Electrical draw = cooling power ÷ efficiency: a 1.5T unit moves 5.28 kW of heat; at ISEER 5.10 that costs 1.03 kW of electricity, or ~4.5 A at 230 V. The same maths at SEER2-class efficiency puts a 3-ton US system near 3.1 kW / 13 A at 240 V. The ampere calculator does this with breaker suggestions.
Continuous-load practice sizes the breaker at 125% of running current, then rounds to a standard rating (10/16/20/25/32 A MCBs in India; 15/20/30/40 A breakers in the US — the condenser's plate states 'Max Fuse/Breaker', which governs). Non-inverter compressors pull 3–6× inrush at start; C-curve MCBs and HACR-rated breakers tolerate this. Undersized wiring, not the breaker, is the fire risk — wire gauge must match the breaker.
An AC sharing a circuit with other loads nuisance-trips and browns out the compressor at start. Every fixed AC gets its own circuit from the panel. Long cable runs to terrace condensers should be checked for voltage drop — keep it under 3% (our sister tool voltdropcalc.com covers this). All of this is an electrician's job; the calculators are for informed conversations, not DIY.
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A 5★ inverter drawing ~4.5–5 A runs comfortably on a 10 A or 16 A C-curve MCB on a dedicated circuit; 16 A is the common Indian practice. Follow the manufacturer's plate where stated.
No — extension cords aren't rated for continuous compressor loads and create fire risk. Fixed ACs need fixed, dedicated wiring.
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