A changeover switch connects your circuits to one power source at a time: the grid, a generator or an inverter. An automatic transfer switch (ATS) detects a power failure and switches over by itself (starting the generator if configured). Crucially, it prevents two sources connecting together, which would be dangerous for your equipment and for line workers.
Key takeaways
- One source at a time: grid, generator or inverter.
- Automatic (ATS) or manual versions.
- Prevents back-feeding the grid.
- Must be installed by a qualified electrician.
01How it works
02Manual vs automatic
Manual
Automatic (ATS)
03Safety
For security systems, a UPS or inverter still bridges the gap while an ATS and generator take over. See solar backup for security systems and electrical installation.
04Frequently asked questions
What is an ATS?
An automatic transfer switch: it switches your supply from the grid to a generator (or other source) automatically when the grid fails.
Can I connect a generator to a socket?
No. That's dangerous. A proper changeover must be installed.
Will my CCTV reboot when the changeover switches?
Unless it's on a UPS or inverter, there's usually a short gap. A UPS prevents the reboot.
