What Does The Elevator Safety Circuit Include?

1. In the machine room: safety circuit power circuit breaker (control cabinet fuse or circuit breaker), speed limiter switch (machine room), phase sequence switch (phase sequence), disc wheel switch (traction machine), machine room emergency stop (machine room maintenance box, traction machine side), steel strip switch (not available in new elevators, generally stored in OTIS old elevators).

2. On the car roof: safety clamp switch (under the car crossbeam), door motor switch (door

Next to the machine control box, emergency stop of the maintenance box (car roof maintenance box), safety window switch (safety window).

3. In the pit: car buffer switch (S1), counterweight buffer switch (S2), speed limiter rope breaking switch (rope pulley switch), high-level emergency stop (next to the ladder), pit emergency stop (pit maintenance box).

4. Within the shaft: upper limit (upper station of the shaft), lower limit (lower station of the shaft). The safety circuit voltage is generally AC110V, and some elevators are different, which can be marked in the electrical schematic diagram. The safety circuit voltage cannot be too high or too low. For the convenience of us to quickly determine which switch has activated, it can also be inferred from elevator malfunction phenomena. Generally, when an elevator passes through the top floor position by more than 150mm, it can be judged as pressing the upper limit switch and counterweight buffer switch, which is called "hitting the top". If the elevator passes through the lower floor position by more than 150mm, it can be judged as pressing the lower limit switch and car buffer switch, which is called "squatting at the bottom". If the elevator stops at the middle floor and the safety circuit is disconnected, the speed limiter switch, safety gear switch, and rope pulley switch can be checked. After we finish repairing the elevator, we must remember to restore the emergency stop button that has been operated.