Appendix e – Rockwell Automation 57C423 Common Memory Module User Manual
Page 35
EĆ1
Appendix E
How Removing/Replacing The Common
Memory Module Affects Tasks and
Variables in a DCS 5000 Rack
The following tables illustrate how removing or replacing the Common Memory
module affects tasks and variables in a DCS 5000 rack. (Refer to Appendix F for
information regarding the effect on tasks and variables in an AutoMax rack.)In
each case, assume a BASIC task has written to variables in both the Processor
(local)and the Common Memory module (common). Also assume the task was
stopped before power was removed from the rack.
The following information applies only if an external battery backup (57C492)is
connected to the power supply. The external battery backup is required for DCS
5000 Processor memory backup. If the battery backup is not used, all tasks are
deleted when power is removed from the rack.
Common Memory Module Located In Slot 0
For the following, assume the Common Memory module is in slot 0 and a
Processor module is in slot 1.
Status of Data
Common
Action
App.
Task
Deleted?
App.
Task
Status
NonVol
Vol
Local
Replace 57C413A with
Same or new 57C413A
ąAt power up
YES*
N/A
N/A
N/A
N/A
Replace 57C413A with
New 57C413B or 57C423
ąAt power up
NO
UNINSTALLED*
N/A
N/A
N/A
Replace 57C413B or
57C423 with new or used
57C413B or 57C423
(module may contain data
from another application)
ąAt power up
Error Code 13 appears on Processor LEDs**
Replace battery on
57C413B or 57C423 and
return same module to
rack
ąAt power up***
NO
STOP
Data OK
Zero
Data OK
*
You must reĆload the configuration and application tasks onto the rack. This
procedure is described in the Programming Executive instruction manual
(JĆ3630).
** Select DOWNLOAD from the ON LINE menu to download the configuration
and application tasks. Select ERROR CLEAR to clear the LED fault code on
the Processor module. Refer to JĆ3630 for more information about the ON
LINE menu.
*** Assumes superĆcapacitor has maintained memory on the module during the
time required to replace the battery.