CSLB C-46 Solar (Trade Exam) — All Questions

According to NREL, what do cell-level hot spots generally do to module performance?

• a.They do not significantly affect it✓
• b.They always trip the ground-fault detector
• c.They raise the open-circuit voltage
• d.They cut the string's output in half

NREL says cell-level hot spots generally will not significantly affect module performance, although a hot connection is a fire risk to correct. A single hot cell does not halve a string's output. A hot cell is not a ground fault. Heat lowers voltage rather than raising it.NREL Best Practices for O&M of PV and ESS

A system's model predicts 820 kWh for May, but the meter shows 700 kWh. About how large is the shortfall?

• a.About 15 percent✓
• b.About 17 percent
• c.About 8 percent
• d.About 120 percent

The shortfall is (820 - 700) divided by 820, or about 14.6 percent. 8 percent understates the gap. 120 is the number of kWh, not a percentage. 17 percent divides by 700, the wrong base.NREL Best Practices for O&M of PV and ESS

Which annual tests does NREL's sample service schedule include for a PV array?

• a.Utility meter calibration at the service
• b.String-level Voc and DC operating current✓
• c.Module serial number audits by the crew
• d.Roof framing moisture content readings

The sample schedule includes annual string-level open-circuit voltage and DC operating current tests. Framing moisture is a building matter. Serial audits do not test performance. Meter calibration is the utility's job.NREL Best Practices for O&M of PV and ESS

On a hot afternoon every string reads low in voltage together. What is the likely cause?

• a.A loose neutral
• b.High cell temperature✓
• c.A blown string fuse
• d.A single failed bypass diode

Higher temperature causes a much larger decrease in voltage, and it affects every string alike. A failed diode affects one module or string. A blown fuse affects one string's current. A loose neutral is an AC problem.DOE, Solar Photovoltaic Performance and Efficiency Basics

What does DOE say to check about valves on a solar water heating system?

• a.That the valves are lubricated weekly
• b.That the valves are closed for the winter
• c.That the valves are removed in summer
• d.That valves are in their proper positions✓

DOE's inspection list says to check that all valves are in the proper operating position. Closed valves would stop circulation. Removing valves is not a maintenance step. A weekly lubrication schedule is not DOE's advice.DOE Energy Saver, Solar Water Heating System Maintenance and Repair

On a solar water heater, where should an inspector look for fluid leaks?

• a.At the roof ridge
• b.At the collector glass cover
• c.At the storage tank lid or cap
• d.At every pipe connection✓

DOE says to look for fluid leaks at pipe connections. The glass is not where fluid joins. The tank lid is not a plumbing joint. The ridge has no pipe connections.DOE Energy Saver, Solar Water Heating System Maintenance and Repair

What does DOE say to look for on pipes, ducts and wiring?

• a.Excess lubricant on the fittings
• b.Extra supports under each pipe
• c.Insulation damage or degradation✓
• d.Fresh paint on the pipe covers

DOE says to look for damage or degradation of insulation covering pipes, ducts and wiring. Paint is not a performance concern. Lubricant has no role on insulation. More supports are not part of the check.DOE Energy Saver, Solar Water Heating System Maintenance and Repair

What does DOE say to check about the hardware that attaches collectors to their supports?

• a.That the bolts are painted
• b.That the bolts are loosened for expansion
• c.That the nuts are replaced yearly
• d.That all fasteners are tight✓

DOE says to check all nuts and bolts attaching collectors to support structures for tightness. Paint does not secure a collector. Yearly replacement of every nut is not DOE's advice. Loosened bolts would let the collector shift.DOE Energy Saver, Solar Water Heating System Maintenance and Repair

What does DOE say to look for in collector glazing?

• a.Tree sap on the aluminum frame
• b.Fingerprints from the installer's gloves
• c.Dew on the underside of the glass
• d.Cracks, and whether the seals are good✓

DOE says to look for cracks in the glazing and check that the seals are in good condition. Fingerprints do not affect performance. Sap on the frame is not the glazing inspection. Dew alone does not say whether the seals are good.DOE Energy Saver, Solar Water Heating System Maintenance and Repair

According to DOE, systems with electrical components usually need what after about 10 years?

