Hardware reference guide

Intelligent/Special Purpose
416
35013379 02 October 2007
A/B Designation
Slide Switch
The slide switch is used to designate the controller as A or B. The slide switch on
one Hot Standby module in every pair must be set to A; the switch on the other must
be set to B. The controller designated A will begin as the primary controller as long
as it reaches the ready state before or at the same time as controller B. If the
switches are set to the same position, the system will refuse to recognize the second
controller at startup.The following figure shows the A/B designation slide switch.
A
B
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