PAPER 2026 QUESTIONS WITH
ANSWERS GRADED A+
◍ Voc =.
Answer: OPEN CIRCUIT VOLTAGE
◍ NABCEP.
Answer: North American Board of Certified Energy Practioners
◍ JTA.
Answer: Job Task AnalysisThe JTA outlines the expected duties of a
qualified PV installation professional.
◍ ISC =.
Answer: SHORT CIRCUIT CURRENT
◍ Conduit Fill(i.e. Maximum Percent of Conduit Area Available for
Conductors).
Answer: NEC Chapter 9 Table 1
◍ Vmp =.
Answer: MAXIMUM POWER VOLTAGE
◍ Imp =.
Answer: MAXIMUM POWER CURRENT
◍ The inverter size is based upon the.
Answer: size of the PV array
◍ Voltage Drop Limits.
Answer: ASHRAE 90.1 Standards suggests no more than 3% of nominal
voltage.NEC suggests no more than 5% in an "Informational
Note".Sunpower standard is no more than 1%.
,◍ anti - islanding.
Answer: the inverter cannot operate alone as an island of power. The grid
tied PV system have to be able to disconnect from the grid whenever the
grid is down or not within specifications.
◍ Voltage Drop Equation.
Answer: % drop =(0.2 x D x I x R )/VWhere:D= one-way distance (in feet)I
= current (nominal actual value, no 125% factors, use Imp for solar
circuits)R = resistance of conductors (in ohms/1000ft)V = voltage (typical,
nominal, use Vmp for solar circuits)Resistance values can be found in NEC
Chapter 9 Table 8 "Conductor Properties"
◍ Main components of a DC coupled system, the most common and simple off
grid systems..
Answer: Solar modules, charge controller, battery, inverter
◍ Battery inverters.
Answer: Create voltage
◍ What size FMC conduit should be used for four size 6 AWG XHHW
conductors, one size 8 AWG XHHW EGC and four 10 AWG THHN
conductors? Only use the NEC code book to answer this question..
Answer: 1-1/4"Use Chapter 9 Tables 4 and 5.
◍ Grid Tied Inverters.
Answer: Work when there is no utility
◍ Main components of an AC coupled system, complicated and less common
system.
Answer: solar modules, grid tied inverter, off grid inverter/charger, batteries
◍ Grid Tied Battery- Backup (GTBB) PV systems can.
Answer: operate as grid tied systems and off grid systems
◍ What are loads?.
Answer: Devices that consume electricity
◍ BIPV.
, Answer: Building-Integrated Photovoltaics
◍ Direct, Direct Coupled PV System.
Answer: The simplest type of PV system, the only components are PV and
the load.
◍ A self regulating PV system.
Answer: is a stand alone PV system without a charge controller, designed so
that it will not charge over 3% battery capacity in an hour
◍ Can single phase inverters be connected to 3-phase power systems?.
Answer: Yes, as long as significant unbalanced voltages cannot
result705.100
◍ Building Integrated PV or BIPV.
Answer: a part of the building and is not as efficient as regular PV because it
is hotter
◍ Solar grid parity.
Answer: when energy produced by PV is less expensive than electricity
produced by conventional means
◍ Ampacity.
Answer: The ability of a wire to carry current
◍ What is the minimum busbar rating for a subpanel used as an inverter ac
combiner panel to combine three 4000W, 240V single phase inverters?.
Answer: 125ARating of each breaker = 16.7 X 1.25 = 25ASum of inverter
breakers = 3 x 25A = 75AMinimum size of back-fed breaker in main service
panel = 3 x 16.7A x 1.25 = 62.2 --> 70AMinimum size busbars in subpanel
x 1.2 = inverter breakers + utility breaker = 75A + 70AMinimum size
busbars in subpanel = (75A + 70A)/1.2 = 121 --> 125A705.12(D)(2)
◍ Can an inverter output be connected to a subpanel instead of the main
distribution panel?.
Answer: Yes, see 705.12(D).But be careful that each panel in series meets
the minimum busbar size requirements.