This is the expansion cabinet to expand the system capacity. Up to three 1632ME EXPs can be connected to the 1632M Main KSU. The KSU shape and structure are exactly same as 1632M KSU, however the capability is different. The following facilities are initially equipped.

• Power supply (110V/240V)
• 1 external the backup battery connector
• 3 mounting spaces for 408E/008E/000E/1PRIU (3rd Slot of each KSU can not use for 4-Wire Multi-Line  Telephone or DSS to the Console.)
• 4 trunks + 8 hybrid Ext I / F
• 1 power failure transfer circuit
• EXIFE-C1 (1 connector for 1632M-A KSU)
• 2 door the unlock relay
• the SLT ringer
• the Message waiting lamp driver

And, the EXIFE DSP provides:

• 32 telephony resources (DTMF / Dial tone / Busy tone / FSK caller-ID receiver / sender)1632ME-A EXP does NOT have CPU and main software, therefore it shall not activate by stand-alone.