XH-M350 12V 5A Automatic Battery Backup Switching Module DC UPS Relay Board

🔧 XH-M350 12V 5A Automatic Battery Backup Switching Module | AuscomTech

The XH-M350 is a compact 12V DC automatic power changeover board designed to switch a connected load between a primary power adapter and a backup battery when the main supply is interrupted.

During normal operation, the module prioritises the primary power supply and illuminates its green LED indicator. When primary power is lost, the onboard relay automatically transfers the load to the backup battery, activating the red indicator. Power is automatically returned to the primary adapter when it becomes available again.

Designed for emergency DC power systems, security equipment, lighting and electronics projects, this standalone board offers convenient automatic source selection without programming or external controllers.

⭐ Key Features

• Automatic Battery Changeover – Transfers between a primary 12V supply and a connected backup battery when the main power source fails or returns.
• 5A Documented Control Current – Supplier documentation specifies a 5A control current for low-voltage DC load switching.
• Primary Power Priority – Uses adapter power whenever it is available, conserving backup battery capacity.
• Relay-Controlled Transfer – Onboard electromechanical switching provides automatic operation without manual intervention.
• Dual LED Indicators – Green indicates primary supply operation; red indicates battery backup operation.
• Separate Power Inputs – Dedicated terminals for the DC adapter and battery, plus a common switched output.
• Automatic Return to Main Supply – Restores adapter-powered operation after the primary supply returns.
• Compact PCB – Measures approximately 54 × 26.3mm for integration into electronic enclosures.
• No Programming Required – Operates independently of Arduino, ESP32 or other microcontrollers.

📊 Technical Specifications

• Model: XH-M350
• Module Type: Automatic DC Battery Backup Changeover
• Nominal Operating Voltage: 12V DC
• Documented Control Current: 5A
• Advertised Power: 150W (supplier claim; not verified at 12V/5A)
• Calculated Power at 12V / 5A: 60W
• Switching Component: Electromechanical Relay
• Primary Input: 12V DC Power Supply
• Secondary Input: 12V Battery
• Output: Automatic Switched DC Output
• Connection Type: Screw Terminals
• Status LEDs: Green / Red
• Board Dimensions: 54 × 26.3mm
• Weight: Approximately 25.9g
• Control Method: Standalone Automatic Switching

🧩 Typical Applications

• 12V DC battery backup systems
• Emergency lighting controllers
• Security alarms and monitoring circuits
• Low-voltage communications equipment
• Router and network device backup arrangements
• Automation panels and control systems
• DIY solar and battery power source selection
• Arduino and ESP32 installations with suitable DC power regulation
• Automatic power failure changeover projects

⚠️ Important Notes

• Rating Clarification: Supplier material lists 5A control current and 150W supported power. At 12V, 5A equals 60W; therefore, the 150W claim cannot be confirmed as a continuous 12V output rating. The separate 12A claim is also unverified. The listing uses the documented 5A specification rather than advertising an unsupported 12A rating.
• Not a True Zero-Interruption UPS: The onboard relay takes time to change contacts. Sensitive electronics may reset during the transition.
• No Charging Function: Does not automatically charge the backup battery. Use a suitable separate charger or battery management system.
• DC Operation: Designed for nominal 12V DC circuits. Do not connect mains AC voltage to the module input or output terminals.
• Correct Wiring Required: Check positive and negative terminal markings before connecting the primary supply, battery and load.
• Battery Protection: Provide suitable overcurrent protection and battery low-voltage protection where required.
• External Equipment: Power supply, battery, charger and wiring are not included.

📦 Package Includes

• 1 × XH-M350 12V 5A Automatic Battery Switching Module

🔗 Recommended Accessories (Not Included)

• 12V DC Regulated Power Adapter – Primary power source for normal operation.
• 12V Backup Battery – Secondary supply during primary power failure.
• Compatible Battery Charger / Protection Module – Provides charging and battery protection functions.
• DC Wiring and Inline Fuse – Provides suitable connections and circuit protection.