How to draw a circuit in which two switches control a light?

Step: 1. Open the cover of the single-pole double-throw switch and find out the communication relationship between three terminals (or three screws) and the flying knife: one terminal is connected with the flying knife A through the rotating shaft, and the other two are connected with independent contacts respectively.

Fig. 1 is a schematic diagram of the single-pole double-throw switch, where 1 represents the terminal connected with the flying knife A through the rotating shaft, and 2 and 3 represent the terminals connected with independent contacts; The figure shows that 1 is connected with 2. Turn the shaft once (that is, pull the cable once), and it will be changed to 1 and 3.

2. Circuit design of stair lamp: Design the experiment with the help of the teacher.

Analyze whether the circuit diagrams in Figure 2, Figure 3 and Figure 4 conform to the principle of safe electricity use. Which of these connections is wrong?

3. Install according to the requirements of circuit installation process and cleanliness and beauty.

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