Contractors 
Contractors Executive Summary
- Solar interlock kits provide a safe, NEC-compliant way to backfeed solar power into an existing electrical panel.
- They mechanically prevent the main breaker and solar breaker from being on at the same time, protecting utility workers and your electrical system.
- Interlock kits are a cost-effective alternative to transfer switches, subpanels, and smart load centers.
- They allow you to keep everything in one panel, avoiding expensive rewiring or panel replacement.
- Proper panel spacing is critical, as breaker layout and spacing determine which interlock kit will fit safely.
- Kits are designed by panel size and layout, including breaker count, main breaker location, and adjacent breaker positioning.
- Compatible with most major panel brands, including Square D, Eaton, Siemens, and GE.
- Support future expansion, leaving room to integrate battery backup or a generator later.
- Expert support is available, with panel photo reviews to ensure the correct kit selection.
Investing in solar Interlockkit’s
As more homeowners invest in solar energy, finding a safe and affordable way to connect solar power to an existing electrical panel has become a common challenge. One of the most effective solutions is a solar interlock kit — a mechanical device that prevents both the main breaker and the solar backfeed breaker from being on at the same time. This ensures your system complies with National Electrical Code (NEC) requirements, protects utility workers, and allows you to safely backfeed power from your solar inverter.
Why Choose a Solar Interlock Kit?
Solar interlock kits are a simple, cost-effective alternative to expensive transfer switches, subpanels, or smart load centers. Instead of rewiring your home or replacing your panel, you can keep everything contained within your existing panel setup. That makes interlock kits a great option for retrofitting solar, integrating battery backup systems, or combining solar and generator sources in a single panel.
Why Panel Spacing Matters
The key to choosing the correct solar interlock kit comes down to one important factor: panel spacing. Every electrical panel is a little different. The number of spaces and circuits, the positioning of the main breaker, and the physical distance between breakers all affect which interlock kit will fit properly. If the spacing is off, even slightly, the interlock may not align correctly or may not function safely. That’s why our kits are named and classified based on the number of breaker spaces and the panel layout they are designed for.
How Kit Naming Works
Here’s how it works. A panel labeled as “30 space / 60 circuit” has 30 breaker slots that can accommodate full- or half-width breakers, supporting up to 60 circuits. Some panels have the main breaker located at the top, others have it center-fed. Some panels have adjacent main and solar breakers, while others have branch breakers between them. These physical differences are what determine the correct kit — and we’ve designed interlock models to match each configuration exactly.
Solar Interlock Kit Compatibility Chart
Below is a breakdown of our solar interlock kits and the panel sizes they are designed to fit. You can use this chart to cross-reference your panel size and find the exact kit that fits:
Keep Everything in One Panel
The main advantage of these kits is that they allow you to keep everything in one panel without needing to install a secondary solar subpanel. This not only saves money but simplifies installation and future service. For under a few hundred dollars, a solar interlock kit gives you NEC-compliant protection, integrates easily with most inverter systems, and leaves room for a generator connection if needed down the line.
Need Help Matching Your Kit?
If you’re unsure which interlock kit is right for your panel, just take a clear photo of the panel interior with the door open, showing the main breaker and surrounding breaker slots. Our team will match the correct kit based on your panel brand, breaker spacing, and layout. This ensures a safe, precise fit — no guesswork needed.
Make Your Panel Solar-Ready Today
Solar interlock kits are one of the most straightforward ways to make your home solar-ready. They’re reliable, affordable, and easy to install. Whether you’re working with a Square D, Eaton, Siemens, GE, or another major panel brand, we’ve got a solar kit designed to fit your panel safely and securely.
