1. Introduction
Understanding the correct placement and connection of solar panels and inverters is crucial for ensuring system efficiency, compliance with Victoria Standards (AS/NZS 5033, AS/NZS 4777.1), and long-term performance. This guide provides Victoria-specific requirements and industry best practices.
2. Solar Panel Orientation & Tilt (Pitch)
2.1 Ideal Orientation
- Best direction: True North (maximises sunlight exposure throughout the day).
- Acceptable variations: Panels can face North-East to North-West with minimal production loss (~5–10%).
- East-facing panels: Higher production in the morning, lower in the afternoon.
- West-facing panels: Higher production in the afternoon, lower in the morning.
- South-facing panels: Least preferred; generally used only in space-limited sites or where feed-in is high and morning/afternoon production is not critical.
2.2 Roof Pitch Guideline
- Ideal tilt in Victoria: 20–30° (matches the sun’s average elevation).
- Flat roofs: Panels should be mounted on tilt frames to achieve 10–30° inclination.
- Too steep (>40°): May cause shading from adjacent rows and increase wind loading.
2.3 Why It Matters
- Incorrect tilt or orientation reduces annual energy output.
- Poor orientation can also affect voltage/current consistency in strings.
3. Panel Location Selection
When choosing panel placement:
- Avoid Shading: Even partial shading reduces output disproportionately (due to bypass diodes and string effect).
- Structural Integrity: Roof must be strong enough to hold panel weight (~12–15 kg per panel).
- Access for Maintenance: Maintain minimum 200 mm clearance from roof edges for safety and wind load compliance.
- Fire Safety Compliance: Keep clear of roof ridge/edges to allow fire personnel access (AS/NZS 5033).
- Separation of Arrays: Maintain required distances between different orientations to avoid cross-shading.
4. String Connection Requirements
4.1 Voltage & Current
- Minimum string voltage: Must be above inverter’s MPPT minimum voltage (check datasheet; typically 120–200 V).
- Maximum string voltage: Must not exceed 600 V DC for residential (AS/NZS 5033).
- String current: Must be within panel and inverter limits (usually 9–15 A per string).
4.2 String Design Rules
- All panels in a string should have same tilt, orientation, and shading conditions.
- Avoid mixing panels of different types or power ratings in the same string.
- Parallel strings: Should have equal string lengths and identical panel specs.
- MPPT Usage: Separate orientations should be connected to different MPPT inputs when possible.
4.3 Why This Matters
- Incorrect string sizing can lead to inverter shutdowns, reduced efficiency, or premature equipment failure.
5. Inverter Location Requirements
5.1 Placement
- Must be installed in a cool, shaded, well-ventilated area.
- Avoid direct sun exposure to reduce heat stress (which lowers efficiency).
- Should be accessible for maintenance and within 2 m height for easy service.
- Install on non-combustible surfaces (brick, concrete) where possible.
5.2 Electrical Compliance
- DC isolators must be adjacent to the inverter, weatherproof, and compliant with AS/NZS 5033.
- Ensure adequate cable management to avoid UV damage or tripping hazards.
- If wall mounting is not possible, use a free-standing frame with canopy.
6. Canopy Requirements
In Victoria, canopy installation is recommended when:
- Inverter is mounted outdoors in a location exposed to sun or rain.
- Manufacturer installation manual specifies shading/weather protection for warranty validity.
Best practice canopy features:
- Non-combustible material.
- Overhang should extend at least 150 mm beyond inverter edges.
- Height clearance should not obstruct airflow around the inverter.
7. Summary Table
Item | Standard / Best Practice | Why It Matters |
Orientation | True North ± 45° | Maximises yearly yield |
Tilt | 20–30° | Matches sun angle for Victoria |
Max String Voltage | ≤ 600 V DC | Safety & AS/NZS 5033 complianc |
Inverter Location | Cool, shaded, ventilated | Prevents overheating |
Canopy Use | Outdoors, sun/rain areas | Protects inverter & warranty |
8. References
- AS/NZS 5033:2021 – Installation and safety requirements for photovoltaic (PV) arrays
- AS/NZS 4777.1:2016 – Grid connection of energy systems via inverters
- SAA accredited installer Guidelines
