Deficiency Identification, Documentation Package, and Project Defense

Deficiency Identification, Documentation Package, and Project Defense

This capstone lab brings together every skill you have built across the program. You will inspect a real installation for code and safety violations, compile a complete permit package, and defend your own system design before a panel. Employers and inspectors will test you in exactly these three ways throughout your career.

Part 1 — Deficiency Identification

Before any installation is energized, it must pass inspection. Inspectors look for violations of the National Electrical Code (NEC) Article 690, OSHA standards, and manufacturer requirements. As an installer, you are responsible for catching problems before the inspector does — and before anyone gets hurt.

When you inspect the staged installation, work methodically from the array to the point of interconnection. Common categories of deficiency include:

• Grounding and bonding: Every metal enclosure, rack, and module frame must be bonded to the equipment-grounding conductor (EGC). A missing EGC creates a shock hazard if a ground fault occurs.
• Disconnecting means labeling: NEC 690 requires that each disconnect be durably and legibly marked with its purpose. An unlabeled disconnect prevents firefighters and first responders from safely de-energizing the system.
• Overcurrent protection device (OCPD) sizing: An oversized OCPD fails to protect conductors from overheating. Check that the OCPD ampere rating does not exceed the conductor's allowable ampacity after applying all applicable correction and adjustment factors.
• Wiring methods in wet or damp locations: Only listed wiring methods for wet locations — such as USE-2 or PV Wire for exposed outdoor runs — are permitted. Standard THHN is not rated for direct exposure to weather or UV.
• Rapid-shutdown compliance: NEC 690.12 requires a rapid-shutdown system for rooftop PV. The required label must appear at the service equipment or the rapid-shutdown initiator so responders can act quickly. A missing label is a cited violation.

Record every deficiency on a field-correction notice (FCN) form. Each entry must include: the location of the deficiency, a description of the problem, the specific NEC 690 article or OSHA standard that applies, and the corrective action required. Vague notes such as "wire is wrong" will not pass — cite the code.

Safety reminder: Treat the staged installation as live until the instructor confirms it is de-energized and locked out. Follow lockout/tagout (LOTO) procedures and wear appropriate PPE — safety glasses and insulating gloves — before touching any component. Never assume a system is off because it appears off.

Part 2 — The Permit Documentation Package

Authorities Having Jurisdiction (AHJs) — your local building and electrical departments — require a complete submittal before issuing a permit. An incomplete package causes delays and costs money. Your binder and digital folder must contain every required sheet in the order the AHJ expects.

Required documents:

1. Cover sheet — system summary (system size in kW-DC, inverter type, interconnection method, owner name, address, permit number if assigned)

2. Site plan — to-scale roof layout showing array location, setbacks, access pathways, and service equipment location

3. Single-line diagram (SLD) — NEC 690-compliant electrical schematic from modules to utility meter, showing all conductors, OCPDs, disconnects, labeling, and grounding

4. Equipment cut sheets — manufacturer specification sheets for modules, inverter(s), racking, and any rapid-shutdown device

5. String calculation worksheet — open-circuit voltage (Voc) temperature-corrected to the AHJ's record low, maximum power-point voltage (Vmp) calculations, and short-circuit current (Isc) adjustments

6. Load calculation — if the interconnection is a load-side tap, the 120% rule calculation (NEC 705.12) must be documented

7. Conduit fill worksheet — number and size of conductors verified against NEC Chapter 9, Table 1

8. Interconnection agreement checklist — confirmation that the utility has approved the interconnection method

9. AHJ inspection photo set — labeled photos taken during installation showing grounding connections, conduit runs, module labels, and rapid-shutdown equipment

10. Commissioning report — measured Voc per string, Isc per string, insulation resistance test results, and inverter startup confirmation

Review every sheet before submission. A panel evaluator will ask you to explain any page, so know your own package.

Part 3 — The Oral Defense

The oral defense is your opportunity to demonstrate that you understand why you made each decision, not just what you did. Structure your 15 minutes as follows:

• Design rationale (4 min): Explain site selection, shading analysis, system sizing, and equipment selection. Connect each choice to site conditions and client goals.
• Single-line diagram walk-through (6 min): Move from the array to the meter. At each point, name the component, state its function, and identify the code requirement it satisfies.
• Q&A and what-if scenario (3 min): Answer panel questions directly and honestly. If you do not know, say so and explain how you would find the answer.
• Self-assessment (2 min): Identify one thing you would do differently and why. Panels respect honest reflection over false confidence.

Speak clearly, maintain eye contact, and manage your time. A timer will be visible. Rushing through the SLD walk-through to save time for questions is a common mistake — practice the full sequence before defense day.