Product Code: 091-171-12


  • 20A, 12V charge rating
  • System consists of the Add-A-Bat Charger, Triple Bar Graph Display and Solenoid
  • Add a battery to any vehicle to power accessories
  • Automatic battery charger to maintain both auxiliary and main batteries
  • Automatically parallels batteries when engine is running
  • When the engine is stopped or charge voltage is no longer present, the solenoid opens to isolate the batteries
  • Bar graph display indicates battery voltage and charger output current
  • All accessories may be connected to auxiliary battery 
  • 3 year warranty
Charger, Output Amperage 33
Charger, Output Voltage VDC 12
Charger, Input Voltage VAC 120
Charger- Hz 50/60
Charging Profile float
Input Fuse 8 Amps, Fast Acting
Input 120 Vac, 50/60 Hz, 4.7 Amp Max
Output 12 Vdc, 20 Amps
Output Fuse 40 Amps
Warranty 3 years
Charge Indicator 0-25 Amps

Volts : 12 Vdc

Coil Current : .45 Amps

Contact Rating : 200 Amps Continuous, 600 Amps Surge

Weight : 2 lbs

Warranty : 3 Years

Often, in many vehicles when numerous accessories are added, it is desirable to add an additional battery. The Add-A-Bat, Model 091-171, simplifies this installation and provides a battery charger for the vehicle's battery as well as the newly installed auxiliary battery. The accessories are connected to the auxiliary battery and thus reduces the burden on the vehicle's battery. A high current solenoid connects the two batteries whenever the alternator output is detected. This charges both batteries when the engine is running. An Auto Boost feature parallels the batteries for engine cranking whenever the auxiliary battery has sufficient charge. The triple bar graph display indicates the voltage of each battery, and the charger output current whenever the vehicle is plugged into AC shore power.