• a.A complete replacement of the tank
• b.Nothing at all
• c.A replacement part or two✓
• d.A new roof

DOE says systems with electrical components usually require a replacement part or two after 10 years. DOE does not say the whole tank must be replaced. Electrical parts wear and eventually need replacing. A new roof is unrelated.DOE Energy Saver, Solar Water Heaters

Why may collector glazing need cleaning in dry climates, according to DOE?

• a.Dry air makes the glass brittle
• b.No natural rainwater rinse✓
• c.Sunlight bakes dirt onto the frame
• d.Dust is magnetic and clings to glass

DOE says glazing may need cleaning in dry climates where rainwater does not provide a natural rinse. Dry air does not make glass brittle. Dust is not magnetic. Frame baking is not the stated reason.DOE Energy Saver, Solar Water Heaters

After an inverter is replaced, what must still work with the equipment that remains?

• a.The previous monitoring portal login
• b.The former AC disconnect label
• c.The rapid shutdown function✓
• d.The old inverter's warranty

Equipment performing rapid shutdown must be listed for it, so the function must still work after the replacement. The warranty belongs to the removed unit and is not an operating function. A portal login is a convenience, not a safety function. A label does not perform a shutdown function.City of Berkeley 2022-code checklist (CEC 690.12)

What must a repair or alteration to an existing PV system not do?

• a.Require a new utility meter at the service
• b.Make existing equipment lose its listing✓
• c.Take more than a day of labor on the roof
• d.Change the module color from the original

Berkeley's checklist says alterations or additions must not cause existing equipment or components to lose their listings. Color has nothing to do with listing. Duration is not part of the rule. A new meter is not part of the rule.City of Berkeley 2022-code checklist

Under the Fire Code's general ESS provisions, how is a repair that uses non-identical parts treated?

• a.As a retrofit of the ESS equipment✓
• b.As a brand-new ESS installation
• c.As routine maintenance of the unit
• d.As a cosmetic change to the unit

The Fire Code treats repairs with other than identical parts as retrofitting. Identical-part repairs are the routine maintenance. Replacement of the whole ESS is what counts as a new installation. Non-identical parts change the equipment, so it is not cosmetic.2022 CFC 1207 (County of Lake excerpt)

Who may repair an energy storage system under the Fire Code's general provisions?

• a.Qualified personnel only✓
• b.A helper under verbal instruction
• c.The homeowner with the manual
• d.The utility's lineworkers

The Fire Code says repairs of ESS shall only be done by qualified personnel. Owner repairs are not authorized by the manual. Verbal instruction does not make someone qualified. The rule is about qualification, not employer, so lineworkers are not the only ones.2022 CFC 1207 (County of Lake excerpt)

What must be left with the owner of a residential energy storage system?

• a.The utility's current rate schedule and all of its tariff sheets
• b.The crew's signed time sheets and daily job logs for the week
• c.A copy of the roofing contractor's workmanship warranty
• d.The manufacturer's installation and operation instructions✓

The code calls for a copy of the manufacturer's instructions and a label with the contact information of qualified service providers. Rate schedules are not part of the ESS documents. The roofing warranty is unrelated. Time sheets are internal business records.2022 CRC R328 (County of Lake excerpt)

When damaged module mounts are replaced, what governs how they are attached?

• a.Only the manufacturer's specifications✓
• b.The installer's usual practice on similar roofs
• c.Whatever fastener happens to be on the truck
• d.The roofer's preference

Module attachments must be in accordance with the manufacturer's specifications. A fastener on hand may not meet the specification. Habit is not a specification. The roofer's preference does not set structural attachment.City of Berkeley 2022-code checklist

A repair requires re-terminating a lug. What torque should be used?

