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    Generator Changeover Switch: Why Back-Feeding Your House Is Dangerous

    Plugging a generator straight into a wall plug can kill someone and wreck your appliances. Why a proper changeover switch is essential in Johannesburg, and what it costs.

    30 May 2026 6 min read
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    A generator is only as safe as the way it is connected — and the cheap way is genuinely deadly. If you own or are buying a generator for load-shedding, the changeover switch is the part you must not skip.

    What "back-feeding" is, and why it kills

    Connecting a generator to your home through a wall plug (a so-called "suicide cord") pushes power backwards through your wiring and out into the municipal network. A line worker who believes the power is off can be electrocuted by your generator. And when grid power returns while your generator is still connected, the clash can destroy your generator and appliances.

    What a changeover switch does

    A changeover switch safely isolates your home from the grid before the generator is connected, so power can only flow one way. It is the safe, compliant, legal way to run your home on a generator.

    Manual vs automatic

    • Manual changeover switch — affordable; you flip it when the power goes. Perfect for most homes.
    • Automatic transfer switch (ATS) — detects the outage and switches over for you, ideal for unattended or essential supply.

    See our generator changeover switch service.

    It needs a registered electrician and a COC

    A changeover switch ties into your DB board and must be installed and certified with an Electrical COC. If you would rather have seamless, silent backup, ask us about an inverter instead. Get it connected safely.

    Frequently Asked Questions

    A changeover switch safely isolates your home from the municipal grid before connecting the generator, so power cannot flow back into the street. Without one, 'back-feeding' through a wall plug can electrocute someone working on the line, and when grid power returns it can destroy your generator and appliances. A changeover switch is the safe, legal way to connect a generator.

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