Electrical safety
What is a changeover switch or ATS in a solar backup system?
A changeover switch (manual or automatic) selects which source feeds a circuit — grid, inverter backup, or generator — without back-feeding the utility. An ATS (automatic transfer switch) does this without you standing at the board. Correct interlocking protects municipal workers and your equipment; DIY “double feeds” are dangerous and illegal.
On hybrid systems the inverter often manages islanding internally — extra ATS hardware appears when generators or complex sub-boards are involved. Ask your electrician to explain the source-selection path in one sketch.
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