KEY SERVICE UNIT The Key Service Unit (KSU) for the Electra Elite IPK System provides up to 144 ports and can be expanded to a maximum of 192 ports with addition of 2 expansion KSUs: (Same unit used as expansion KSU) The P64-U10 PSU (power supply unit), backup batteries, two RCA jacks for external paging and MOH input, three DB9 serial interface are included with each KSU. |