Aircon branch circuit: 1.5 HP on 3.5 mm² and a 20 A breaker, on its own
Mains through a 20 A breaker and 3.5 mm² wire to a 1.5 HP non-inverter aircon on its own outlet. The tests share the circuit with the kitchen and swap in 2.0 mm² to see what gives. An aircon gets its own circuit: 3.5 mm² THHN (12 AWG) on a 20 A breaker for a 1 HP or 1.5 HP unit, 5.5 mm² on 30 A for 2 HP and up. The running current is modest (a 1.5 HP draws about 6 A) but every start pulls about 40 A for half a second, and a circuit shared with the kitchen is what trips. Philippine Electrical Code practice: lighting on 2.0 mm² (14 AWG) and a 15–20 A breaker (here 10 A), outlets on 3.5 mm² (12 AWG) and a 20 A breaker, big appliances on their own circuit.
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Parts list
Test procedure
Each test has an expected value and a pass range, like a factory test sheet:
- Running current, 1.5 HP
- Start surge seen by the breaker
- Cable sized for the breaker
- A 2 HP aircon, and the kitchen outlet on the same 20 A: two kettles and the flat iron
- Short circuit in a damaged aircon cord
How it works
What it does: Mains through a 20 A breaker and 3.5 mm² wire to a 1.5 HP non-inverter aircon on its own outlet. The tests share the circuit with the kitchen and swap in 2.0 mm² to see what gives.
Build it (guided or ready-made), then run its test procedure below. Every test has an expected value and a pass range, just like a factory test sheet.
Background
Anong breaker at wire ang para sa aircon? 3.5 mm² and 20 A for 1 to 1.5 HP; 5.5 mm² and 30 A for 2 HP; always its own circuit from the panel.
More builds: power, transformers and three-phase
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- Light with one switch
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- Fan and light on a 2-gang switch
- Outlet circuit: three outlets on a 20 A breaker
- House panel: main breaker and four branch circuits
- RCD protection: someone touches a live wire
- Water heater circuit: 3.5 kW on 5.5 mm² and a 30 A breaker