking.
D: Dual axis tracking.
Question 20: Photovoltaic Components and System Design Question.
Question ID#: 2669
Question 20: There are many methods available for mounting a PV system. Which of the following is NOT a
mounting method?
A: 25 volts.
B: 250 volts.
C: 70 volts.
D: 175 volts.
Question 22: Installing a System - Background Question.
Question ID#: 2672
Question 22: You have a string of 10 modules wired in series, and each one is rated 25 volts and 7 amps. You
have a total of 5 strings combined in parallel. What will the total amperage of your system be?
A: 7 amps.
B: 35 amps.
C: 50 amps.
D: 125 amps.
Question 23: Installing a System - Background Question.
Question ID#: 2673
Question 23: You have 40 modules that you would like to use. Each one is rated at 200 watts, 22 volts, and 9
amps. What is the best way to wire the system so that the array will stay within a 300 - 500 volt inverter input
voltage window?
A: 2 strings of 20 modules.
B: 3 strings of 13 modules.
C: 4 strings of 10 modules.
D: 5 strings of 8 modules.
Question 24: Installing a System - Background Question.
Question ID#: 2674
Question 24: Which part of PV system wiring should be installed last, after wiring the modules together?
A: 680.
B: 690.
C: 694.
D: 705.
7 kW System Design - Array Activity
Question 26: 7 kW System Design - Array Question.
Question ID#: 2677
Question 26: What kind of system did we design for our 7 kW installation?
A: Off-grid.
B: Grid-tied.
C: Grid-tied with battery backup.
D: Grid-tied with generator backup.
Question 27: 7 kW System Design - Array Question.
Question ID#: 2678
Question 27: Which of the following did we use for our location's minimum temperature?
A: Record Low Temperature.
B: Average Low Temperature.
C: ASHRAE Extreme Annual Mean Minimum Dry Bulb Temperature.
D: ASHRAE 100 Year Low Temperature.
Question 28: 7 kW System Design - Array Question.
Question ID#: 2679
Question 28: With the help of a string sizer, we decided to install 11 modules in series in 3 parallel strings.
Our module Vmp was 30 volts. What was our DC system voltage?
A: 111 V.
B: 240 V.
C: 330 V.
D: 407 V.
Question 29: 7 kW System Design - Array Question.
Question ID#: 2680
Question 29: With the help of a string sizer, we decided to install 11 modules in series in 3 parallel strings.
Our module Isc was 8.18 A. Not taking any other factors into account, what was our DC system amperage?
A: PV wire or USE-2.
B: RHW-2 or THHN.
C: XHHW or PV wire.
D: RHW-2 or RHH.
Question 31: 7 kW System Design - Array Question.
Question ID#: 2682
Question 31: Which of the following is true about connectors on PV modules?
A: They must be labeled "Sunlight Resistant".
B: They must be a latching or locking type.
C: They cannot be a latching or locking type.
D: They must contain the marking: "AC Source Circuits."
Question 32: 7 kW System Design - Array Question.
Question ID#: 2683
Question 32: Which of the following does NOT affect wire sizing?
A: Location.
B: Continuous duty.
C: Voltage drop.
D: Cell type.
Question 33: 7 kW System Design - Array Question.
Question ID#: 2684
Question 33: Which of the following is the multiplier used to account for irradiance when sizing PV circuit
conductors?
A: 1.16.
B: 1.25.
C: 1.56.
D: 1.78.
Question 34: 7 kW System Design - Array Question.
Question ID#: 2685
Question 34: The 2011 NEC requires that the disconnecting means be within sight of the location of the fuse
or integral with fuse holder. Which of the following pieces of equipment has been developed to deal with this
issue?
A: Bipolar PV modules.
B: Combiner box with integrated disconnect.
C: DC disconnect.
D: AFCI protection device.
Question 35: 7 kW System Design - Array Question.
Question ID#: 2686
Question 35: Inside a building, wiring cannot be installed within 10 inches of the roof decking unless:
A: 10 A.
B: 14 A.
C: 15 A.
D: 30 A.
Question 37: 7 kW System Design - Array Question.
Question ID#: 2688
Question 37: The total current on the PV output circuit from the PV modules is 24.54 amps. After adjusting for
continuous duty and irradiance, what is the calculated ampacity?
A: 38.3 A.
B: 36.3 A.
C: 30.7 A.
D: 24.5 A.
Question 38: 7 kW System Design - Array Question.
Question ID#: 2689
Question 38: What was the maximum operating current in our 7kW system? (Hint: Look at the inverter.)
A: 29 A.
B: 32 A.
C: 34 A.
D: 37 A.
Question 39: 7 kW System Design - Array Question.
Question ID#: 2690
Question 39: Which of the following is a new requirement in the 2011 NEC?
A: PV systems on dwelling units must be grounded.
B: AFCI (DC) protection is now required.
C: Upon entry into a building, PV system wiring can be installed in metallic raceways.
D: All of article 690 is new.
Question 40: 7 kW System Design - Array Question.
Question ID#: 2691
Question 40: In the example system, which of the following PV system components are wired directly to the
inverter?
A: A permanent plaque or directory identifying the location of each power source disconnecting means.
B: The contact information for the PV installer.
C: The nameplate rating of the inverter.
D: A label with the location of the AC disconnecting means.
Question 42: 7 kW System Design - Signage Question.
Question ID#: 2694
Question 42: A warning label applied by the _________ must be on the utility-interactive inverter stating the
following: WARNING ELECTRIC SHOCK HAZARD--- IF A GROUND FAULT IS INDICATED, NORMALLY
GROUNDED CONDUCTORS MAY BE UNGROUNDED AND ENERGIZED.
A: Home owner.
B: Inspector.
C: Installer.
D: Power company.
Question 43: 7 kW System Design - Signage Question.
Question ID#: 2695
Question 43: PV power source conductors must be marked with which of the following phrases?
A: Photovoltaic Power Source.
B: Photovoltaic DC Wiring.
C: Photovoltaic Conductors.
D: Source Circuit Wiring.
Question 44: 7 kW System Design - Signage Question.
Question ID#: 2696
Question 44: A permanent label must be applied by the installer at the PV DC power source disconnect and
must indicate all of the following EXCEPT:
A: The rated maximum power point current and voltage.
B: The maximum system voltage.
C: The short circuit current.
D: The number of modules wired in series.
Question 45: 7 kW System Design - Signage Question.
Question ID#: 2697
Question 45: PV systems with Ground Fault protection shall have a label stating the following (generally
located at the inverter):
A: Equipment grounding conductor.
B: Grounded conductor.
C: Main bonding jumper.
D: System bonding jumper.
Question 47: Grounding Question.
Question ID#: 2700
Question 47: Equipment grounding conductors for PV circuits having overcurrent protection must be sized to
the rating of the PV circuit overcurrent device in accordance with ________.
A: 250.121.
B: 250.52.
C: Table 250.122.
D: Table 250.66.
Question 48: Grounding Question.
Question ID#: 2701
Question 48: The DC Grounding Electrode Conductor is sized in accordance with _______.
A: 250.122.
B: 250.166.
C: 250.121.
D: 250.66.
Question 49: Grounding Question.
Question ID#: 2702
Question 49: Where exposed and subject to physical damage, array equipment grounding conductors smaller
than _______ AWG must be protected by a raceway or cable armor.
A: #10.
B: #8.
C: #6.
D: #4.
Question 50: Grounding Question.
Question ID#: 2703
Question 50: Which of the following statements about system grounding for PV systems is true?