Introduction:
The RMU Battery Charger (24V) is specifically designed for switchgear units, ensuring uninterrupted power supply to switchgear motors. It operates through three power sources:
- Charger 1
- Charger 2
- 24V Battery
The system ensures seamless power transition and bumpless switching between power sources. Both charger outputs are combined using a blocking diode, and power is distributed through a Controller Card. If Charger 1 fails, Charger 2 automatically takes over. In the event of mains failure or both chargers failing, the battery supplies power to the entire load, ensuring continuous operation.
System Components:
- Redundant Battery Chargers
- 24V Battery
- Controller Card
Technical Specifications
- Battery Voltage: 24 VDC
- Battery Capacity: 12 Ah (at 20-hour discharge rate)
- Battery Charger Module Rating: 10A continuous per charger (Two 5A power supplies in parallel)
- Battery Charging Type: Constant Current (CC) & Constant Voltage (CV)
- Battery Charger Cooling: Natural air cooling with ventilation louvers on the metal enclosure
- Battery Charger Output Regulation: ±2%
- Battery Charger Output Ripple: 1% RMS
- AC Input Power: 170 – 285 VAC, Single Phase, 50Hz ±5%
- Built-in Charger Protections:
- Output Overload Protection
- Output Short Circuit Protection
- Input Overvoltage Protection (above 320V RMS for short duration)
- Input Short Circuit Level: 10 KA
- Input Insulation Withstand: 1500 VAC for 1 minute
- Input Insulation Resistance: Minimum 10MΩ (measured with 500 VDC Megger)
- Cable Termination: Pluggable type, supports up to 2.5mm² wire
- Remote Indication Relay Outputs:
- Battery Low / MCU Faulty (Potential Free Contact)
- Charger 1 Fail (Potential Free Contact)
- Charger 2 Fail (Potential Free Contact)
Visual Indications on the Front Panel
- MCU Faulty (Red LED): Blinks when the controller malfunctions or gets stuck.
- Charger 1 Fail (Red LED): Glows when Charger 1 output fails or drops below the threshold.
- Charger 2 Fail (Red LED): Glows when Charger 2 output fails or drops below the threshold.
- Battery Low/Battery Reverse (Red LED): Glows when battery voltage is below the threshold, the battery is disconnected, or connected in reverse.
- Mains ON (Green LED): Glows as long as AC input power is available.
- Battery Reverse (Red LED): Glows on the Controller Card when the battery is connected in reverse.