Using Battery Backup
An optional lithium battery is available to maintain the system RAM retentive memory when
the DL205 system is without external power. Typical CPU battery life is five years, which
includes PLC runtime and normal shutdown periods. However, consider installing a fresh
battery if your battery has not been changed recently and the system will be shut down for a
period of more than ten days.
NOTE:
Before installing or replacing your CPU battery, back-up your V-memory and system parameters.
You can do this by using
Direct
SOFT to save the program, V-memory, and system parameters to
hard/floppy disk on a personal computer.
To install the D2–BAT CPU battery in DL230 or
DL240 CPUs:
1. Gently push the battery connector onto the circuit
board connector.
2. Push the battery into the retaining clip. Don’t use
excessive force. You may break the retaining clip.
3. Make a note of the date the battery was installed.
To install the D2–BAT–1 CPU battery in the DL250–1/DL260
CPUs: (#CR2354)
1. Press the retaining clip on the battery door down and swing the
battery door open.
2. Place the battery into the coin–type slot with the +, or larger, side
out.
3. Close the battery door making sure that it locks securely in place.
4. Make a note of the date the battery was installed.
WARNING: Do not attempt to recharge the battery or dispose of an old battery by fire. The battery may
explode or release hazardous materials.
Battery Backup
The battery backup is available immediately after the battery has been installed in the DL205
CPUs.
The battery low (BATT) indicator will turn on if the battery is less than 2.5VDC
(refer to the Status Indicator table on page 3-12). Special Relay 43 (SP43) will also be
activated. The low battery indication is enabled by setting bit 12 of V7633 (B7633.12). If the
low battery feature is not desired, do not set bit V7633.12.
The super capacitor will retain memory IF it is configured as retentive regardless of the state
of B7633.12. The battery will be the same, but for a much longer time.
DL205 User Manual, 4th Edition, Rev. B
3–14
Chapter 3: CPU Specifications and Operations
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
DL230 and DL240
-1
DL250-1 and DL260
DL230 and DL240