Clock/Calendar

The battery on the CPU retains the Clock/Calendar when the CPU encounters a power loss. With a fully charged battery, the settings are retained for approximately three years.
The system programmed memory (Customer Database) is stored in Nonvolatile Memory and can be erased only by performing a First Initialization.
For additional storage time and the database can be copied to the Compact Flash card on the CPU.
Conditions
• The battery on the CPU should be removed during long term storage but must be installed (protection against loss of power) just before ETU installation to provide battery backup for System Memory.
• When fully charged, the battery retains System Memory for approximately three years.
• You should replace the CPU battery every three years.
• During normal operation, the battery is continually recharged using a built-in charging circuit from the CPU.
• Battery backup on the CPU does not protect the following:
- Callback
- Off-line Status (for programming system or station assignments)
- Repeat Redial
- Trunk Queuing/Camp-On