WorksheetsSample Exam 1
Total questions: 70
Worksheet time: 35mins
An ammeter in combination with which other kind of meter could measure power?
Ohmmeter
Voltmeter
Energy meter
Pyranometer
You find a dc disconnect with an open door. You should assume:
Since you cannot open the door without the disconnect being off, then the disconnect is safe to work on.
That the disconnect is being worked on by another electrician.
That all conductors and terminals in the disconnect are energized.
That line and load are only energized in the open position.
How do you measure dc voltage?
Turn the voltmeter voltage to a dc voltage setting higher than you are going to measure and put the red probe on positive and the black probe on negative.
Put the volt clamp around the conductor you are going to measure and then turn on the voltmeter.
Put the volt clamp on the conductor after turning on the voltmeter.
Turn the meter to the power setting and then divide by current.
What is the best way of the following to avoid getting shocked?
Turning things off before you work on them.
Using double insulated tools.
Lockout tagout of PV modules when carrying them to the roof.
Grounding ungrounded conductors before working on them.
When calculating energy, which units should you use for the current in your equation?
A for Amperes
I for current
C for current
F for flow
Which device measures resistance?
Voltmeter
Ammeter
kWh meter
Megohmmeter
What is the first action to take when a ground fault is indicated by an inverter?
Diagnose and fix the ground fault
Close the dc disconnect
Open the dc disconnect
Disconnect the strings
What does irradiance on a dc PV source circuit affect the most?
Voltage
Resistance
Current
Coefficience
Which type of PV is developed from cast ingots?
Monocrystalline
Thin film CdTe
Thin film Gallium Arsenide
Polycrystalline
What is an example of a direct coupled PV system?
A PV system with a battery and no charge controller with the load designed, so that it does not overcharge the battery.
A PV system that is directly connected to the utility
PV and a load with no energy storage or utility connection
Every water pumping PV system is direct coupled
What is the most cost effective, yet sufficient method for marking for a PV label?
Handwriting with permanent marker
Engraving on a NEMA rated disconnect
Permanent sticker
Handwriting on permanent sticker indoors only
When the sun is shining on the PV arrays, under normal circumstances and for best production, the best thing to do is:
Open the disconnects
Short the conductors
Replace fuses
Close the disconnects
Which component most commonly has a fuse in a modern PV system?
Inverter
Dc-to-dc converter
PV module junction box
Dc combiner
What is the slope of a 4:12 roof?
14 degrees
18 degrees
23 degrees
27 degrees
What limits the maximum power rating of the largest load of an off-grid system?
the size of the battery
the size of the array
the size of the inverter plus any other power source
the size of the charge controller
What is used to connect the solar array to rafters?
Polyurethane
Nails
Graphene fasteners
Lag screws
What is BIPV?
PV that also replaces building materials
PV that can absorb solar energy from both sides to take advantage of reflected light
PV that is both positively and negatively grounded
PV that is transparent
What does autonomy refer to when sizing a battery bank?
The battery bank is consisting of only one type of battery chemistry
The battery cells are all connected in one series string
The battery management system can control the charge/discharge without human input
How long a battery bank can last without being charged
Where would you find information about SRECs and other solar incentives on a state-by-state basis?
Solarabcs.org website
IREC website
NREL website
DSIRE website
What is the impact of the temperature rating of the insulation of a conductor in a PV system design?
Ability of the wire to withstand fire
Ability of the wire to withstand smoke
Ability of the wire to carry current
Ability of the wire to withstand physical damage
What effect does a bypass diode have when activated due to a leaf covering a solar cell in a PV system?
Current
Voltage
Ohms
Amp hours
What would be the expected output at Standard Test Conditions for a PV module with 20 PV sources in series, each with a circuit Voc of 44V, Vmp of 35.2V, power of 305W, and Isc of 9.27A?
704V and 8.66A
600V and 8A
1000V and 8.2A
700V and 9.27A
What is an NRTL?
Nationally Recognized Testing Labs
National Renewable Testing Lab
A federal government agency that oversees renewable energy incentives on a state level.
A federal government agency that oversees tariffs on renewable energy equipment.
What is the power of the array at STC?
10kW
110kW
1000W
40kW
Which of the following is the worst design flaw when an inexperienced person designs a PV system?
Multiple orientations within a PV source circuit
Multiple orientations for different PV source circuits
Occasional shading on a module that is in a PV source circuit that has its own MPP
Microinverters used on a commercial job
What is the shape of a typical monocrystalline solar wafer?
Circular
Square
Rectangular
Square with rounded corners
Which of the following can change DC power into AC power with a predetermined specific frequency and voltage?
Inverter
Power converting utility
Step up transformer
Step down transformer
What does MPPT stand for?
Maximum payback period time
Maximum power performance track
Maximum power point tracking
Minimum peak performance time
Where do PV source circuits and PV output circuits meet?
AC combiner
PV array
DC combiner
Inverter MPP inputs
What contributes to determining the ampacity or the temperature rating of a conductor?
Insulation
Insolation
Fill factor
Sealing raceways
What kind of PV system is used so that people have power if the utility ceases to exist, but can still work with the utility?
Stand-alone
Direct-coupled
Multimode
Grid-tied hybrid
On a southeast facing residential rooftop, what is the most common type of mounting system?
