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Soneil 12v 3 Amp Constant Current World Smart Charger Son1205SR

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Product InformationStore Part Number: Son1205SR


Protection provided: Reverse Polarity, Short Circuit, Over-Voltage, Over Current and AC Surge. Soft Start and Stop = starts and stops gradually. No sudden in-rush of current; this protects both the batteries and any other circuits connected to the charger.

Soneil’s Battery Charger transforms the 115/230 VAC into 12 VDC at about 100,000 Hz (1667 times faster than conventional charger), which requires a much smaller transformer. This results in a unit of smaller size, low weight, and improved efficiency. The 1205SR uses sophisticated electronic circuitry with microchips. All present day computers use switch-mode technology.

  • Two Color LED

  • Red indicates power is on

  • Yellow batteries are in charge mode

  • Green batteries are charged and batteries are at float

  • Green flashing output not connected


Stage 1: Deep Discharge Charging Pulse Mode
The Charger starts charging at 0.5 V and give pulse current up to 5 V. This has effect of removing loose sulphation formed during deep discharge state of the battery.

Stage 2: Constant Current Mode (CC)
The charger changes to constant current 3.0 A. When the battery voltage reaches up to 14.4 V, the charging stage changes from (CC) Constant Current to CV (Constant Voltage) mode.

Stage 3: Constant Voltage Mode (CV)
The charger holds the battery at 14.4 V and the current slowly reduces. When the current reaches at 0.5 C (C= Battery Capacity), this point called the Switching Point. The Switching Point is one of the great features of this battery charger. It can adjust the current automatically according to the battery capacity. Other chargers without microprocessors are not capable to adjust the current automatically.

Stage 4: Standby Voltage Mode
The charger maintains the battery voltage at 13.8 V and current slowly reduces to zero. Charger can be left connected indefinitely without harming the battery.

If the battery voltage drops to 12.5 V , the charger changes from any mode to Constant Current mode and restart charging. The charging cycle will go through Stage 2 to Stage 4.

This charger typically ships with without output connectors, allowing customer to adapt the charger to their specific needs.


  • Totally Automatic Switch-Mode Battery Charger
  • Suitable for Gel, Sealed (AGM) and Wet Lead Acid Batteries
  • Suitable for use anywhere in the world
  • Dual Voltage-Switch selectable 115/230 VAC 47 to 62 HZ
  • Automatic Cutoff and then True Float. Can be left connected indefinitely without harming the battery.
  • Two color LED to indicate charge status
  • Mean Time between failures 30,000 hours
  • Zero Current Drain when AC power is off
  • Very low start voltage 0.5 V
  • Optimal 3 Step Charging
  • Built-in Mode Indicators
  • Demand Sensing
  • Reverse Polarity Protection
  • Over Voltage Protected
  • Short Circuit Protection
  • Overload Protection
  • Thermal Protection
  • 2 Year Warranty

Tech Specs

  • Dimensions (LxWxH): 6 x 3.7 x 1.9 in
  • Weight: 1.5 lb
  • Shipping Weight: 3.0 lb
  • Max Current, During Bulk Charge: 3 A
  • Absorption Voltage: 14.4 V
  • AC Input Volts: 115/230 V
  • Manufacturer: Soneil
  • AC Input Volts Freq.: 47/63 Hz
  • AC Input Volts Range: 90–260 V
  • Float Voltage: 13.8 V
  • Charge Reset: Battery Voltage Threshold: 12.5 V
  • Output Banks: 1
  • Regulatory Approval: UL, CSA, CE, TUV, and GS Listed
  • Manufacturer Part #: Son1205SR

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