How to Connect Solar Panels to an Inverter — Wiring Guide

Properly connecting solar panels to your inverter is critical for system safety and maximum performance. Incorrect wiring can damage your inverter, void your warranty, or create fire hazards. This guide covers the fundamentals of panel-to-inverter wiring for Deye hybrid inverters.

Understanding Series and Parallel Connections

Series Connection (Most Common)

Connecting panels in series adds their voltages together while keeping current the same. This is the standard configuration for string inverters and Deye hybrid inverters.

• Connect the positive (+) of one panel to the negative (-) of the next
• String voltage = sum of all panel Voc voltages
• String current = same as one panel's Isc

Parallel Connection

Connecting panels in parallel adds currents while keeping voltage the same. Used when you need to keep voltage low or when panels face different orientations.

Sizing Your String for Deye Inverters

Deye hybrid inverters typically accept 150-850V DC per MPPT input. You must ensure your string voltage stays within this range under all conditions.

Calculation Steps

1. Maximum string voltage: Number of panels x Voc x temperature correction factor (1.15 for cold mornings)
2. Minimum string voltage: Number of panels x Vmp x temperature correction factor (0.85 for hot afternoons)
3. Verify: Max voltage must be under 850V; Min voltage must be above 150V

Example: 550W Panels with Deye SUN-8K

Step-by-Step Wiring Process

1. Cover panels: Block sunlight with opaque covers before wiring to prevent shock
2. Connect panels in series: Use MC4 connectors to chain panels positive-to-negative
3. Route cables: Use UV-rated solar cable (4mm2 or 6mm2) through conduit
4. Install DC isolator: Mount between panel strings and inverter (required by UAE code)
5. Connect to inverter: Insert MC4 leads into the corresponding MPPT input terminals
6. Verify polarity: Use a multimeter to confirm correct positive and negative before energising

Common Mistakes

• Exceeding voltage limits: Permanently damages the inverter — not covered by warranty
• Reversed polarity: Can blow the inverter's DC fuse or damage MPPT circuits
• Mixing panel types: Different wattage/voltage panels in the same string causes mismatch losses
• No DC isolator: Violates UAE electrical codes and creates safety hazards