The REDARC Smart Start SBI24D is a dual battery isolator that is easy to install and is used to isolate start and auxiliary batteries in a dual battery system. It protects the start battery from a low charge in the secondary battery so it won't drain the primary battery. The SBI24D provides 24 volt DC incorporating 100A of continuous ratings. The dual sensing model isolates the start and auxiliary batteries in a system where the auxiliary battery may also be charged by solar panels or another external source. It also allows the start battery to be charged from the external source once the auxiliary battery reaches 26.4 volts. Power saving technology includes components which prevent the solenoid from generating high voltage transients. Sophisticated fault detection and LED indication of operation alerts the user of over-voltage, voltage drop, and excessive current draw conditions. The Smart Start SBI24D is surge protected and a safe way to charge auxiliary batteries. It's primarily used in commercial vehicles. The SBI range manages battery charge for your secondary battery banks while on the move.