The full name of the DC power screen is intelligent high-frequency switching DC operation power screen. It is the core emergency and control power device for power supply systems in substations, distribution rooms, industrial and mining enterprises, high-rise buildings, etc. It mainly provides uninterrupted and highly reliable DC power for high-voltage switch closing and opening, relay protection, automatic devices, emergency lighting, etc., and is a key equipment for ensuring the safe and stable operation of the power grid.

I. Product Application
1. Provide DC power for closing and opening operations of high-voltage circuit breakers and load switches
2. Supply control power for relay protection, measurement and control devices, and automatic control systems
3. Provide emergency lighting and backup power during power outages of AC power
4. Provide stable DC power for signal systems, monitoring systems, and communication devices
5. Ensure reliable operation of protection devices and normal opening of switches in case of faults

II. System Composition
The standard DC power supply is mainly composed of the following units:
1. Dual AC input unit with automatic switching between 380V and 220V to ensure uninterrupted power supply.
2. High-frequency switching charging module converts AC power into DC power, achieving stable voltage and current output, and performing floating charge and equalization charge management for the batteries.
3. The battery pack mostly uses maintenance-free lead-acid batteries, which continue to discharge in the event of an AC power outage, ensuring the system remains powered.
4. Central monitoring unit displays voltage, current, battery status, and fault information in real time, and automatically manages the charging and discharging process.
5. DC feed unit provides multiple DC outputs, supplying control, protection, signal, closing, etc. circuits respectively.
6. Insulation monitoring device detects the insulation of the DC system to ground in real time, and gives an alarm promptly in case of grounding faults.
7. Battery inspection unit online monitors the voltage and temperature of each battery, enabling early detection of battery deterioration and faults.
8. Voltage reduction silicon chain / voltage regulation device stably controls the bus voltage to ensure the reliable operation of protection devices.

III. Working Principle
Normal operation: AC mains power supply → Charging module operates → Supplies power to DC loads simultaneously + Float charges the battery.
AC power failure: The battery automatically takes over power supply to ensure uninterrupted control, protection, and closing/opening of switches.
Power restoration: The system automatically switches back to the float charging mode and charges the battery to replenish its energy.

IV. Main Technical Parameters
Rated DC Voltage: DC 220V / DC 110V / DC 48V
System Capacity: 20Ah, 40Ah, 65Ah, 100Ah, 200Ah, etc.
AC Input: AC 380V/220V 50Hz
Stabilization Accuracy: ≤±0.5%
Ripple Coefficient: ≤0.5%
Equipped with overvoltage, undervoltage, overcurrent, short circuit, and battery overcharge/overdischarge protection
Support RS485/Modbus communication, and can be connected to the background monitoring system

V. Product Features
1. High Reliability: Dual AC input, redundant design of charging module, no power outage in case of failure
2. High Degree of Intelligence: Fully automatic floating charge / equalization charge, unmanned operation
3. Comprehensive Protection: Comprehensive electrical protection, fault sound and light alarm, remote upload
4. Safe Operation: Insulation monitoring, battery inspection, preventing DC grounding and battery failure
5. Compact Structure: Integrated cabinet design, easy installation, low maintenance requirements
6. Wide Applicability: Can be used in indoor distribution rooms, box-type substations, switchgear stations, etc.

VI. Application Scope
It is widely applicable to:
10kV/35kV substations, ring-main units, switchgear stations
European-style box-type transformers, general substation facilities of industrial and mining enterprises
Power plants, hydropower stations, water conservancy hubs
Hospitals, data centers, high-rise buildings, rail transit, petrochemical plants, etc.