The Digital Voltage Sensing Relay (DVSR) allows the charging of a second battery bank from any single charging source. When the voltage on the charged bank rises sufficiently, the DVSR engages allowing the 2nd battery bank to charge. When charging stops and voltage falls, the DVSR automatically isolates the battery banks, ensuring that engine start batteries are kept fully charged. Digital circuitry provides superior reliability and extremely low power consumption. Digital enhancements have introduced remote sensing circuitry that allows an optional connection from the ignition switch to provide the same functionality as single sense VSR and zero power consumption when engine is off. Another benefit is a zero stand by current draw when remote sensing circuit is utilized with a storage mode switch fitted (switch in open position).