• a.As tight as the wrench will allow it
• b.The manufacturer's recommended torque✓
• c.Snug by hand, then a quarter turn more
• d.Whatever value suits copper wire

Pressure terminals must be tightened to the manufacturer's recommended torque. Hand tight can leave a loose, heating connection. Over-tightening can damage the lug or conductor. The conductor material does not remove the torque specification.Solar Permitting Guidebook (OPR) inspection checklist

Berkeley's checklist requires PV equipment, wiring and interconnections to be installed by whom?

• a.The homeowner, using the manual
• b.A helper assigned to the crew
• c.The electric utility's own crew
• d.A qualified person per NFPA 70E✓

The checklist calls for installation by a qualified person trained per NFPA 70E 2018, which also applies when repairing or replacing. A helper without training is not qualified. The homeowner is not assumed qualified. The utility does not do the installer's work.City of Berkeley 2022-code checklist

When replacement modules are installed, what does the Guidebook's inspection list want to match the permit plan?

• a.The installer's shirt color and logo
• b.Module model, quantity and location✓
• c.The truck's license plate number
• d.The module color and finish

The inspection list checks that modules match the plan in model, quantity and location. Color is not what the list checks. Crew clothing is not an inspection item. The truck plate is not an inspection item.Solar Permitting Guidebook (OPR) inspection checklist

What must DC breakers used in a PV system be?

• a.Rated for use in a household refrigerator circuit
• b.Any ordinary AC breaker of the right size
• c.Unlisted when under 20 amps
• d.Listed and rated for use with PV systems✓

San Diego County's checklist says DC breakers shall be listed and rated for PV use, which also governs replacements. An AC-only breaker may not interrupt a DC arc. A refrigerator rating has no bearing on DC PV use. Small size does not remove the listing requirement.County of San Diego PDS 081S (2025 codes)

After an ESS repair, what must the unit carry for the owner's benefit?

• a.No label on the unit
• b.A sticker saying the unit cannot be serviced by anyone
• c.A label with the crew's home addresses and phone numbers
• d.A label with qualified service provider contacts✓

The code calls for a label containing the contact information for the qualified maintenance and service providers. Home addresses are not the required information. The unit can be serviced by qualified providers. The code does call for a label.2022 CRC R328 (County of Lake excerpt)

When exposed energized parts must be worked, what must be in place for protection where needed?

• a.A second inverter on standby nearby
• b.Suitable barricades, tags or signs✓
• c.A spare set of fuses in the truck
• d.The neighbor's written permission slip

Cal/OSHA calls for suitable barricades, tags or signs where needed for protection. A second inverter does not protect anyone. Spare fuses do not warn or block access. A neighbor's permission is irrelevant.Cal/OSHA Title 8 section 2320.2

Which rule protects utility lineworkers from backfeed from a customer's generation?

• a.Only the utility's lineworkers may ever touch inverters
• b.Positive means to prevent backfeed✓
• c.A warning sign at the meter is enough by itself
• d.Backfeed is allowed for systems under 10 kW when labeled

Section 2320.9 bars connecting a power source to premises wiring unless positive means prevent transmission beyond it, unless the utility authorized the interconnection. A sign does not physically prevent backfeed. The rule has no 10 kW exemption. Installers may work on inverters; the rule concerns preventing backfeed.Cal/OSHA Title 8 section 2320.9

After rapid shutdown has been initiated, what should a firefighter assume about the array?

• a.That the conductors are safe to cut with insulated tools
• b.That the array can still be energized in sunlight✓
• c.That it has been brought down to zero volts
• d.That it is isolated from the sun by the shutdown

Rapid shutdown lowers the voltage to set limits; it does not make the array dead while light falls on it. Zero volts is not what rapid shutdown delivers. Modules keep producing voltage whenever light reaches them. Cutting energized conductors is dangerous.DOE-hosted fire service presentation; CEC 690.12

How far must an outdoor residential ESS on an exterior wall be from doors and windows directly entering the dwelling?

