Executive Summary
- Interlock kits are matched to your panel, not your generator. The right fit depends on your panel’s brand, series, and breaker layout.
- The three things that determine your kit are the panel manufacturer and series, your main breaker amperage, and the distance between the main breaker and the breaker column.
- Some kits, like the K-1315, fit multiple panels and amperage ratings because those panels share the same standard 2-pole breaker layout.
- The easiest way to find your match is to text a photo of your panel with the breakers visible to (804) 400-5803. We’ll reply with the exact interlock kit that fits your panel, no guessing required.
- Your panel’s catalog number (usually on the label inside the door) can also help confirm a match.
How Interlock Kits Are Matched to Your Panel
Generator interlock kits are matched to your panel, not your generator. A kit has to line up with your panel’s breaker spacing and sit correctly relative to the main breaker, which is why getting the match right matters before you order. That doesn’t always mean there’s one exact kit per panel. Many of our kits, like the K-1315, fit several different panels because those panels share the same standard 2-pole breaker layout, while others are specific to a single series. Either way, the goal is the same: confirm the right fit before you buy. Luckily, everything you need to do so is usually right there on your panel, and you can find that information in under a minute with no tools.
What to Look for on Your Panel
Start with what’s already visible, because you don’t need to open or remove anything to gather the essentials. With the panel door closed, or just the outer door open, look for the manufacturer or brand first. Names like Square D, Eaton, Siemens, GE, Murray, and Cutler-Hammer are usually stamped on the panel door, the front cover, or a label near the top. Next, find the main breaker amperage by looking at the largest breaker, typically at the top or bottom of the column, which will read 100, 125, 150, or 200 amps. That number is one of the biggest factors in which kit fits. Finally, look for the series or line name, such as Square D’s QO or Homeline, or Eaton’s BR or CH, which is often printed on the label or molded into the cover.
The Easiest Way to Get Matched
The best and fastest way to get matched is to text a photo of your panel to (804) 400-5803 with the breakers showing. Just open the panel door so the breaker handles and main breaker are visible, snap the picture, and send it over. That single image shows us the brand, the main breaker, and the distance between the main breaker and the breaker column, which is everything we need to match you to the exact kit, multi-panel options included. No measuring, no part numbers, no guessing.
Can't Send a Photo?
If you can’t send a photo, your panel’s catalog number can also help. It’s usually on the label inside the door or on the side wall of the box alongside the voltage and bus rating. One thing to note: if accessing that label would mean removing the dead-front cover, don’t. That exposes live conductors and should be left to a licensed electrician. The brand, series, and main breaker amperage visible on the panel face are enough for us to get you matched even without it.
A Note on Installation
A safety note is worth repeating here. An interlock kit is a code-compliant way to back-feed your panel from a generator without the danger of an open transfer, but the installation involves your main service panel. Confirm your local code requirements and have a licensed electrician handle the install. It protects your warranty, your inspection, and the people working on your lines.
