Model SF 503B

Battery Back Up
For Alternative Heating Appliances

800 Watt Capacity

SF 503B interfaces between a heating appliance (wood pellet or alternative fuel stove) and its AC wall outlet. When AC utility power is present, the SF 503B charges a battery and monitors the wall outlet to detect a power outage. At the moment utility power fails, the SF 503B draws energy from a battery and converts it to enable appliance operation. When utility power returns, the SF 503B automatically switches the appliance back to AC wall outlet power. At the same time, the SF 503B resumes charging the battery to return it to full capacity in preparation for the next power failure.

General Application

  • To determine compatibility: User should verify that under no conditions does the heating appliance draw more than 7A from the AC outlet


  • Rugged Aluminum Housing
  • Battery Cables Included
  • Works with Common Marine Batteries
  • Compact Size
  • For Wall Mount or Surface Mount Installation
  • 2 year Factory Warranty


  • Works with Most Alternative Fuel Devices
  • Instant Automatic Power Transfer
  • Supports Full Stove Electrical Capacity
  • Does Not Occupy Living Quarter Space
  • Can Be Easily Installed
  • Silent and Clean Operation


  • Wood Pellet Stoves
  • Kerosene Heaters
  • Gas Stoves
  • Corn Stoves
  • Multi Fuel Stoves