SMAR LC700 - Page 57

Modules And Accessories
3.19
Turn Rio breaker on
Turn CPU1 and CPU2
breakers on
Start counter
CPU2 found CPU1?
Yes
CPU1was active in
last power down?
Yes
CPU2 was passive in last
power down?
Is CPU1 the main
CPU?
Yes
Is CPU2 the Back
up CPU?
CPU1 gets active
Yes
Yes
Signalize error
No
No
Is CPU2 the Back up
CPU?
Yes
No
CPU2 gets active
CPU2 was passive in last
power down?
No
No
CPU2 gets active
NoYes
No
Counter>=2sec
No
Check conditions
Yes
CPU1 and CPU2 become
passive
Figure 3.9 - Flow chart representing the algorithm that decides which CPU will be active