Test Questions Flashcards
A stand alone inverter is sized based on the size of what?
The loAds to which it must supply power.
What is the primary purpose of a charge controller aka PV controller ?
To protect the batteries from over charge and over discharged.
An interactive inverter is sized based on what?
The output of the array.
Voltage drop is primarily dependent on what?
Length of gauge of conduit.
The monitoring system on the inverter of a roof top interactive pv system is reporting low levels of irradiance and low system current. What is most likely the cause?
It’s cloudy the systems fine.
The intentional controlled over charge of batteries, which causes gassing helps to ensure that each cell is brought up to a full charge is. A
Equalization charging.
fall protection minimum for osha?
6ft.
A ground fault has been indicated in a grid tied inverter what should the technician do first?
Turn off the dc and ac disconnects
Bypass diodes are commonly located in which system component?
Modules
The amount of irradiance required to test pv cells and modules at NOCT iOS
Nominal operational cell temperature.
800w/m 2
The standard for which pv modules in the United starte are tested and certified is what?
UL 1703
Where should the dc disconnect go after you install a micro inverter?
No dc disconnect is used in a micro inverter.
The ampacity my of a conductor is affected most by which of the following
Temperature.
The authority having jurisdiction ahj has the primary responsibility of?
Making sure everything is up to compliance.
What function does a maximum power point tracker perform
Optimize power output of the array due to variable irradiance and temperature levels.
Device commonly used in a pv system whose function is to change the voltage and waveform of electrical energy.
Inverter.
What parameter on a pv module curve is used to calculate the minimum number of modules to be configured in a series of strings.
Vmp
The grounding electrode conductor of a pv system should be what color .
Green
The rooftop mounting system transfers the weight of the pv system and its associated wind, snow and seimisic loads to the roof trusses or rafters they which components
The structural attachments
What is the correct sequence of energy flow of the utility grid system.
Generation
Transmission
Distribution
Service
Bypass diodes are commonly located in which system component
Modules
Power is to energy as irradiance is to what?
Irradiation
Can high voltage trip a circuit breaker
Not typically
Solar and wind grid system
Hybrid
Irradiance proportionally affects ?
Photovoltaic amperage
What is the reason for grounding Pv system
Allow surges to dissipate properly.
Which component in a off grid system is directly related to the autonomy of the system.
Battery Bank
What type of grounding must be present in a roof mounted pv system less than 50 v or nominal voltage?
Equipment grounding
You just installed a pv array using micro inverter system . Where should the dc disconnect be located?
No dc disconnect is used in a micro inverter.
A circuit where electricity can flow in a complete circle from the electrical source (such as the utility company a battery, etc) to the load , and back again to the source. See also open circuit)
Closed circuit.
Power is to energy as irradiance is to what?
Irradiation
The hydraulic equivalent of voltage
Pressure
During a ground fault condition where the metallic equipment becomes energized, what protects against electrical shock?
Equipment grounding conductor or
E.G.C
The angle between the horizontal direction of the sun and a reference angle (usually north).
Azimuth Angle ( a typical angle for photovoltaic module would be 180 degrees )
Which oven system has the fewest number of components and is most efficient?
Direct coupled system.
Optimizer power output of the array due to variable irradiance and temperature levels is called what?
Maximum power point tracker
The amount of solar radiation coming from a circle in the sky centered on the sun disk and having a radius of between 2.5 and 3.5 degrees depending on the type of instrument used, is called what?
Circus solar radiation
What is the standard test conditions for irradiance called?
1000 w/m squared
The measure of the quantity of the electricity flowing in a circuit.
Amp
A standardized system of measurement for the size of electrical wire and demoted by awg associated with a number indicating the wire size. The smaller the wire the higher the number. What is this measurement system called?
American wire gauge or awg
What parameter on a Pv module do you use to calculate the minimum number of mods on a string.
VMP
What room should you never install a dc disconnect?
Bathroom- because it gets wet
The hydraulic equivalent of current is what?
Flow
What is the name of the special silicon that modules are commonly made out of ?
Amorphous Photovoltaic
What is the primary purpose of a diode
To decrease the negative effects of shading.
Describe a transformer.
A step up or down ac voltage.
What three parameters are typically listed on an interactive inverter spec sheet?
Input voltage
Output voltage
Continues power ratings
What component of an off grid pv system is typically located between the pv array and battery bank?
Charge controller
What is the primary power source for a grid tied inverter?
PV Array
Power is to energy as irradiance is to what?
Irradiation
The hydraulic equivalent of voltage
Pressure
During a ground fault condition where the metallic equipment becomes energized, what protects against electrical shock?
Equipment grounding conductor or
E.G.C
Power is to energy as irradiance is to what?
Irradiation
The hydraulic equivalent of voltage
Pressure
During a ground fault condition where the metallic equipment becomes energized, what protects against electrical shock?
Equipment grounding conductor or
E.G.C
Power is to energy as irradiance is to what?
Irradiation
The hydraulic equivalent of voltage
Pressure
During a ground fault condition where the metallic equipment becomes energized, what protects against electrical shock?
Equipment grounding conductor or
E.G.C
Angle at which a photovoltaic array is tilted from the horizontal. An array tilt angle of 90 degrees indicates modules that are vertical with and perpendicular to the earth regardless of the direction the module faces
Array tilt angle
Two or more photovoltaic modules connected together is callled what
Array
Ahj has the primary responsibility of you
Make the determination that system meets code compliance.
What time of year during solar noon will an object cast the longest shadow in the northern hemisphere.
December 21, winter solstice. (Because it’s moved to the equator)
Interactive inverters used for grid tied applications usually contain what?
Ground Fault Protection Device
What is the most significant outcome of a solar Pv system operating in an environment that is much warmer than standard test conditions.
Power would decrease.
What type of PV array mounting system is commonly used on commercial flat roofs in order to avoid penetrating into the roof surface.
Ballasted amount System.
What crystalline silicon manufacturing process uses a single crystalline seed dipped repeatedly in a vat of Molten silicone that is slowly rotated
Mono crystalline silicon.
A specialized form of c/b switch designed to automatically protect an electrical circuit from damage caused from overloads or shorts by opening the circuit and interrupting the flow of current.
Circuit breaker
Solar radiation that reflected from the ground, ground cover and bodies of water on the surface of the earth is called what?
Albedo
The farther north you are the better it is to?
Increase the photovoltaic module tilt angle.
