
B–63083EN/02
4. POWER SUPPLY CONNECTION
52
Part programs, offset data, and system parameters are stored in CMOS
memory in the control unit. The power to the CMOS memory is backed
up by a lithium battery mounted on the front panel of the control unit. The
above data is not lost even when the main battery goes dead. The backup
battery is mounted on the control unit at shipping. This battery can
maintain the contents of memory for about a year.
When the voltage of the battery becomes low, alarm message “BAT”
blinks on the display and the battery alarm signal is output to the PMC.
When this alarm is displayed, replace the battery as soon as possible. In
general, the battery can be replaced within two or three weeks, however,
this depends on the system configuration.
If the voltage of the battery becomes any lower, memory can no longer
be backed up. Turning on the power to the control unit in this state causes
system alarm 910 (SRAM parity alarm) to occur because the contents of
memory are lost. Clear the entire memory and reenter data after replacing
the battery.
The following two kinds of batteries can be used.
D Lithium battery built into the CNC control unit.
D Two alkaline dry cells (size D) in the external battery case.
NOTE
A lithium battery is installed as standard at the factory.
(1)Prepare a new lithium battery (ordering drawing number:
A02B–0200–K102).
(2)Turn the Series 21i/210i on for about 30 seconds.
(3)Turn the Series 21i/210i off.
(4)Remove the old battery from the top of the CNC control unit.
First unplug the battery connector then take the battery out of its case.
The battery case of a control unit without option slots is located at the
top right end of the unit. That of a control unit with 2 slots is located
in the central area of the top of the unit (between fans).
(5)Insert a new battery and reconnect the connector.
NOTE
Steps (3) to (5) should be completed within the period
indicated below. Do not leave the control unit without a
battery for any longer than the period shown, as this will
result in the contents of memory being lost.
Series 21i: Within 30 minutes
Series 210i with HSSB board: Within 30 minutes
Series 210i with PC functions: Within 5 minutes
4.4
BATTERY
4.4.1
Battery for Memory
Backup (3VDC)
Replacing the lithium
battery