The REDARC Smart Start SBI24 is a dual battery isolator used to isolate the start and auxiliary batteries in a dual battery system. The microprocessor-controlled smart battery isolator protects the primary battery from a low charge in the secondary battery so it won't drain the primary battery, at the same time allowing the auxiliary battery to supply non-essential loads. The SBI24 provides 24V DC incorporating 100A of continuous ratings. Used mainly in commercial vehicle dual battery systems, the Smart Start SBI24 battery isolator incorporates components that prevent the solenoid from generating high voltage transients. It's used in place of a diode battery isolator due to the voltage drop associated with diode type isolation. The sophisticated fault detection and LED indication of operation alerts users of over-voltage or voltage drops. It is compact, easy to install, and provides full surge protection. The Smart Start SBI24 Battery Isolator is a safe way to charge a dual battery system.. . . . .