• a.Not less than 10 feet
• b.Not less than 3 feet✓
• c.Not less than 5 feet
• d.Not less than 1 foot

The 2022 CRC allows outdoor and exterior-wall locations not less than 3 feet from doors and windows directly entering the dwelling. 1 foot is closer than allowed. 5 feet is farther than the minimum. 10 feet is farther than the minimum.2022 CRC R328 (County of Lake excerpt)

What is the purpose of the roof pathways and ridge setbacks required around a rooftop PV array?

• a.To improve the array's appearance from the street
• b.To leave room for future expansion modules
• c.To let firefighters walk and ventilate✓
• d.To reduce the array's wind load on the roof

Firefighters must be able to walk to the ridge and ventilate a burning house, and the pathways and setbacks provide that access. Pathways are not planned expansion space. Wind load is addressed by structural design, not by pathways. Appearance is not the purpose of the fire access rules.2022 CRC R324.6 (City of Berkeley checklist)

On a construction site, who may be required or knowingly permitted to work in an unsafe place, and for what purpose?

• a.A worker, to save the cost of a ladder
• b.A worker, to finish the day's schedule
• c.A worker, to meet a customer's deadline
• d.A worker, only to make it safe✓

Section 1511 says no worker shall be required or knowingly permitted to work in an unsafe place unless for the purpose of making it safe. A schedule is not a reason to accept an unsafe place. A deadline does not justify exposure to a hazard. Saving a ladder's cost is not an exception.Cal/OSHA Title 8 section 1511

What marking must a cover over a roof opening carry?

• a.Opening--Do Not Remove✓
• b.Danger--High Voltage
• c.Caution--Wet Paint
• d.Fragile--Handle With Care

Section 1632 requires covers to be secured against displacement and marked Opening--Do Not Remove. Wet Paint has nothing to do with an opening. High Voltage does not describe a cover over a hole. Fragile does not warn people away from removing it.Cal/OSHA Title 8 section 1632

An ESS with an integrated shutdown button is installed indoors. What else does San Diego County's checklist say is needed?

• a.A second button next to the first
• b.A sign on the garage door
• c.Nothing; the button satisfies every rule
• d.A separate outdoor disconnect✓

An integrated shutdown button can satisfy 706.15, but if the ESS is installed indoors a separate outdoor disconnect is needed. The button alone does not give responders an outdoor means of shutdown. A second button indoors adds nothing outside. A sign does not disconnect anything.County of San Diego PDS 081S (2025 codes)

Under Section 1730, other roofing operations call for fall protection on roofs of what height?

• a.More than 6 feet
• b.More than 20 feet✓
• c.More than 10 feet
• d.More than 7 1/2 feet

Section 1730 protects against falls from roofs of a height of more than 20 feet for other roofing operations. 7 1/2 feet is the general trigger in Section 1670. 6 feet is the residential roofing trigger in Section 1731. 10 feet is not the trigger height in Section 1730.Cal/OSHA Title 8 section 1730

A lanyard allows a 6-foot free fall, and the system limits deceleration to 3.5 feet. How much clear space is needed below the anchorage before adding the worker's height?

• a.9.5 feet✓
• b.21 feet
• c.6 feet
• d.3.5 feet

The free fall and the deceleration distance add: 6 + 3.5 = 9.5 feet. 6 feet counts only the free fall. 3.5 feet counts only the deceleration. 21 feet multiplies the two figures.Cal/OSHA Title 8 section 1670(b)

How must a fall restraint system be rigged?

• a.To allow free movement over the whole roof
• b.To permit reaching the edge when tied to a guardrail
• c.To limit movement to the sides of the work area✓
• d.To allow a 6-foot free fall and a stop

Section 1670 says restraint is rigged to allow movement only as far as the sides of the working level or area. A 6-foot free fall describes arrest, not restraint. Guardrails are not anchorages. Free movement over the whole roof would let the worker reach the edge.Cal/OSHA Title 8 section 1670

To what must roof safety lines be attached under Section 1724?

