The functions of ARD

The ARD in the elevator is an automatic rescue device, also known as an elevator emergency rescue device or an elevator emergency power supply. Its main function is to automatically start and provide emergency power to the elevator control system when the elevator fails (such as power outages, line failures, etc.), so that the elevator can slowly run to the leveling position and open the door to release passengers.

Specifically, the functions of ARD include:

1. Emergency power supply function

When the power supply of the power grid is normal, ARD is in standby charging state; after the power grid is off, ARD automatically enters the inverter state to provide three-phase or two-phase emergency power to the elevator control system.

2. Automatic leveling function

Driven by the emergency power supply, the elevator car will slowly run to the nearest leveling position. The direction of the elevator's operation depends on which direction requires the least power when moving the car to the floor door. After reaching the nearest floor, the elevator door will automatically open so that passengers can leave safely.

3. Fault detection and signal transmission

ARD can detect the interruption of the elevator drive input phase caused by power grid failure or line failure, and send a fault signal to the elevator controller. After receiving the signal, the controller will release the motor-driven brake to move the elevator car to the nearest door.

4. Avoid secondary injuries

After the elevator stops unexpectedly due to a fault, the activation of ARD can prevent passengers from being trapped in the car for a long time, reducing physical and psychological damage to passengers.

5. Provide safety instructions

During the emergency process, ARD will play a voice to comfort the trapped passengers, and the audio or video indicator light in the elevator will indicate that the passengers can leave the elevator safely.

6. Restore standby state

After the grid power is restored, ARD will automatically return to the standby charging state so that it can be put into use in time when the next fault occurs.

In addition, ARD has the characteristics of simple installation and wiring, convenient debugging, and high cost performance, and is suitable for various domestic or imported elevators. The battery pack usually uses maintenance-free batteries, and the charging method is pulse charging, which can not only shorten the time to fully charge, but also reduce the polarization of the positive and negative electrodes of the battery, and improve the battery efficiency.