BIPV
Flush mounted rack mount
Tilt up rack mount
Ballasted
If you are sizing a PV system on a building for a location with net-metering, what is the best way of the following to size the system?
a. Multiply load factor by power factor by energy usage
b. Size the system based on energy usage, budget and available space
c. Size the system based on offsetting the entire electric bill always
d. Size the system based on how much will fit on the roof
If we wanted to calculate an average power, what would we do mathematically?
a. Take demand charges and divide by time
b. Divide energy by time
c. Divide Ah by time
d. Divide resistance by power
In dry places, what would typically be the most common type of maintenance on a PV system?
a. Removing leaves
b. Washing
c. Shade analysis
d. Moisturizing
Which characteristics of a wire would lead to more voltage drop?
a. Long and wide
b. Short and wide
c. Long and thin
d. Short and thin
Which device is used to determine that series wiring has been done correctly?
Clamp on ammeter
Digital multimeter
Megger
Pyranometer
Who will typically be required to approve the plans of a PV system?
Local contractor board
State Public Utility Commission (PUC)
Utility
Authority Having Jurisdiction (AHJ)
Ground fault detection on a typical interactive inverter is most often due to what?
at the PV array
at the utility meter
at the Earth
at the loads
A 16A interactive inverter that operates at a 240V utility nominal voltage will produce how much power when clipping?
38kW
3840W
15kW
0.038MW
What is the solar altitude angle?
The angle between straight overhead and the sun
The angle between 45 degrees above the ground and the sun
The angle between the horizon and the sun
The angle between sunrise and sunset
MPPT is for
Optimizing energy from the utility
Getting the most energy from a battery with a MPPT inverter
Optimizing power from a PV array
Tracking the sun with a 2-axis tracker
Parallel PV circuit connections increase
Voltage
Current
Resistance
EMF
What is the most appropriate and cost-effective rating of an enclosure for exposed circuit conductors mounted on an outside wall?
NEMA 3R
NEMA 11
NEMA 4X
NEMA 12
Which test conditions have higher voltage?
STC
PTC
CEC
NOCT
Which is the best tilt angle for annual production in most of the USA (temperate latitudes)?
Latitude +15 degrees
Latitude -15 degrees
30 degrees
Longitude tilt
Current carrying ability of a conductor (wire) is called
Ampacity
Amps
Inductance
Insolation
According to Ohm's law and voltage drop, what is the relationship between voltage drop and current?
Proportional
Inversely proportional
Directly inverse
Inversely direct
When using a digital multimeter, what is the first thing you should do?
Turn the meter on
Inspect the meter
Touch the black lead to the white wire
Touch the black lead to the black wire
If available roof area is 12m² and the PV is 19% efficient, then what is the most PV that will fit?
4.5kW
2.2kW
1.8kW
3.3kW
Fall protection should be used at heights over
4 feet
2 feet
3 feet
6 feet
Which addresses environmental hazards on a safety plan?
SDS
Fall protection
Ladder safety
Nearest hospital address
Who is responsible for making requirements for electrical safety for employees?
Employer
Employee
OSHA
NEC
What is one of the aspects for which PV modules are tested by CSA to the UL 1703 and UL 61730 standards?
Power production over long periods of time
Fire safety
Maximum performance in cloudy conditions
Temperatures down to -60C
How do residential rooftop mounting systems typically secure to a rooftop to prevent being blown away by the wind?
Lag screws into rafters or purlins
Nails into sheathing
Flashings
Ballasts
What are the typical voltages in North American homes?
110/208 Vac
277/480 Vac
100 Vac
120/240 Vac
What is the total energy produced when a 500W/m² solar irradiance is applied over an area for 4 hours?
20kWh/m²
2kWh/m²
2kW/m²
5kW
When considering the critical design month for a stand-alone PV system, which scenario is typically most challenging?
Best insolation and most load usage
Worst insolation and most load usage
Worst insolation and least load usage
Best insolation and least load usage
What is the recommended method for roofers to prevent water intrusion at structural attachments?
Caulking around the screw
Extrusions
Flashing
Syzygy
How much power can a 20% efficient PV system generate from a 25 square meter area?
3000W
4.5kW
4000W
5kW
What do you do if an inverter indicates a ground fault after turning off the PV system after opening all of the disconnects?
Reset the inverter so that it will work
Replace the fuse in the inverter
Unground the system
Look under the array for lose or bare wires
What is the solar window?
A place where the sun can be throughout the year, often defined as between 9am and 3pm.
A transparent device used to determine sun paths
The location in the sky where the sun will never be, such as north
A window that faces south in the northern hemisphere or a window that faces north in the southern hemisphere.
Series connections increase what?
Voltage
Current
Cold
Heat
A dc-to-dc converter is often called?
Microinverter
Interactive converter
Optimizer
Pessimizer
What is PVUSA test conditions temperature?
25C cell temperature
20C cell temperature
25C ambient temperature
20C ambient temperature
Which of the following is used to calculate maximum system voltage?
Current
Power
Temperature
Irradiance
A PV system that would produce 7kWac under STC conditions, which is not clipping power, is installed in a location with an average of 6PSH (peak sun hours, aka kWh/square meter per day average) would produce how much energy in one year?
14,008 kWh
1,503 kWh
3,307 kWh
15,330 kWh
Which of the following will have the highest voltage setting for charging flooded lead-acid batteries?
Bulk charge
Absorption charge
Float charge
Equalization charge
Which of these would you be most likely to find on a module spec sheet?
Temperature coefficient
Maximum string size
Output frequency
Voltage drop from module to inverter
When working on a lead-acid battery bank with a hydrometer, what is the most important personal protective equipment?
Fall protection
Apron
Eye protection
Equalizer
