01. Which P should I choose? Answer: 1P is a single switch that only cuts off the live wire, usually used for lighting or electrical equipment with low power consumption; 2P is double open, with two input (output) line segments, the live wire and the neutral wire, which are commonly used; 3P is a three-way switch that controls three-phase electricity, with three input (output) terminals and three live wires. It is usually used for three-phase electrical bus switches and three-phase electrical equipment; 4P is the addition of one terminal on top of the three open, represented by the neutral terminal N. 02. How to choose the current for household use? Answer: The circuit breaker needs to be matched with the power of the wires and electrical appliances, otherwise it is prone to tripping, burning of the terminals, and other situations. You can refer to Table 1 and Table 2 for selection, and the specific requirements shall prevail.