XH-M609 Battery Undervoltage Protection 6-60V

Product detailed description

The XH-M609 module is a protection circuit that reliably protects your battery from deep discharge. It continuously monitors the battery voltage and disconnects the load via a relay output as soon as it drops below the set value. Once the battery is charged above the set level (cutoff voltage + hysteresis), it automatically reconnects the load. You can set the cutoff voltage, hysteresis and relay delay using two buttons in 0.1 V increments, while the current battery voltage is clearly shown on a three-digit LED display. Thanks to its wide DC 6–60 V power range, the module is suitable for off-grid photovoltaic systems, caravans, motorhomes, boats, backup power sources and general DIY projects.

Specifications:

• Type: load disconnecter / battery deep discharge protection
• Operating voltage: DC 6–60 V (suitable for 12V, 24V, 36V and 48V systems)
• Voltage measurement:
  • Accuracy: ±0.1 V
  • Setting step: 0.1 V
• Display: three-digit LED, shows current battery voltage
• Output: relay, switching contact (NO)
• Max. relay load: 10 A
• Module Power Consumption: less than 1.5 W
• Settings Memory: yes, values are retained after power disconnection
• Connection: screw terminal block (VIN – battery, VOUT – load)
• Dimensions: 57 × 42 × 19 mm
• Weight: approx. 28 g
• Adjustable parameters:
  • Cut-off Voltage: double press of the “+” button
  • Hysteresis (reconnection voltage): double press of the “−” button
  • Relay Delay: long press of the “−” button
  • Voltmeter Calibration: long press of the “+” button
• Settings Check:
  • Short press “+”: displays the set cut-off voltage
  • Short press “−”: displays the set hysteresis
• Suitable for batteries: lead-acid (AGM, gel, traction), LiFePO4 and Li-Ion (set values according to cell chemistry)

Setting Example:

• Cut-off voltage 11.0 V and hysteresis 0.5 V — the relay disconnects the load at 11.0 V and reconnects it once the battery voltage rises to 11.5 V.

Package contents:

• 1× XH-M609 battery protection module

Note:

• Set the cut-off voltage according to the type and chemistry of your battery — for lead-acid batteries, we do not recommend going below approx. 11.5 V (12V system); for LiFePO4, follow the cell manufacturer's recommendations.
• Ensure correct connection polarity and make sure the load current does not exceed the relay's rated capacity. The stated value applies to AC voltage — for DC loads, especially at higher voltages, leave sufficient headroom. For inductive loads (motors, pumps), account for a higher starting current.
• The module disconnects the load; it does not replace a fuse or a solar charge controller.
• This product is not a standalone functional unit and may require professional installation.
• Product images are for illustrative purposes only and may sometimes differ from the actual appearance of the item. However, this does not change its basic properties.