Elevator energy-saving equipment suppliers remind you that in today's city with high-rise buildings, elevators are essential tools for office or residential areas. However, elevators require regular maintenance to maintain their normal and safe operation.
Elevator maintenance is mainly to maintain its normal operation. In case of emergency situations such as power outages, fires, etc., elevator emergency devices are needed to handle them.
Working principle of elevator emergency device
Power detection
When the external power grid is supplying power normally, the power detection circuit of the emergency device gives a normal signal for the AC input power supply. The battery pack of the device is automatically float charged through the charging circuit to maintain the rated working voltage. The charging circuit has protection functions such as overcharge discharge, overcurrent, and short circuit.
Emergency operation
When the elevator encounters a power outage and the elevator control system stops running, the DSP control system of the emergency device will immediately detect the elevator status and automatically activate emergency rescue. Firstly, K1A is engaged to cut off the power supply from the external power grid to the elevator control transformer and perform electrical interlocking. Next, check the safety, door locks, and maintenance circuits of the elevator, and supply power to the door area sensors to detect the leveling signal. If normal, start the current converter to supply power to the door control system (AC door machine, DC door machine, variable frequency door machine). The door opening motor MD obtains the required voltage and opens both the car door and the hall door simultaneously; If the elevator car is not in the level position, the normally open contact of the relay is closed, and the DC converter supplies power to the holding brake circuit. The holding brake is opened, and the voltage output from the three-phase inverter circuit is supplied to the traction machine through the normally open contact of K2A, pulling the elevator car in a certain direction. The elevator car stops at the level position. Stop outputting the three-phase inverter voltage and close the brake. After the car door and hall door are opened, the contacts of the emergency device's contactor and relay are all restored to the state before emergency operation.
Safe locking
If the DSP control system of the emergency device determines that the elevator has stopped running due to a fault in the safety circuit or door lock circuit, according to the requirements of the "Safety Regulations" for elevator operation, the device will not be put into emergency operation. Even after the emergency device is put into emergency operation, the signals of the elevator safety circuit and door lock circuit are always monitored. Once any protection signal is generated, the emergency operation will be immediately terminated to ensure the safety and reliability of passengers and elevator equipment. Similarly, the emergency device is constantly monitoring the maintenance circuit of the elevator control system. When maintenance personnel are inspecting the elevator, as long as the maintenance switch is pressed, the device will automatically lock and not be put into emergency operation.
Emergency end
After the emergency operation is completed, the connection between the device and various parts of the elevator control system is disconnected, and it is in an isolated standby state, which has no impact on the normal operation of the elevator. When the three-phase AC power supply is restored, the charging circuit of the emergency device will automatically recharge the battery pack.
Install multiple 'safety belts' for elevators. Many developers and property management departments have been lacking necessary investment and attention to the issue of reliable power supply for elevators. Due to power shortages, some lines in the main urban area may still experience emergency local short-term power restrictions. In addition, various external forces may also cause local power outages. If the elevator is equipped with an emergency power supply, it can ensure the normal operation of the elevator in case of an emergency power outage, facilitating the safe transfer of passengers.