An industrial automation control system comprising: a power supply subsystem including a first output voltage rail and a second output voltage rail; a functional domain subsystem including processor circuitry (326, 328), volatile memory (332, 330, 530) and non-volatile memory (256a, 256b, 534) configured to monitor and control one or more remote devices operatively associated with the industrial automation control system, wherein the first voltage output rail provides power to the functional domain subsystem during normal mode of operation and wherein the processor circuitry comprises a CPU core and CPU I/O; an energy storage subsystem operatively connected to the second output voltage rail and configured to store energy supplied from the second output voltage rail during the normal mode of operation; a diagnostic domain subsystem configured to perform diagnostics of one or more conditions associated with the functional domain subsystem; a third voltage rail, a fourth voltage rail and a fifth voltage rail powered by the first output voltage rail during normal mode of operation, wherein the third voltage rail is used to power the non-volatile memory, the fourth voltage rail is used to power the CPU core voltage and the fifth voltage rail is used to power the CPU I/O, and wherein the third voltage rail, the fourth voltage rail and the fifth voltage rail are voltage rails deemed as an safety relevant domain; and a voltage monitor (323, 324) operatively associated with monitoring the third voltage rail, the fourth voltage rail and the fifth voltage rail; wherein the diagnostic domain subsystem is powered by the energy storage subsystem using the stored energy during the normal mode of operation, wherein the energy storage subsystem is configured to operatively power the diagnostic subsystem, the third voltage rail, the fourth voltage rail, the fifth voltage rail and the functional domain subsystem during a control system operation associated with a failure of the first output voltage rail due to a fault associated with the first output voltage rail, and wherein the voltage monitor is configured to shut down the first output voltage rail and all of the third, the fourth and the fifth voltage rails in the event of an over-voltage or under-voltage fault in either safety relevant domain voltage rails. a power supply subsystem including a first output voltage rail and a second output voltage rail; a functional domain subsystem including processor circuitry (326, 328), volatile memory (332, 330, 530) and non-volatile memory (256a, 256b, 534) configured to monitor and control one or more remote devices operatively associated with the industrial automation control system, wherein the first voltage output rail provides power to the functional domain subsystem during normal mode of operation and wherein the processor circuitry comprises a CPU core and CPU I/O; an energy storage subsystem operatively connected to the second output voltage rail and configured to store energy supplied from the second output voltage rail during the normal mode of operation; a diagnostic domain subsystem configured to perform diagnostics of one or more conditions associated with the functional domain subsystem; a third voltage rail, a fourth voltage rail and a fifth voltage rail powered by the first output voltage rail during normal mode of operation, wherein the third voltage rail is used to power the non-volatile memory, the fourth voltage rail is used to power the CPU core voltage and the fifth voltage rail is used to power the CPU I/O, and wherein the third voltage rail, the fourth voltage rail and the fifth voltage rail are voltage rails deemed as an safety relevant domain; and a voltage monitor (323, 324) operatively associated with monitoring the third voltage rail, the fourth voltage rail and the fifth voltage rail; wherein the diagnostic domain subsystem is powered by the energy storage subsystem using the stored energy during the normal mode of operation, wherein the energy storage subsystem is configured to operatively power the diagnostic subsystem, the third voltage rail, the fourth voltage rail, the fifth voltage rail and the functional domain subsystem during a control system operation associated with a failure of the first output voltage rail due to a fault associated with the first output voltage rail, and wherein the voltage monitor is configured to shut down the first output voltage rail and all of the third, the fourth and the fifth voltage rails in the event of an over-voltage or under-voltage fault in either safety relevant domain voltage rails.