Alternative Supply Circuits
Alternative Supply Circuit Labels
Used to mark the main switch or circuit breaker feeding an alternative power source — solar inverter, battery storage, or backup generator — at a switchboard that also has a grid connection.
Where an installation has more than one power source, whoever isolates supply next (an electrician, emergency services, or another trade) needs to know at a glance which switch controls which source. Switching off the grid main doesn't mean the board is dead if solar, battery, or a generator is still feeding in behind it — that's the exact scenario these labels exist to prevent. Fitted alongside the "Main Switch (Grid)" label and, where the board has more than one supply, a broader multiple-supply warning notice.
This is grounded in the AS/NZS 3000 / AS/NZS 4777.1:2024 requirement to label alternative-supply main switches distinctly from the grid main switch, so isolation is done safely.
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