How to Make Your Own PV Solar Cables with MC4 Connectors | DIY RV Solar Wiring Guide

If you’ve ever installed or expanded your RV solar system, you’ve probably realized that finding the right length of solar cable can be a challenge. Instead of buying pre-cut cables that may be too long or too short, you can easily make your own custom PV solar cables using MC4 connectors.

In this week’s Todd’s Two-Minute Tech Tip Tuesday, brought to you by Big Beard Battery, Todd Henson walks through how to build your own PV cable step-by-step — saving you time, money, and frustration on your next solar install.

What Is a PV Cable — and Why It Matters

Before we start cutting wires, let’s cover the basics. PV stands for photovoltaic, which means “converting sunlight into electricity.” PV cable is specifically designed for solar applications — especially those mounted on your RV’s roof where it’s exposed to UV rays, heat, oil, and water.

Using true PV-rated wire ensures long-term durability and prevents damage or power loss. Most RV and residential solar systems use 10-gauge PV wire, which balances flexibility and current-carrying capacity for common solar arrays.

What You’ll Need

Here’s a quick list of the materials and tools Todd uses in the video:

✅ PV cable (10-gauge, sunlight-resistant)

✅ MC4 connectors (male and female)

✅ Wire cutters — for trimming to your exact length

✅ Wire strippers — to remove the sheathing cleanly

✅ MC4 crimping tool — for secure, professional-grade connections

These simple tools allow you to build custom-length solar cables that fit perfectly between your panels, combiner box, or charge controller.

Step-by-Step: How to Build Your Own PV Solar Cable

1. Cut the PV cable to your desired lengthUse your cable cutters to trim your PV wire to the exact length needed for your setup. Measure twice, cut once — extra slack can lead to clutter and voltage drop.

2. Strip the insulationUse a pair of quality wire strippers with a 10-gauge slot to remove just enough sheathing so the copper conductor fits under the MC4 connector’s “dog ears.” Don’t over-strip — you want a snug, secure fit.

3. Crimp on the MC4 connector pinsSlide the stripped wire into the MC4 pin (male or female). Then use your MC4 crimper with the proper die size. Give it a firm squeeze to ensure a solid electrical and mechanical connection.

4. Insert the pin into the connector housingPlace the crimped pin into the MC4 barrel — the larger pin goes into the male connector, the smaller into the female. Push until you hear it click into place. That sound means it’s locked and secure.

5. Tighten the sealScrew the outer locking collar down tight to ensure a waterproof connection. If your hand strength isn’t great, MC4 wrenches can help snug everything down perfectly.

Once you’re done, you’ll have a custom-length solar cable ready to connect your panels — one end male, one end female — designed exactly for your RV solar layout.

Why Make Your Own Solar Cables?

Making your own PV cables gives you more flexibility and control over your solar installation. Here are some key benefits:

🔋 Custom Fit: No more excess wire coiled on your roof or cables that come up short.💰 Cost Savings: Bulk PV wire and connectors are cheaper than buying pre-made lengths.🧰 Knowledge: When you build it yourself, you understand your system and can repair or modify it later.☀️ Professional Results: Using proper tools like MC4 crimpers gives you a clean, safe, and reliable connection that lasts.

Big Beard Battery: Powering Your Off-Grid Confidence

At Big Beard Battery, we’re not just about high-capacity lithium batteries like The Beast — we’re about empowering DIYers with the knowledge to take charge of their own power systems. Whether you’re wiring your first solar panel or installing a full off-grid setup, our products and training help you do it right the first time.

Ready to level up your RV solar system? Visit BigBeardBattery.com to explore our DIY solar kits, lithium batteries, and hands-on solar clinics.