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1. The hazards of voltage sags and the necessity of addressing them Voltage sags are random, unplanned power supply failures that act as \"invisible killers\" that disrupt the continuity and reliability of power supply. They are usually caused by lightning strikes, heavy fog, short circuits, or the startup of heavy loads. When a voltage sag occurs, it leads to a temporary drop in grid voltage; if this drop lasts for too long or is severe enough, it can cause sensitive equipment to trigger alarms or shut down. The extent to which sensitive loads can tolerate such voltage drops needs to be determined based on the specific conditions at the site. Factors to consider include mathematical models of voltage drops, the operating status of the grid’s load, and the specifics of each voltage sag incident. Production disruptions caused by voltage sags not only result in reduced output but also affect product quality, leading to significant financial losses and negative impacts on a company’s profitability. Given the objective hazards posed by power surges, continuous manufacturing industries such as those in petrochemicals, coal mining, biopharmaceuticals, semiconductor manufacturing, and new energy sectors need to implement appropriate measures to address these power surge issues, in order to avoid economic losses and safety risks. Such measures are necessary to ensure the continuity and stability of production processes. Here, we introduce an economical and convenient two-in-one power surge protection module. Some companies choose permanent-magnet AC contactors in order to ensure that the motor control circuit does not release under voltage fluctuations; by engaging after a delay, such contactors help to keep the control circuit active. However, this approach has many disadvantages. Firstly, permanent-magnet AC contactors are relatively expensive, which hinders their widespread use ； Secondly, this type of permanent-magnet AC contactor is unable to intelligently identify different scenarios such as voltage fluctuations, shutdowns, or equipment failures; it may also experience delayed responses during normal shutdowns. Then, during a voltage fluctuation, the line voltage becomes unstable. At this time, the contactor remains in the energized state, resulting in an unstable voltage being applied to the motor. This low voltage may cause the motor to burn out. Finally, when the voltage fluctuation ends and the voltage returns to normal, the speed of many motors has already decreased significantly or they have come to a halt. If these motors are restarted simultaneously at this point, it will impose a severe burden on the power distribution system. 2. Governance solution configuration: The DCM621KH intelligent motor vibration prevention device integrates advanced power electronics, curve fitting, and synchronous starting technologies. It employs unique detection methods and logical judgments to monitor the grid voltage and the operating status of contactors in real time. When a power fluctuation occurs, the device is powered by an internal supercapacitor to maintain normal operation; if the duration of such fluctuation is less than 500 mS, the device outputs power through its internal contacts to keep the motor control circuit functioning ； If the flicker time is greater than 500 mS and the contactor has been released, once the device detects that the voltage has returned to normal, it automatically enters the \"synchronous restart\" mode. The restart functions of DCM621KH are divided into two types: immediate restart upon voltage drop and staged simultaneous restart upon voltage drop. By setting a predetermined restart delay time, immediate restart in the event of under-voltage or staged simultaneous restarts can be achieved, enabling the motor to start safely and quickly and restoring the production process. The DCM621KH can automatically adapt to various contactors and control circuits without the need to consider motor capacity. Both the flicker tolerance time and the restart delay time can be set by rotating the DIP switch, which is highly user-friendly and very simple and convenient. For motors with different starting methods, there are corresponding specific models, and the typical wiring methods and working principles are described as follows. 1) Direct-start type: file:///C:/Users/MARKET~1/AppData/Local/Temp/ksohtml816/wps18.jpg. Working principle: When the motor is started manually or remotely, the KM coil is powered by external alternating current; once energized, the KM coil causes its normally open contacts to close, allowing power to be maintained through these contacts. When the device detects that the working power supply, the contactor coil voltage, and the control circuit voltage are above the set voltage levels, it begins charging; once 5 seconds of charging have elapsed, it enters the anti-vibration standby mode. During operation, if the device detects that the operating power supply, the voltage of the contactor coil, and the voltage in the control circuit are all below the set value corresponding to no voltage, it determines that a voltage fluctuation has occurred. In such cases, the supercapacitor built into the device is activated automatically to provide stable power to the electrical modules, preventing disruptions caused by voltage fluctuations. The system then starts timing; if the duration of the voltage fluctuation is less than 500 ms, the device maintains its normal operation through its internal circuits. If the voltage fluctuation lasts more than 500 ms and the contactor has released, the device detects that the voltage of the control supply has returned to normal and automatically enters restart mode. It offers two options: immediate restart or delayed restart, allowing for rapid startup of the motor and resumption of the manufacturing process. If the device detects that the operating power supply is normal, but the voltage of the contactor coil and the voltage in the control circuit are below the no-voltage threshold, it is determined as a manual stop; the shock protection module discharges automatically, and the shock prevention function is deactivated automatically. 2) Soft-start type: file:///C:/Users/MARKET~1/AppData/Local/Temp/ksohtml816/wps19.jpg. Working principle: When the soft-start device is started manually or remotely (via the RUN signal), once the motor reaches its rated speed, the starting process is completed. The K1 node inside the soft-start device closes, and control is transferred to the bypass contactor to complete the starting process; at this point, the coil of the bypass contactor KM is powered by external alternating current and remains active. When the device detects that K1 is closed, it starts charging; after 5 seconds of charging, it enters the anti-vibration standby mode. During equipment operation, if the device detects that the voltage of the operating power supply and the contactor coil is below the set value corresponding to no voltage, it determines that a voltage fluctuation has occurred. At this point, the supercapacitor inside the device is activated automatically to provide stable power to the electrical modules, preventing such fluctuations. The system then starts timing; if power is restored automatically within the set maximum time for voltage fluctuations, the delay device causes the RT output to close, thereby restarting the soft-starting equipment. The restart process is completed once K1 closes. After startup is complete, if the device detects that the operating power supply is normal and the coil voltage is below the no-voltage threshold, it is determined as a manual stop; the shock protection module discharges automatically, and the shock prevention function is deactivated automatically. 3) Variable-frequency start type: file:///C:/Users/MARKET~1/AppData/Local/Temp/ksohtml816/wps20.jpg. During normal operation, when the frequency converter is started manually or remotely, the KA coil is powered by external alternating current. Once energized, the KA coil acts to close its normally open contacts; the power supply is thus maintained through these closed contacts, while the other set of KA normally closed contacts opens. The closing of the KA normally open contacts enables the start of the frequency converter. When the device detects that the working power supply, the voltage of the KA coil, and the voltage of the control circuit are above the set values corresponding to an energized state, it begins charging; once 5 seconds of charging have elapsed, it enters the anti-vibration standby mode. During operation of the equipment, if the device detects that the supply voltage, the voltage of the KA coil, and the voltage in the control circuit are below the set value corresponding to no voltage, it determines that a power fluctuation has occurred. At this point, the supercapacitor built into the device is activated to provide stable power to the relevant electrical modules. The system then starts timing; if power is restored automatically within the specified maximum time for such fluctuations, the RE output of the device closes, thereby resetting the fault signal related to the inverter. After a delay, the RS output closes, automatically restarting the KA relay, which in turn starts the inverter and restores normal operation to the conditions prior to the power fluctuation. If the device detects that the operating power supply is normal, but the voltage of the contactor coil and the voltage in the control circuit are below the no-voltage threshold, it is determined as a manual stop, and the anti-vibration function is automatically deactivated.