Q25. A grounding electrode is required at the location of all ground-mounted and pole-mounted PV arrays. Which typeof grounding electrode is NOT permitted for arrays. Which type of the grounding electrode is NOT permitted for array grounding?

Q26. A AWG THWN-2 PV output conductors from two PV arrays are run in the same 3 in, conduit to their respective functionally grounded inverters in the building. The three PV source circuits are each protected by a
15A fuse in the combiner box at the array. The conduit, which is strapped directly to the roof,is exposed to design temperatures of 140′ F (60’C) during its 30 ft.
Exposed run. What is the MAXIMUM current carrying capability value of the PV output conductors?

Q27. An installer has decided to use 31 in. long. 3.1/2 in diameter conical ground screws as the footings for a
3.840W solar electric system. Access to he is too difficult to pour concrete footings. The soll is classified as sandy loam. The design wind speed is 90 mph with an uplift force of 32 ibs/ft2. What is the MINIMUM number of screw required to resist uplift loads?

Q28. A PV array with 58 in. X 38 in modules in portrait orientation is to be mounted at a 35 tiit angle on a shingle roof that has a 5:12 pitch. Assuming the support leg is attached to the top of the modules and is perpendicular to its face, what is the length of the support leg for the modules?

Q29. A grid-connected PV system on a dwelling is producing 30% less power than expected. The conductors from threes strings of modules enter into a 3-pole fused dc disconnect, and each ungrounded conductor is connected to a separate pole. On the inverter side of the switch terminals, the three strings are combined. The dc disconnect switch is opened. The voltages on the array side of theswitchare 440 on string #1, 444V on string
#2, and 0V on string #3. The dc disconnect is then closed and the inverter resumes operating, still producing about 30% less power than expected. A clamp-on ammeter is used to measure the dc current of each string of each string of modules where they enter the rooftop junction box. The operating currents of each string are
3.9A for string #1, 3 85A for string #2, and 4.3 A for string #3. What is the MOST likely with the system?

Q30. A tap conduct is to be connected to a feeder supplied by both a utility service source and a utility-interactive inverter source. The feeder utility source is a 400A breaker in a service panel, the inverter overcurrent protection device is rated at 100A, and the inverter continuous output current is 72. The tap conductor that is to be installed will be 17 ft. long. It will be located in a raceway and will supply a subpanel with a 50A main breaker.
What is the MINIMUM required ampacity of the tap conductor?

Q31. Which of the following should a PV installer do during dc insulation resistance testing?

Q32. A commercial 600v carport-mounted PV system is installed with rigid running under the parking lot to an inverter pad located at the edge of the parking lot. At what depth below the parkinglot base MUST condult be buried?

Q33. Which of the following MUST be referenced for determining a site’s design wind speed?

Q34. When running horizontal 1-1/4 in, electrical metallic tubing (EMT) with compression fittings, what is the MAXIMUM permissible distance between condult supports?

Q35. A ground-mounted PV system operating with an open-critical voltage of 550V is in a public park. Which installation procedure will meet NEC requirements for protecting the public from potential electric shock?

Q36. Which of the following voltages should be included on the dc disconnected label to indicate MAXIMUM system voltage?

Q37. An 8KWsc roof-mounted array is placed on a school building. The inverter is located within 1 ft, of the array boundary and has an integrated ac-and dc-disconnecting switch. The system is to be connected to a 400A load center, protected by a 400A main breaker. Which of the following MUST be included to meet NEC requirements?

Q38. A metal condult containing an array circuit with Vmo of 400Vdc is connected to a metal enclosure at the location where the concentric knockouts have been punched by the manufacturer. Which method of attachment should be used?

Q39. When installing an ungrounded PV system with an open-circuit voltage of 450Vdc and a maximum voltage of
3000Vdc which procedures should be followed to establish an electrically safe condition?

Q40. A PV system installation utilizes micro inverters connected to each module of the array. Each micro inverter has a nominal rated output of 250WV. Single phase. The microinverters are listed so that multiple inverters may be connected in parallel to a single feeder circuit, and each inverter has ancable and connector rated for
30A. What is the MAXIMUM number of inverters that may be wired together on a single 30A feeder circuit?

Q41. An installer was asked to provide a means to measure the voltage of each battery in a system. The bank is located 50 ft.
From the data logger. The installer will be using shielded. Twisted pairs of instrumentation wiring, all run in the bundle a conduct.
The signals are connected to isolated and ungrounded inputs at a data logger. Which safely precaution is MOST needed to protect the instrumentation wiring?

Q42. A PV system equipped with rapid shutdown requires a label stating ”RAPID SHUTDOWN SWITCH FOR SOLAR PV SYSTEM”.
Which is the BEST description of where this label is required?

Q43. How should stratification be eliminated in a set of large, stationary, stationary flooded lead-acid batteries?