8030-PS-11. The Symax Class 8030 Type PS11 power supply provides low-voltage DC power for the components of Symax programmable controller systems. All Symax power supplies have incoming power terminals, connectors for I/O rack modules, and a front-accessible fuses or circuit breaker. Each Symax power supply also contains three \"D\" cell alkaline batteries that provide backup power to racks in the event of line power failure. This backup retains programs and register data stored in random access memory that is contained in various Symax devices.