A UL-listed interlock kit and a 50-amp inlet turn your portable generator into whole-house backup. No extension cords through windows, no illegal double-male cords, no backfeeding the grid. Plug in, flip two breakers, and run your well pump, fridge, and lights until Duke gets the power back on.
A generator interlock kit is a steel sliding plate that mounts on your electrical panel. It makes it physically impossible to turn on your generator breaker while the main breaker is on. One or the other, never both. That mechanical guarantee is what makes it legal to feed generator power into your panel: your house can never push power back out onto Duke Energy’s lines, where it would electrocute a lineman working to restore your service.
The rest of the install is a weatherproof inlet box mounted outside, a heavy feeder cable from the inlet to a dedicated breaker in your panel, and the interlock plate matched to your exact panel model. When an outage hits, you roll out your portable generator, plug in one cord, shut the main off, flip the generator breaker on, and choose which circuits to run. The whole panel is available, you decide what’s worth the wattage.
This is the difference between a code-compliant backup power system and the extension-cord scramble most people do in the dark. It is also the upgrade insurance companies and inspectors actually approve of.
Typical installed price: interlock kit, 50A inlet box, breaker, feeder cable, permit, and inspection, all-in
What a whole-home standby generator system runs installed. The interlock covers most of the same outages for roughly a tenth of the cost
Time on site for most installs. Your power is only off for the panel work itself
Where you land in that range depends on three things: 30-amp or 50-amp inlet, how far the inlet box sits from your panel, and the condition of the panel itself. A 50-amp inlet a few feet from a modern panel with open breaker spaces is the low end. A long feeder run, a crowded panel, or a brand that needs a specific listed kit moves it up.
One honest caveat: interlock kits are made to match specific panel brands and models. Square D, Eaton, Siemens, and GE panels almost always have a listed kit available. If you have a Federal Pacific or Zinsco panel, there is no safe kit for it, and I will tell you that on the phone before I ever roll a truck. Those panels have bigger problems than backup power, and the right conversation is a panel replacement first.
Both of these are actual jobs, not staged demos. The first is a 50-amp inlet and interlock build: inlet mounted, feeder run, plate on, load test. The second is the meter combo install pictured above on this very page, permit closed, approved by both the county and the power company, with the part worth watching: the generator breaker physically refusing to turn on while the main is live. And it is not a demo rig: that customer ran his whole house on this setup through the weekend, including his AC unit, which honestly impressed me.
Every install ends the same way: inspection passed, instructional stickers on the panel, and the homeowner does the switchover themselves before I leave, cord in hand, not a manual on the counter.
Text me a photo of your panel with the door open. I identify the brand and model, confirm a listed interlock kit exists for it, and quote you a real number before any work starts. No listed kit for your panel means no install, and I will tell you why.
A generator inlet feeding a panel is permitted electrical work in South Carolina. I pull the permit, it passes through at cost, and the final inspection is part of the job. That paper trail matters when insurance ever asks questions.
A weatherproof 30A or 50A power inlet goes where it makes sense for your generator: near the driveway, behind the garage, out of sight from the porch. Then a properly sized feeder runs from the inlet to your panel.
The listed kit plate mounts on the panel face with its retention hardware, and a dedicated back-fed breaker lands in the panel. The plate physically blocks the generator breaker unless the main is off. That is the whole safety case, in steel.
We fire up your generator, transfer the panel over, and run your actual loads: well pump, fridge, lights. You do the switchover yourself while I watch. Then inspection, and you are storm-ready.
Sunset Electric is an authorized installer listed on InterlockKit.com, the manufacturer directory for listed generator interlock kits. Search Sunset, SC on their installer map and you will find us, phone number and all. Being in the directory means homeowners the manufacturer sends our way get the install done the way the listing requires: the correct kit for the exact panel model, the retention hardware installed, and the labeling in place.
That said, I am not married to one brand. I install whatever listed, panel-matched kit your panel calls for, whether that is the manufacturer’s kit, a Square D factory interlock, or an Eaton or Siemens factory part. The rule is simple: listed for your specific panel, or it does not go on.
If any of these sound familiar, an interlock kit is probably the highest-value electrical upgrade you can make this year.
It handled the last outage badly: cords everywhere, half the house dark, well pump dead. The generator is fine. It just needs a legal way into your panel.
A $9K to $18K standby system is a great product, and out of reach for a lot of households. An interlock gets you most of the coverage at a price that does not need financing.
The so-called suicide cord: two male ends, plugged into a dryer outlet. It backfeeds the grid, it can kill a lineman, and it is illegal for good reason. The interlock does the same job safely.
On a well, a power outage means no water within hours. A 240V well pump cannot run off an extension cord. Through the panel with an interlock, it runs like nothing happened.
Cords pinched in window sashes, taped across floors, feeding the fridge and not much else. One inlet cord replaces all of it, and the whole panel becomes available.
Second homes around Keowee ride out outages unattended. An interlock plus a generator in the garage means whoever checks on the place can have heat and light running in five minutes.
Have a question not listed here? Call or text (864) 436-8680. I’m happy to talk through it.
Text a photo of your panel with the door open to (864) 436-8680 and you’ll have a firm price today. One visit later, your portable generator runs the house.
Mon–Fri · 8am–6pm · Same-day emergency service available
Storm-season warning: Never connect a generator to your house with a double-male cord through a dryer or welder outlet. It backfeeds the utility lines, it can kill the lineman restoring your power, and it can destroy your generator when the grid comes back. If that is your current outage plan, call me before the next storm instead.