Batteries: The hazards of UPS starting and shutting down under load

　　UPS battery power supplies have the minimum battery voltage maintenance value, but the relationship between the terminal voltage and the discharge current is close, the lower the discharge current, the higher the terminal voltage, the more practical capacity is released when the minimum maintenance value is reached . Therefore, the UPS operating at light load should try to avoid the appearance of shutting down after the discharge reaches the minimum maintenance value. For long-delay UPS, the maintenance value of the lower limit voltage of discharge should be increased appropriately.

　　④UPS is not suitable for starting up and shutting down under load

　　 There is no delay in starting the function of the UPS. Simply burn the final drive components of the inverter at the moment of starting. Since the operation of the control circuit has not yet entered a stable state when it is just opened, a relatively large surge current will be generated at the moment of starting, and the final drive components may not be able to withstand it. This is especially true for UPS that selects MOS tubes as driving components. When the load contains an electrical load, shutdown on load can also cause damage to the final drive components. Therefore, it is not an emergency, do not start and shut down with load.

　　⑤When the UPS inverter is operating normally, stop using an oscilloscope to investigate the waveform of the control circuit

　　The core component of the UPS power supply is the inverter When the inverter and inverter are running, please do not use oscilloscope and other test tools to investigate the waveform of the control circuit. Because of the extra care during the test, it is difficult to avoid the test leads from colliding with the proximity point, and it is even more difficult to avoid the change in the circuit operation status after the test leads are connected. Once the circuit operation is abnormal, there is a danger of burning down the final drive components. During the repair, we have found the appearance of artificially burning the inverter repeatedly. Some are due to lack of repair experience, and some are for learning and investigating circuit waveforms.