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NABCEP PVIS study materials
NABCEP PVIS study resources

NABCEP PVIS: PV Installation Professional (PVIP): Code-Compliant Design, Installation, and Commissioning

NABCEP PVIS · Work through your exam, one topic at a time.

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PV Installation Professional (PVIP): Code-Compliant Design, Installation, and Commissioning

The NABCEP PV Installation Professional (PVIP) exam tests the integrated judgment of a lead installer across site assessment, electrical design, installation, commissioning, and troubleshooting. The source does not enumerate separate domains, so this section treats PVIP as one system-level domain. Expect calculation items from NEC Article 690, interconnection rules from Article 705, and safety items from OSHA and NFPA 70E.

Core code rules

  • Current: PV source and output circuit current is Isc × 1.25 (690.8(A)). Conductor ampacity after temperature and conduit adjustment must be at least 1.25 × that current (690.8(B)); the OCPD must be at least 1.25 × Isc and not exceed conductor ampacity.
  • Voltage: Calculate maximum system voltage at the coldest expected module temperature using 690.7, not STC Voc.
  • Rapid shutdown: 690.12 requires controlled conductors outside the array boundary to be reduced to 30 V and 240 VA within 30 seconds; the 2023 NEC permits 80 V inside the boundary.
  • Interconnection: For load-side 705 connections, apply the 120% busbar rule; supply-side connections need a dedicated disconnect.
  • Grounding: 690.41–690.47 require equipment grounding, a grounding electrode conductor, and single-point grounding of array frames.
  • Safety: OSHA 1926.501 fall protection at 6 ft; lockout/tagout; arc-rated PPE per NFPA 70E.

Worked example

Module Voc 41.2 V, temp coefficient -0.29%/°C, design low -10°C. ΔT = -35°C. Correction = 1 + (-0.0029 × -35) = 1.1015. Cold Voc = 41.2 × 1.1015 = 45.4 V. Ten modules = 454 V. If inverter max DC input is 500 V, the string is acceptable; STC Voc would show 412 V and hide the cold-weather risk.

Traps

Using STC Voc instead of the cold-corrected value; adding bifacial rear-side gain to voltage without the manufacturer’s method; applying the 1.25 factor twice; using 690.7 on current; mismatching MC4-style connectors from different manufacturers; omitting the rapid-shutdown boundary; and failing to torque lugs or verify polarity before energizing.