How to prevent data acquisition from being interrupted when the concentrator voltage drops?

The concentrator should maintain uninterrupted data acquisition and prevent data loss during short-term voltage drops or interruptions in the mains power supply (IEC 61000-4-11). This requires the power supply system to have sufficient hold-up time and rapid switching capability. The large-capacity energy storage capacitor at the main power input needs to have its hold-up time calculated. For example, under full-load power P, the capacitor C must satisfy C > (2 * P * t) / (V1^2 - V2^2), where t is the hold-up time (e.g., 20ms), V1 is the normal voltage, and V2 is the minimum operating voltage. A wide-input-range switching power supply module (e.g., 85-265VAC) should be used. Critical circuits (MCU, memory chips) are powered by backup batteries or supercapacitors, automatically switching in case of main power failure. In terms of software, upon detecting a voltage drop, critical data is immediately saved to non-volatile memory (e.g., FRAM) and a low-power mode is entered; data is restored in an orderly manner after the voltage recovers. Through design, the concentrator can withstand a 100% voltage drop for 0.5 cycles without interrupting data acquisition.