Solar O&M Prep

OMAT Existing System Infrastructure Considerations: Tasks and Knowledge Items

28.3% of the OMAT exam

Existing System Infrastructure Considerations is 28.3% of the exam and has no counterpart by name on the PV Associate exam — but almost every one of its 24 knowledge items appears in the PVA JTA, inside Design and Installation. The regrouping is the point. PVA asks these questions from the position of someone specifying and building a system; OMAT asks them from the position of someone standing in front of a system that someone else built years ago, with a plan set that may or may not match what was installed.

Task 1: PV System Plan Sets

  1. Site plan and array layout
  2. Electrical diagrams (e.g., one-line or three-line diagrams, wiring diagram, string diagram)
  3. String configuration
  4. Conductor properties (e.g., temperature ratings, ampacity ratings, UV resistance, moisture rating)
  5. Electrical and plan set symbols
  6. Electrical equipment (e.g., wire, conduits, raceways, disconnects)
  7. Equipment data sheets and installation instructions
  8. Details (e.g., structural, electrical, grounding, labeling)

Task 2: Mounting Structure Types and Installation

  1. Types of mounting structure and components (e.g., flat roof, pitched roof, ground mount)
  2. Manufacturer manuals and specifications (e.g., installation manuals, site engineered plans)
  3. Roof considerations (e.g., type, pitch, warranty)
  4. Structural considerations (e.g., rafter, truss, stud, decking, beams, purlins, span, cantilever)
  5. Fastener types and sizes (e.g., metal, wood, concreter fasteners; material - stainless steel/galvanized; grade, strength markings, compatibility of metals/materials)
  6. Grounding and bonding methods (e.g., integrated grounding, listed grounding components, star washers)
  7. Common power and hand tools

Task 3: Electrical Equipment Installation

  1. Manufacturer manuals and specifications (e.g., termination torque specifications, NEMA ratings, sunlight exposure)
  2. Working clearances
  3. Common electrical fittings and uses (e.g., connectors, couplings, grounding bushings, strain reliefs, raceway)
  4. Labeling and marking requirements (e.g., code requirements, durability)
  5. Wiring best practices (e.g., PV connector compatibility, drip loops, service loops, minimum bend radius, support, exposure to damage)
  6. Material compatibility (e.g., conductor type, terminations, splices)

Task 4: Energy Storage Installation

  1. Common types of energy storage (e.g., lithium batteries, lead acid batteries)
  2. Manufacturer manuals and specifications (e.g., installation manuals, system programming and controls, product safety guidelines)
  3. Labeling and marking requirements (e.g., code requirements)