Hardware manual

28
Backup by Backup Battery
Table 2.4
Backup item Backup periods Remarks
RAM and RTC 0 to 10 minutes The backup for RAM and RTC (integrated clock) is about 10
minutes by integrated timer. After elapse of 10 minutes, the backup
is for only the RTC.
RTC 10 minutes to 4
days
The over-discharge protection starts when remaining capacity of
the memory backup battery is at 10 percent.
Once the over-discharge protection takes place, the backup to the
RTC stops.
Cyclic Life of Memory Backup Battery
The more the memory backup battery is used often, the more quickly deterioration on the cyclic life worsens.
See the table below. Note that the life period in the above explanation is based on condition that memory
backup for 10 minutes or RTC backup for 3 days is no longer possible.
Table 2.5
Content backed up and period
Used capacity of
memory backup battery
No. of cyclic life of
charge/discharge
Memory +RTC for 10minutes 1% or less About 20,000 times
RTC for 1 day About 5% About 3,000 times
RTC for 2 days About 9% About 1,000 times
RTC for 4 days About 18% About 500 times
RTC for 6 days About 27% About 275 times
RTC for 8 days About 36% About 160 times
RTC for 10 days About 45% About 110 times
RTC for 12 days About 54% About 90 times
RTC for 14 days About 63% About 75 times
RTC for 16 days About 72% About 60 times
RTC for 18 days About 81% About 55 times
RTC for 20 days About 90% About 50 times
Therefore, excluding the cases below, always install battery pack fully charged in the terminal so that the
contents can be backed up by the battery pack (see note) instead by the memory backup battery.
• Long-term storage exceeding over 1.5 months period.
• Backup for the RTC within one day period, relatively the rate of use with the terminal is less.
Note:
The contents in the table can be backed up for approximately 30 days by battery pack (HA-G20BAT ) fully
charged.