• a.Substantial roof anchorages✓
• b.Plumbing vents poking through the roof
• c.Antennas and chimney flue pipes
• d.The ladder used to reach the roof

Section 1724 calls for safety lines attached in a secure manner to substantial anchorages on the roof. A vent pipe is not a substantial anchorage. An antenna or flue can fail under load. A ladder can slide or tip.Cal/OSHA Title 8 section 1724

What does Section 3276 prohibit regarding a ladder?

• a.Setting it at the one-quarter angle
• b.Moving or extending it while occupied✓
• c.Climbing it while facing the rungs
• d.Placing it on firm, level ground

Ladders are not moved or extended while occupied. Level ground is the proper place for a ladder. The one-quarter angle is the recommended setup. Facing the ladder is the required way to climb.Cal/OSHA Title 8 section 3276

Which is an accepted way to observe employees under the high-heat procedures?

• a.A sign posted at the yard
• b.An annual survey
• c.A mandatory buddy system✓
• d.A weekly e-mail

The high-heat procedures include observation by a supervisor or designee of 20 or fewer employees, or a mandatory buddy system. A yearly survey does not observe anyone on the job. A sign does not observe employees. A weekly message does not observe anyone.Cal/OSHA Title 8 section 3395

How must the employer's workplace assessment for personal protective equipment be certified?

• a.By a vote of the crew
• b.By the supplier's catalog
• c.Orally
• d.In writing✓

Section 3380 requires the hazard assessment to be certified in writing. Oral certification leaves no record. A catalog does not certify the employer's assessment. A vote is not a hazard assessment.Cal/OSHA Title 8 section 3380

What does Section 3380 say about defective or damaged personal protective equipment?

• a.It shall never be used✓
• b.It may be used on short jobs
• c.It may be used after monthly inspection
• d.It may be used once taped

Defective or damaged personal protective equipment shall not be used. Taping does not restore protection. Job length does not change the rule. Monthly inspection does not permit using defective equipment.Cal/OSHA Title 8 section 3380

What must a construction employer keep in writing for medical emergencies?

• a.A plan to provide emergency medical services✓
• b.A copy of each owner's mortgage and loan papers
• c.A map of nearby parks
• d.A list of the employees' favorite restaurants

Section 1512 requires a written plan to provide emergency medical services. Restaurants are irrelevant to emergencies. A mortgage has nothing to do with it. Park maps do not help in an emergency.Cal/OSHA Title 8 section 1512

What procedure must a written IIPP include for workplace injuries?

• a.A procedure to waive written reports for minor injuries at work
• b.A procedure to investigate occupational injury or illness✓
• c.A procedure to keep injuries secret from the employer and insurer
• d.A procedure to send the employee home unpaid

Section 3203 requires a procedure to investigate occupational injury or occupational illness. Sending an injured worker home unpaid is not a required procedure. Injuries cannot be hidden from the employer. Reports are not waived by size of injury.Cal/OSHA Title 8 section 3203

What does Section 3203 require for methods of correcting unsafe conditions?

• a.Correction in a timely manner by severity✓
• b.Correction only after an injury
• c.Correction at the end of the project
• d.Correction when a customer complains

The IIPP must include methods of correcting unsafe conditions in a timely manner based on the severity of the hazard. Waiting for an injury defeats prevention. Waiting for the project end leaves workers exposed. Customer complaints are not the trigger.Cal/OSHA Title 8 section 3203

Workers exposed to known hazards such as flammable liquids, caustics or toxic materials must be instructed in what?

• a.The cost of the material per container
• b.Hazard recognition, self-protection and first aid✓
• c.Only how to dispose of the empty container safely
• d.The supplier's warranty and return terms

Section 1510 requires instruction in recognition of the hazard, procedures for protection and first aid in case of injury. Cost does not protect anyone. Disposal alone leaves out safe use and first aid. Warranty terms are not safety instruction.Cal/OSHA Title 8 section 1510

What must a contractor hold to remove hazardous substances from a site?

