Technically it's a 20 amp load (20A x 240V = 4800W). However, you should not run a breaker at full load. The breaker is to protect the wiring from overheating and from short circuits. You should use 10 gauge wire and a 30 amp double pole breaker.
i have a 4800 watt heater that's 240 volts. What size breaker is needed?
It could, it depends on what the manufacturer's nameplate reads as to the voltage and amperage of the heater.
If the heater is rated as a 3 phase 480 volt heater then a neutral is not needed. If the voltage stated is 277 volts three phase then a neutral is needed.
Watts = Amps x Volts. Amps = Watts/Volts = 4.16. The smallest breaker in a house panel is 15 amps. You will need a 2 pole 15 amp breaker. On a # 14 wire you can load that circuit up to 12 amps.
800 watts/ 240 Volts = 3.34 amps 14AWG wire with a 15 amp will do
The equation that you are looking for is I = W/E. Amps = Watts / Volts.
Home freezers run on 120 volts and require AWG #12 wire on a 20 amp breaker.
A 30 amp breaker wired with AWG #10 wire.
If the breaker is in the distribution panel and you have a volt meter check the circuit for 120 volts to the neutral or ground. If there is 120 volts present on the terminal the breaker is operational. Turn the breaker off, if the voltage disappears the breaker is operational. It is not recommended to do a load test on a breaker of this amperage due to the high wattage load needed to trip the breaker.
The electric furnace operates on 240 volts so a two pole breaker is needed.
To answer this question the voltage is needed. At 120 volts the current would be too high for a 70 amp breaker and for 240 volts the breaker rating would be too big.
The current is 500/110 amps and you add 25% so the answer is 6 amps.