APC Symmetra Power Module
The power processing system in SymmetraTM is comprised of an individual power module(s). Each power module contains the electronics for a complete 4kVA UPS, including the rectifier, charger, and inverter. When two or more power modules are present, they operate in parallel, sharing the load equally. By configuring the system with at least one more power module than is required to power the load (a redundant power module), SymmetraTM can sustain a power module failure, and still deliver full power to the load equipment. The failed module is identified by the control/user interface system, an alarm is initiated to notify the user of the module failure, and the hot-swappable module can be replaced by the user, without the need to power down the load equipment. A SymmetraTM MiniFrame provides bays for up to three power modules, and a MasterFrame provides bays for up to five. This provides the full system capacity (8kVA and 16kVA respectively), plus one redundant power module.