The appliance works perfectly. If you did it the other way around (50amps on a 30amp breaker, you would be tripping the breaker.
Think of it as a Mercury thermometer. The circuit breaker is the maximum temperature and the load on that breaker is the mercury. If the load is lower than the max, everything works beautifully. If the load becomes greater than the maximum rating, then things starting popping.
You cannot safely plug a 2000 watt 240v appliance into a 120v 20 amp breaker without risking damage or fire hazard. To use the appliance, consider installing a step-up transformer to convert the voltage from 120v to 240v before plugging it in. This will ensure the appliance operates correctly without overloading the circuit.
For a 7 amp appliance, you would typically use a 10 amp circuit breaker to provide sufficient protection. It is recommended to always use a breaker with a slightly higher rating than the appliance's current draw to prevent nuisance tripping and ensure safety.
If it is a 30 amp breaker then it is a 240 volt outlet.
If the appliance is just to be plugged into a circuit with multiple outlets then you just need to make sure that the sum of currents for all devices on the circuit are less than the rated current. A rule of thumb is total current should be no greater than 80% of the rated current. So you might have a 20 A breaker and several 2.5 A appliances on this circuit. If you have a dedicated circuit for the appliance you would only need to size the breaker for the maximum current being drawn by the appliance. If the appliance contained a motor then there might be a start-up current that might be as high as 15 amps so you would likely go to a 20 amp breaker for a safety margin. As a practical matter a dedicated circuit for an appliance in the 2.5 amp range should have a 15 amp breaker. I always install a 20 amp breaker just for added margin and possible future applications.
Probably not. If the appliance has multiple heating levels then you might get away with it. In this scenario you would only be able to use 30 amps of the appliance's 40 amp capacity before the breaker would trip.
Yes.
You cannot safely plug a 2000 watt 240v appliance into a 120v 20 amp breaker without risking damage or fire hazard. To use the appliance, consider installing a step-up transformer to convert the voltage from 120v to 240v before plugging it in. This will ensure the appliance operates correctly without overloading the circuit.
For a 7 amp appliance, you would typically use a 10 amp circuit breaker to provide sufficient protection. It is recommended to always use a breaker with a slightly higher rating than the appliance's current draw to prevent nuisance tripping and ensure safety.
If it is a 30 amp breaker then it is a 240 volt outlet.
If the appliance is just to be plugged into a circuit with multiple outlets then you just need to make sure that the sum of currents for all devices on the circuit are less than the rated current. A rule of thumb is total current should be no greater than 80% of the rated current. So you might have a 20 A breaker and several 2.5 A appliances on this circuit. If you have a dedicated circuit for the appliance you would only need to size the breaker for the maximum current being drawn by the appliance. If the appliance contained a motor then there might be a start-up current that might be as high as 15 amps so you would likely go to a 20 amp breaker for a safety margin. As a practical matter a dedicated circuit for an appliance in the 2.5 amp range should have a 15 amp breaker. I always install a 20 amp breaker just for added margin and possible future applications.
Probably not. If the appliance has multiple heating levels then you might get away with it. In this scenario you would only be able to use 30 amps of the appliance's 40 amp capacity before the breaker would trip.
In North America this size breaker could be used on a welding machine. A range in the home would use a 40 amp two pole breaker.
A 30 amp breaker is designed to trip at an earlier point than a larger 40 amp breaker so one appliance that operates on lower amperage level could be unsafe or damaged before it could trip the higher 40 amp breaker. Also, the existing wiring may not be rated for 40 amp service.
Yes, providing the phase is the same. but you can't do the other way around, or breaker will immediately pop, or fuse will blow.
Yes, you plug a 20 amp device into a 30 amp circuit. The circuit always needs to be equal or greater than the device. If you plug to large of an appliance into a circuit, the circuit breaker (or fuse) should open the circuit so that no damage occurs.
No, a breaker needs to be loaded less than 80 percent. As they reach their tripping point they get hot. The circuit rating, breaker and wiring is not designed for 21 amps. The next size would be a 25 to 30 amp breaker that has #10 wire feeding it.
Yes, if properly wired a 20 amp circuit is a great circuit for an 18 amp appliance. Properly wired means you've used 12 gauge wire or larger and the circuit is protected by a 20 amp breaker or fuse and all connections are secure.