a system and method for providing power to a set of logic cards that enables approximately twice as much power to be supplied to the logic cards than would normally be available using conventional power supply systems and methods . the system includes a system backplane having a split power plane , wherein each half of the split power plane receives power from a separate power supply circuit . preferably , the power supply circuits comprise circuit portions of a power entry module , which typically is connected to a pair of service points provided by a dc or an ac power source . the pem and system backplane include circuitry to enable a single backplane to be powered by two separate power supplies , thereby providing the system backplane and the set of logic cards with approximately twice as much power than could normally be provided by a single service point . to facilitate this capability , the pem includes circuitry for detecting the power supplied by each of its power supply circuits and for automatically shutting down power supply to the system backplane in the event of a detected failure condition , such as an undervoltage condition on one or both of the power supplies , and a voltage differential between the power supplies that exceeds a predetermined threshold . the system and method also provides for the use of a second pem that is used in situations requiring a redundant power supply system .