Rockwell Automation 8520 9/Series CNC Integration Maintenance Manual Documentation Set - Manual (Page 771)

Section 15B
Replacement Procedures
15B-15
You may be required in the case of hardware failure to replace the 9/230
Processor Board. When you remove the processor board from the
enclosure, you also must remove the software option chip and the flash
memory SIMMs. The software option chip turns on all the optional
features that you purchased with the control. To replace the processor
board:
1. Turn OFF all power to the control.
ATTENTION: To guard against electrical shock hazards, never
make connections or disconnections at the ac distribution
network unless the main ac disconnect switch is open and
locked.
2. Remove all connections to the motherboard, including:
battery
I/O ring
E-stop wiring
Video
RS-232/422 communications
touch probe
auxiliary analog out
all axis cables
Remote I/O
15B.5
Replacing the Processor
Board on the 9/230 Analog