• a.A signed letter of consent from the property owner or tenant
• b.A training card from the module manufacturer
• c.Only a C-46 license plus a general liability policy on file
• d.A hazardous substance removal certification from CSLB✓

CSLB says contractors who do hazardous substance removal work must be certified by CSLB. A C-46 license does not carry that authority. A manufacturer card is not a state certification. Owner permission cannot substitute for certification.CSLB, Before You Apply (hazardous substance removal certification)

What does the Hazard Communication standard require of all employers?

• a.To keep chemical information away from customers
• b.To inform employees about their chemical exposures✓
• c.To buy unlabeled chemicals from any vendor
• d.To store chemicals at the contractor's home office

The standard requires employers to give employees information about the hazardous chemicals to which they may be exposed. Labels are required, not avoided. The duty is to employees, and it is not about hiding information. Chemicals on a job must be where the work is, with information at hand.Cal/OSHA Title 8 section 5194

Which asbestos examination must a new CSLB license applicant complete if it has not been done before?

• a.A hazardous substance field test
• b.No asbestos examination is required
• c.A closed-book abatement examination
• d.The asbestos open-book examination✓

CSLB requires all new applicants to complete the asbestos open-book examination if it has not been done previously, and it does not certify anyone for asbestos work. A hazardous substance field test is not part of the application. The required exam is open-book, not closed-book. Saying none is required contradicts CSLB's page.CSLB, Asbestos Open Book Examination

Besides high short-circuit current, which hazards does Sandia list for storage batteries?

• a.Noise above 85 decibels
• b.Ultraviolet exposure and radio interference
• c.Acid or caustic electrolyte, and shock✓
• d.Radioactive decay

Sandia lists high short-circuit current, acid or caustic electrolyte, and shock hazards for batteries. Batteries do not emit ultraviolet or radio interference as a hazard. Noise is not a battery hazard. Batteries are not radioactive.Sandia, PV Power Systems and the NEC: Suggested Practices

What does Sandia say hydrogen from battery charging poses if it is confined and not properly vented?

• a.A corrosion-proofing benefit
• b.A visual nuisance
• c.No hazard at any concentration
• d.An explosive hazard✓

Sandia says this gas, if confined and not properly vented, poses an explosive hazard. Hydrogen is a safety hazard, not just a nuisance. Hydrogen is not a protective coating. Hydrogen can ignite at ordinary concentrations in a closed space.Sandia, PV Power Systems and the NEC: Suggested Practices

According to DOE, who should service pressurized glycol loops?

• a.A homeowner with a pipe wrench at hand
• b.A qualified solar heating professional✓
• c.The nearest hardware store's clerk on duty
• d.A neighborhood pool cleaning service

DOE says pressurized glycol systems should be serviced only by a qualified solar heating professional. A homeowner risks injury and fluid loss. A pool service is not trained on solar loops. A store clerk is not a service provider.DOE Energy Saver, Solar Water Heaters

Why must ethylene glycol not be used in a solar water heating loop?

• a.It is toxic✓
• b.It is too thin to pump
• c.It costs more than water
• d.It freezes at a higher temperature

DOE says ethylene glycol must not be used due to toxicity, so non-toxic propylene glycol is used. Cost is not the stated reason. Its freeze protection is not the problem. Viscosity is not the stated reason.DOE Energy Saver, Solar Water Heaters

What does Section 1510 require for new workers regarding hazards?

• a.A copy of the company's payroll records
• b.A guided tour of the contractor's office
• c.Hazard and precaution instructions for the work✓
• d.A sales brochure for the products in use

New workers must be given instructions on the hazards and safety precautions applicable to the type of work in question. Payroll records are not safety instruction. A tour of the office does not cover site hazards. A brochure is not safety instruction.Cal/OSHA Title 8 section 1510