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Dual Battery Kit with Smart Isolator Relay for Auto/Boat/RV

Price: $149.95
Weight:  5.00lbs
In stock
This is a great kit for adding that 2nd or 3rd battery to your system in your car, boat, RV or whatever you wish. It utilizes the simplest and most advanced technology to keep all your batteries charged using the engine’s electrical system but isolating the starting battery so you never get stranded. The great thing about these is that you don’t have to reroute any alternator wires and they are fully automatic. Everything you need to do the job yourself.

  • Suitable for 12V Marine, Off-Road Vehicles, RV, 12V Auto & Solar Systems
  • 140 Amp Voltage Sensitive Relay
  • Priority Charging for Starting Battery
  • Safe for Alternator Outputs up to 120 Amps
  • Fully Automatic, Proven Technology
  • Easy to Install
  • 1 - 140 Amp Voltage Sensitive Relay
  • 19ft - 6ga stranded copper positive battery cable
  • 3ft - 6ga stranded copper ground cable
  • 2 - Positive brass marine type battery terminals
  • 1 - Negative brass marine type battery terminal
  • Crimp lugs & heat shrink
  • Cable ties
  • Easy to follow instructions
How it works:
The dual battery kit allows for safe charging and separation of starting and auxiliary batteries in all 12V marine, auto, RV and solar applications.
When the engine is started, the starting and auxiliary batteries are separated allowing only the starting battery to be charged. When the charge voltage reaches 13.4 volts the voltage sensitive relay engages allowing both the starting and auxiliary batteries to be charged. This is indicated by the light in the top LH corner being illuminated.
When the engine is stopped and the battery voltage falls below 12.9 volts the relay disengages separating the start and auxiliary batteries, at this point the indicator light will be out and the auxiliary battery continues to power any accessories without risk of draining the starting battery.
The smart isolator also has Dual Sensing which senses the charge of both batteries. If either battery is receiving a charge, e.g. a battery charger is connected to the auxiliary battery; the relay will engage and charge both batteries.
The dual battery kit is easy to install and comes with all components and instructions required to complete the install. There is no need to cut into any factory wiring that may void manufacturer's warranty.