Quick answers: wire, breaker, battery and solar sizes
The sizes people ask about most, worked out the same way as the lab's calculators and safety check, for 230 V (the Philippines, PEC) and 120/240 V (the US, NEC). Each answer has the reasoning in three lines and opens on the bench.
Breaker and wire for an appliance
What breaker and wire for a 1 HP aircon?
20 A on 3.5 mm² (230 V) · 20 A on 12 AWG (US)
What breaker and wire for a 1.5 HP aircon?
20 A on 3.5 mm² (230 V) · 20 A on 12 AWG (US)
What breaker and wire for a 2 HP aircon?
20 A on 3.5 mm² (230 V) · 20 A on 12 AWG (US)
What breaker and wire for a 2.5 HP aircon?
20 A on 3.5 mm² (230 V) · 20 A on 12 AWG (US)
What breaker and wire for a 3.5 kW water heater?
20 A on 3.5 mm² (230 V) · 20 A on 12 AWG (US)
What breaker and wire for a 5 kW water heater?
30 A on 5.5 mm² (230 V) · 30 A on 10 AWG (US)
What breaker and wire for a 2 kW induction cooker?
15 A on 2 mm² (230 V) · 15 A on 14 AWG (US)
What breaker and wire for a 7 kW EV charger?
40 A on 8 mm² (230 V) · 40 A on 8 AWG (US)
What breaker and wire for a 1 HP water pump?
20 A on 3.5 mm² (230 V) · 20 A on 12 AWG (US)
What breaker and wire for a refrigerator?
20 A on 3.5 mm² (230 V) · 20 A on 12 AWG (US)
Inverter battery breaker and cable
What breaker and cable for a 1,000 W inverter?
12 V: 125 A · 24 V: 63 A · 48 V: 32 A
What breaker and cable for a 1,500 W inverter?
12 V: 200 A · 24 V: 100 A · 48 V: 50 A
What breaker and cable for a 2,000 W inverter?
12 V: 250 A · 24 V: 125 A · 48 V: 63 A
What breaker and cable for a 3,000 W inverter?
24 V: 200 A · 48 V: 100 A
What breaker and cable for a 5,000 W inverter?
48 V: 160 A
Battery size for a load
How big a battery to run 100 W?
5 h: 617 Wh LiFePO4 · 25 Ah at 24 V
How big a battery to run 300 W?
5 h: 1,852 Wh LiFePO4 · 73 Ah at 24 V
How big a battery to run 500 W?
5 h: 3,086 Wh LiFePO4 · 121 Ah at 24 V
How big a battery to run 1,000 W?
5 h: 6,173 Wh LiFePO4 · 242 Ah at 24 V
How big a battery to run 2,000 W?
5 h: 12,346 Wh LiFePO4 · 483 Ah at 24 V
Solar panels for a daily use
How many solar panels for 1 kWh a day?
300 W · 1 × 550 W at 4.5 sun hours
How many solar panels for 2 kWh a day?
600 W · 2 × 550 W at 4.5 sun hours
How many solar panels for 3 kWh a day?
890 W · 2 × 550 W at 4.5 sun hours
How many solar panels for 5 kWh a day?
1,490 W · 3 × 550 W at 4.5 sun hours
How many solar panels for 10 kWh a day?
2,970 W · 6 × 550 W at 4.5 sun hours
How many solar panels for 20 kWh a day?
5,930 W · 11 × 550 W at 4.5 sun hours
Something else? The calculators work out any size, and the lab lets you build it and test it.