DIY Solar Panel Wiring: How to Connect Your Panels to an Inverter (Beginner’s Guide)

Posted on by Solar Genie

Ready to harness the sun’s power? One of the most crucial steps in setting up a DIY solar system is wiring your solar panels to your inverter. Whether you’re powering a shed, cabin, RV, or your home, this guide will walk you through the process safely and simply.

🔧 What You’ll Learn:

  • Basic solar wiring concepts
  • Types of wiring configurations (series, parallel, series-parallel)
  • How to safely connect panels to an inverter
  • Wiring diagram examples for each setup

🧠 Before You Begin: Understand the Basics

To wire your solar panels to an inverter, you need to understand the core components in the system:

  1. Solar Panels – generate DC electricity.
  2. Charge Controller (for battery systems) – regulates voltage going to batteries.
  3. Battery Bank (optional) – stores energy for later use.
  4. Inverter – converts DC to usable AC power.

If you’re using a grid-tie or hybrid inverter with MPPT inputs, you might not need a charge controller or batteries. Off-grid systems, on the other hand, typically include both.

⚡ Series vs. Parallel Panel Wiring

🔌 Series Wiring

  • Voltage adds, current stays the same.
  • Ideal when you need higher voltage (e.g., for MPPT inverters).
  • Example: Three 12V panels in series = 36V.
[+] Panel 1 [-] --- [+] Panel 2 [-] --- [+] Panel 3 [-] → to inverter input

🔌 Parallel Wiring

  • Current adds, voltage stays the same.
  • Best when keeping voltage low, like in 12V systems.
  • Requires combiner box or parallel connectors.
[+] Panel 1 ─┐
[+] Panel 2 ─┼─→ Positive to inverter
[+] Panel 3 ─┘

[-] Panel 1 ─┐
[-] Panel 2 ─┼─→ Negative to inverter
[-] Panel 3 ─┘

⚡ Series-Parallel Wiring

Used in larger systems to balance voltage and current. Combine groups of panels in series, then parallel those groups.

🛠️ How to Connect Panels to Your Inverter (Step-by-Step)

Step 1: Plan Your Voltage & Current

Match your panel array’s output voltage to your inverter’s input range. Check inverter specs for safe voltage (Voc) and current limits.

Step 2: Choose Your Wiring Configuration

Series for higher voltage, better MPPT efficiency. Parallel for safer low-voltage setups (12V/24V).

Step 3: Use Correct Wire Size

Use an online voltage drop calculator. For 12V/24V, wire size matters more due to higher current.

Distance 12V System 24V System 48V System
<10 ft 10 AWG 12 AWG 14 AWG
10–20 ft 8 AWG 10 AWG 12 AWG
20–30 ft 6 AWG 8 AWG 10 AWG

Step 4: Install Safety Components

  • Fuses or breakers for each string or array.
  • Disconnect switches between panels and inverter.
  • Combiner box for multiple panel strings.

Step 5: Make the Connection

  • Connect panel output (via combiner or directly) to inverter DC input.
  • Observe polarity: Positive to positive, negative to negative.
  • Tighten terminals and secure cables to prevent movement.

🔋 Off-Grid Example Setup

Equipment:

  • 4x 100W 12V solar panels
  • 24V battery bank
  • MPPT charge controller (150V input max)
  • 24V inverter

Wiring Plan:

  • Wire 2 panels in series → 24V
  • Wire the other 2 in series → 24V
  • Then, parallel the two series strings
  • Send output to charge controller → battery bank → inverter

☀️ Grid-Tie Example Setup (No Battery)

Equipment:

  • 6x 300W panels (VOC = 40V)
  • Grid-tie inverter (input 120–450V DC)

Wiring Plan:

  • Wire all 6 panels in series: 6 x 40V = 240V (well within inverter range)
  • Connect directly to inverter input using MC4 connectors and PV wire

🛡️ Safety Tips

  • Always work on solar systems with the disconnect switch off.
  • Wear gloves and eye protection.
  • Double-check voltage with a multimeter before making connections.
  • Ensure components are rated for outdoor use and properly grounded.

📌 Final Thoughts

Connecting solar panels to an inverter may sound intimidating, but it’s completely doable with a clear plan and safety in mind. Once wired, you’ll be generating clean power from the sun and reducing your reliance on the grid—or going completely off-grid!

Whether you’re powering a tiny home or a workshop, understanding how to wire your solar panels properly is the foundation of any successful DIY solar setup.

Need help with your setup? Drop a comment below or check out our Solar System Wiring Diagrams and Tools & Resources pages for more guides!

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