Where a public address (PA/GA) system is installed to provide broadcast of potentially life saving emergency speech and alarm tone signals a high integrity configuration is required. This also extends to the AC mains supply energising the PA/GA package. For additional security it is possible to duplicate AC mains supply inputs “PRIMARY“ and “SECONDARY“ thereby ensuring continued PA/GA capability in event of failure of either AC supply input.
The PSC VODEC ASD02 automatically managements the selection of AC mains supply inputs and provides the engineer with details status display on a “front of rack“ LED annunciator panel type ASD08. The ASD02 provides eight independently fuse protected outputs. Which are assigned to VA300+PSU, amplifier power supply units, flashing beacon power supply and auxiliary devices. The ASD sub-system comprises of two parts i.e. ASD02 is a clip on/off DIN rail mounted assembly which facilitates termination mains supply inputs. The ASD08 power management LED annunciator comprises of a low profile 1 unit high 19 inch rack mount panel. With an integral display window it is fitted with secondary fault reporting contacts to enable possible interface to the site DCS/SCADA/Telecom supervisory package. On board high power supply management ensures galvanic isolation between the primary/secondary AC mains supply inputs and facilitates priority selection of online/standby power supply source. The ASD02 carries on board neon indicator sets to facilitate rapid fault finding and service and dedicated high rupture capacity cartridge fuses provide supervised protection for each supply output. Display is extended from the ASD002 via optically isolated outputs which control a rack mount ASD08 LED annunciator display units. A tamper proof test switch is fitted to ASD02 to enable the engineer to manually check the operation of the target PA/GA system on the hot-standby mains supply.