What should be noted when checking the brake coil control circuit?

Through the study of the standard and the experience of the actual combat, the following aspects should be paid attention to when checking the brake coil control circuit.

(1) Carefully check the electrical schematic diagram and wiring diagram, and carefully analyze the number and mutual independence of electrical devices in the control circuit. It can be seen that XC, SC and YXC are not independent, but mutually controlling relationships.

(2) Check the control circuit of the brake to see if two or more electrical devices cut off the brake current.

(3) Analysis of the independence between the electrical devices that cut off the braking current. After confirming that the number of electrical devices that cut off the brake current exceeds two, it is necessary to further analyze the independence between the electrical devices.

(4) The electrical structure can also be inspected on site after the review. In general, follow these steps:

First, confirm whether the equipment and drawings are consistent, confirm whether the equipment and drawings are consistent, and then complete the inspection of the problems left in the drawings, such as the number and style of electrical equipment.

Turn on the power of the elevator, put the car in the middle layer station, and close the elevator door.

When the elevator is running, the machine room mechanic uses a tool to hold down the contactor that has been sucked in to cut off the brake current.

Elevator flat floor parking. At this time, the tested contactor acts on artificial external force, and the main contact should be closed to simulate the electric shock adhesion state. The maintenance personnel in the kiln re-select the original starting floor, and the elevator will not work.

When carrying out the above test, people should be placed next to the main power supply. In case of any accident, the power failure should be stopped immediately.

During the above experiment, if the running direction of the elevator changes, the elevator cannot work, and it can be judged that the brake electrical control system meets the standard, thereby confirming that the experimental conclusion is qualified.

What is the new role of the brake?

For the elevator, the brake is both a working device and a safety device. With the development of technology and the improvement of energy saving and environmental requirements, more and more permanent magnet synchronous gearless tractors have replaced the traditional worm gear traction machine, so it may no longer need to install a separate upstream overspeed protection device. The brake of this permanent magnet synchronous gearless traction machine (type test) has an upward overspeed protection function. According to the requirements of Article 9.10 of GB 7588-2003, the upstream overspeed protection device of the automobile is generally composed of two parts: the speed monitoring element and the deceleration actuator. The brakes of permanent magnet synchronous gearless tractors (all brake components that apply force to brake wheels or discs are considered to have internal redundancy) are to slow down or stop the elevator as a deceleration actuator. Therefore, in the inspection, the brake has a style test certificate and report with an upward overspeed protection function, whether there is a direct rigid connection between the brake and the traction wheel, and there is an electrical device to confirm whether the brake is working normally. But do not enter the safety loop. The braking performance for overspeed protection also meets the relevant requirements of Article 9.10 of GB 7588- 2003. TSG T700 -2009 requires the elevator manufacturer to provide the drive host type test certificate, and at the same time reviews some drive host type test verification certificates and reports. Including the brake content.