Some miniature circuit breaker knowledge and case you must know

① What is the difference between 1P, 1P+N and 2P MCB?

Answer:

For miniature circuit breakers, 1P + N, 1P, 2P are generally used as a single-phase appliances on and off control, but the effect is different.

1P------ single-pole circuit breaker with thermal magnetic release function, controlling only the fire line (phase line), modulus 18mm.

1P + N---- single-pole + N circuit breaker, while controlling the fire line, zero line, but only the fire line has a thermal magnetic decoupling function; module number is also 18mm.

2P ------ single-phase 2-pole circuit breaker, while controlling the fire line, zero line, and both have a thermal magnetic decoupling function, the modulus is 2 * 18mm = 36mm. 

 Therefore, the following conclusions can be drawn.

1, in order to reduce costs, with 1P can, but the upper circuit breaker must have a leakage release function, in order to prevent the fire, zero misalignment caused by accidents, must cut off the upper power supply.

2, to avoid the problem of 1 article when overhauling, available 1P + N (i.e. DPN).

3, with 2P reason: for the same 18mm module circuit breaker shell, the internal installation of 1P and 1P + N is a difference, the former in the short circuit accident state "limit breaking capacity" is certainly higher than the latter, after all, space is an important factor affecting the breaking capacity. Therefore, for more important, frequent maintenance and operation, prone to failure of the power circuit, it is best to use 2P (higher cost).

4, with 1P premise is that the lighting distribution box must have the function of leakage disconnect, at least into the line (or out of the upper level) to use leakage circuit breakers.

② detailed explanation of the circuit breaker 1P, 1P + N, 2P, 3P, 3P + N, 4P.

A: 1P, 2P, 3P, 4P is the number of poles, indicating the ability to segment a few lines. Now +N, are N line break, but the N line is not set off the device. Only the phase line break when the N line incidentally cut off. For example, 4P 16A circuit breaker, N line current if greater than 16A, or, say, greater than 20A, theoretically, the circuit breaker will trip. But the 3P + N circuit breakers, N line current 160A, will not trip. The premise is that the phase line current are not more than the rated value.

③ What appliances are in use for 1P, 2P and 3P? What is the difference between them?

A: 1P, 2P single-phase equipment, lighting can use 1P, sockets to 2P; 3P is used in three-phase equipment, there is a three-phase power into the home.

④ Is the lighting circuit with 1P or 1P+N?

Answer:

1. 1P for lighting, the traditional practice, there is nothing wrong with it. There is also 1P + N, think it is not necessary. Lighting without leakage. 2.

2. in fact, with 1P + N good, like DPN this switch, and 1P switch modulus the same! 

3. lighting generally with 1P, residential code mentioned residential bathroom lighting should be with leakage protection, so the bathroom lighting circuit available 1P + N with leakage protection.

⑤ residential single-phase distribution box into the line should be 1P or 2P?

 (Civil residential buildings, from the meter box out to the indoor distribution box for single-phase out, why the distribution box into the line with 2P instead of 1P it?)

Answer.

1. 2P, easy maintenance, safety!

2. When each residential single-phase power supply, the incoming miniature circuit breaker should be two-pole; when using three-phase power supply, the incoming miniature circuit breaker should be three-pole. And a self-repeating over- and under-voltage protector should be set.

① What is the difference between 1P, 1P+N and 2P mini circuit breakers?

Answer:

For miniature circuit breakers, 1P + N, 1P, 2P are generally used as a single-phase appliances on and off control, but the effect is different.

1P------ single-pole circuit breaker with thermal magnetic release function, controlling only the fire line (phase line), modulus 18mm.

1P + N---- single-pole + N circuit breaker, while controlling the fire line, zero line, but only the fire line has a thermal magnetic decoupling function; module number is also 18mm.

2P ------ single-phase 2-pole circuit breaker, while controlling the fire line, zero line, and both have a thermal magnetic decoupling function, the modulus is 2 * 18mm = 36mm. 

 Therefore, the following conclusions can be drawn.

1, in order to reduce costs, with 1P can, but the upper circuit breaker must have a leakage release function, in order to prevent the fire, zero misalignment caused by accidents, must cut off the upper power supply.

2, to avoid the problem of 1 article when overhauling, available 1P + N (i.e. DPN).

3, with 2P reason: for the same 18mm module circuit breaker shell, the internal installation of 1P and 1P + N is a difference, the former in the short circuit accident state "limit breaking capacity" is certainly higher than the latter, after all, space is an important factor affecting the breaking capacity. Therefore, for more important, frequent maintenance and operation, prone to failure of the power circuit, it is best to use 2P (higher cost).

4, with 1P premise is that the lighting distribution box must have the function of leakage disconnect, at least into the line (or out of the upper level) to use leakage circuit breakers.

② detailed explanation of the circuit breaker 1P, 1P + N, 2P, 3P, 3P + N, 4P.

A: 1P, 2P, 3P, 4P is the number of poles, indicating the ability to segment a few lines. Now +N, are N line break, but the N line is not set off the device. Only the phase line break when the N line incidentally cut off. For example, 4P 16A circuit breaker, N line current if greater than 16A, or, say, greater than 20A, theoretically, the circuit breaker will trip. But the 3P + N circuit breakers, N line current 160A, will not trip. The premise is that the phase line current are not more than the rated value.

③ What appliances are in use for 1P, 2P and 3P? What is the difference between them?

A: 1P, 2P single-phase equipment, lighting can use 1P, sockets to 2P; 3P is used in three-phase equipment, there is a three-phase power into the home.

④ Is the lighting circuit with 1P or 1P+N?

Answer:

1. 1P for lighting, the traditional practice, there is nothing wrong with it. There is also 1P + N, think it is not necessary. Lighting without leakage. 2.

2. in fact, with 1P + N good, like DPN this switch, and 1P switch modulus the same! 

3. lighting generally with 1P, residential code mentioned residential bathroom lighting should be with leakage protection, so the bathroom lighting circuit available 1P + N with leakage protection.

⑤ residential single-phase distribution box into the line should be 1P or 2P?

 (Civil residential buildings, from the meter box out to the indoor distribution box for single-phase out, why the distribution box into the line with 2P instead of 1P it?)

Answer.

1. 2P, easy maintenance, safety!

2. When each residential single-phase power supply, the incoming miniature circuit breaker should be two-pole; when using three-phase power supply, the incoming miniature circuit breaker should be three-pole. And a self-repeating over- and under-voltage protector should be set.