The REDARC Smart Start SBI12 is a microprocessor-controlled battery isolator which protects the start battery from excessive discharge, while allowing the auxiliary battery to supply charge to non-essential loads. It is used as a solenoid priority system in dual battery systems and provides 12V DC incorporating 100A of continuous ratings. The SBI range manages battery charge for your secondary battery while on the move. The battery isolator is mostly used in 4WD and commercial vehicles. It incorporates electronic components that prevents the solenoid from generating high voltage transients. Due to the voltage drop associated with diode type isolation, it's better than a diode battery isolator. A low standby current draw and fault detection and LED indication of operation warns users of faults such as voltage drops, over-voltage, and excessive current draw conditions. Safely maintain the charge your dual battery system with the Smart Start SBI12 battery isolator.