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
- Maximum string voltage: Number of panels x Voc x temperature correction factor (1.15 for cold mornings)
- Minimum string voltage: Number of panels x Vmp x temperature correction factor (0.85 for hot afternoons)
- Verify: Max voltage must be under 850V; Min voltage must be above 150V
Example: 550W Panels with Deye SUN-8K
| Panels per String | Max Voc (cold) | Min Vmp (hot) | Status |
|---|---|---|---|
| 6 | 342V | 226V | OK |
| 7 | 399V | 264V | OK (recommended) |
| 8 | 456V | 301V | OK |
| 14 | 798V | 527V | OK (max for 2 strings of 7) |
| 15 | 855V | 565V | EXCEEDS 850V LIMIT |
Step-by-Step Wiring Process
- Cover panels: Block sunlight with opaque covers before wiring to prevent shock
- Connect panels in series: Use MC4 connectors to chain panels positive-to-negative
- Route cables: Use UV-rated solar cable (4mm2 or 6mm2) through conduit
- Install DC isolator: Mount between panel strings and inverter (required by UAE code)
- Connect to inverter: Insert MC4 leads into the corresponding MPPT input terminals
- 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
Frequently Asked Questions
How many solar panels can I connect to a Deye inverter?
The number depends on panel voltage and inverter MPPT range (150-850V). For typical 550W panels with ~49.5V Voc, you can safely connect 7-8 panels per string. A Deye SUN-8K with 2 MPPT inputs handles 14-16 panels total in two strings of 7-8.
Should I wire solar panels in series or parallel?
Series is the standard for Deye hybrid inverters. It raises voltage to the MPPT range (150-850V) efficiently. Parallel wiring is only used when panels face different orientations or when string voltage would exceed limits.
What happens if I exceed the maximum voltage on my Deye inverter?
Exceeding the 850V DC maximum will permanently damage the inverter's MPPT circuits. This damage is not covered by warranty. Always calculate maximum string voltage using Voc with a cold-temperature correction factor of 1.15.
