Turning Off Your Main Breaker for Generator Use: What You Need to Know

Jun 08, 2025

Thinking of plugging in your camping generator and skipping the main breaker? Hold up—yes, you do need to turn it off (unless you like fireworks and fried circuits). Why? Backfeeding danger, legal rules, and safety risks. Stick around—we’ll break it down without zapping your brain.

The Critical Answer & Why It's Not Just a Suggestion

The Short Answer: Yes, and Here’s Why It’s Crucial

When a generator is connected to your home’s electrical system, switching off the main breaker is essential. It prevents electricity from flowing back into the grid, which can be extremely dangerous.

Backfeeding can injure utility workers and damage your system. It's not just about safety—it's about legal compliance too, especially in the UK.

This one simple action can make all the difference during a power outage.

Champion 2200-watt inverter generator on a white background.

What Happens if You DON'T Turn Off the Main Breaker?

Leaving the main breaker on allows the generator’s electricity to travel back into the grid. This creates a major risk—not just for your home, but for everyone connected to the power network.

It can result in electrocution hazards and unpredictable surges. Your appliances and wiring may also suffer damage.

This risk is avoidable, and switching off the breaker is one of the easiest ways to avoid it.

Understanding "Backfeeding": The #1 Danger to Utility Workers

Backfeeding happens when a generator sends power in reverse, flowing outward from your home and into external power lines.

This power isn’t supposed to be there. Workers assume the lines are safe during a blackout. A single mistake here can be fatal.

Preventing backfeeding is not optional—it’s an essential part of generator safety protocol.

Protecting Your Generator and Home Appliances from Damage

Aside from safety, leaving the breaker on can also destroy expensive equipment.

Backfeeding and surges can overload the generator. That strain may blow fuses or fry sensitive electronics like fridges, TVs, or routers.

Turning off the breaker reduces this risk. It protects your devices and ensures the generator runs smoothly under load.

Champion 3600-watt inverter generator in use outside a motorhome on grass.

How to Correctly Isolate Your Home from the Grid When Using a Generator

Option 1: The Transfer Switch (Manual & Automatic) – The Gold Standard

A transfer switch is the preferred solution for safely connecting a generator to your home. It allows for a clean switch between mains and backup power.

**How a Transfer Switch Works (and why you might not touch the original main breaker yourself)**

Installed next to your main panel, the transfer switch acts as a middleman. It either automatically or manually blocks power from flowing to or from the grid.

With this setup, you often don’t need to flip the main breaker manually—the switch handles isolation for you.

It’s tidy, safe, and legally compliant.

Option 2: The Interlock Kit – A Safe and Budget-Friendly Alternative

If a full transfer switch is too costly, an interlock kit is the next best thing.

It’s a mechanical device installed on your breaker panel that forces safe operation. Though it isn’t automatic, it ensures that you follow the correct sequence.

How an Interlock Kit Forces You to Turn Off the Main Breaker

An interlock prevents you from turning on the generator breaker unless the main breaker is off. It’s a physical safety mechanism.

You can’t accidentally backfeed with this in place—it makes it impossible to power the home from two sources at once.

It’s simple and cost-effective, and keeps you on the right side of safety rules.

What About Just Using Extension Cords Directly to Appliances?

Some people use camping generators to power just a few essentials, like a fridge or a kettle. In this case, they plug the generator directly into appliances using extension leads.

When this is okay (and why the main breaker isn't the issue here)

If you’re not feeding power into the home’s wiring, the breaker doesn’t matter.

There’s no connection to the grid—just a generator powering one or two devices directly.

This setup is common in campsites or cabins. But be sure to use proper outdoor-rated extension leads and never overload the generator.

The DANGEROUS Shortcut to Avoid: Illegal "Suicide Cords"

Never, under any circumstances, plug your generator into a wall socket using a male-to-male lead (often called a “suicide cord”).

This method is illegal, unsafe, and deadly. It creates a direct path for backfeeding.

It can electrocute you, your neighbours, or a utility worker—and it can cause electrical fires. If you're even thinking about trying this, stop now.

Beyond the Breaker: Essential Generator Safety You Can't Ignore

Key Safety Takeaways for Any Generator Hookup

Isolate your home from the grid
Never rely on makeshift or DIY setups
Use the right gear—transfer switches or interlocks
Keep your generator serviced
Follow UK installation regulations and standards

The Golden Rule: Preventing Backfeed at All Costs

No matter what your generator setup looks like, preventing backfeed is priority number one.

If you’re connected to your home’s wiring in any way, you must ensure the grid is disconnected. That either means flipping the main breaker or letting a transfer switch do it for you.

Two Champion 2000-watt dual fuel inverter generators connected and stacked outside an RV on a paved ground.

Carbon Monoxide (CO) Poisoning: The Silent Killer (Generator Placement)

Generators release carbon monoxide—a gas that’s invisible, scentless, and lethal.

Never run a generator indoors, in a garage, or near open windows. Always place it outside, well away from living spaces.

A good rule: if you wouldn’t park your car there with the engine running, don’t put your generator there either.

When in Doubt, Call a Qualified Electrician

UK regulations require that any electrical work—especially involving generators—be carried out by competent persons.

If you’re unsure about your setup or you want peace of mind, contact a qualified electrician.

It could be the best call you make during a blackout.

Other content you might like:

Back to Camping Generators Blog