Duplex Processing Cycle Time Extension (Duplex Cpu Systems Only) - Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual

Computing the Cycle Time
9-4-7 Duplex Processing Cycle Time Extension (Duplex CPU Systems
Only)
Cycle Time Extension for
Duplex Initialization
Cycle Time Extension
when Switching to
Standby CPU Unit
Error switching Cycle time
operation extension
Switch with CPU 11.5 ms
Unit switch setting
CPU error (WDT 125.5 ms
error)
The cycle time for a Duplex CPU System can be extended at various times as
described below. Enter actual system operation only after verifying that the
system operates correctly for the maximum possible cycle time.
The cycle time will be increased over the normal cycle time whenever duplex
operation is initialized, including when power is turned ON, when the initializa-
tion button is pressed, when operation is started, and when data is trans-
ferred. The maximum increases are listed in the following table. The maximum
cycle time would thus be the normal cycle time plus the increase in the cycle
time for duplex initialization shown in the following table.
CPU Unit model
CS1D-CPU65H 190 ms +A
CS1D-CPU67H 520 ms +A
A is the time added when duplex Inner Boards are mounted. Refer to the
Inner Board Operation Manual for the value of A.
Example: The maximum cycle times would be as shown in the following table
if the normal cycle time was 20 ms.
CPU Unit model
CS1D-CPU65H 20 ms + 190 ms = 210 ms
CS1D-CPU67H 20 ms + 520 ms = 540 ms
Set the monitoring time (10 to 40,000 ms, default: 1 s) +B* for the cycle time
high enough to allow for this increase. Also, confirm that the system will oper-
ate correctly and safely even for the maximum cycle time, including the
increase for duplex initialization.
*B is the time added to the cycle-time monitoring time only for duplex initializa-
tion when duplex Inner Boards are mounted. Refer to the Inner Board Opera-
tion Manual for the value of B.
The cycle time will be extended if an error occurs in the active CPU Unit that
causes operation to be switched to the standby CPU Unit.
Error switching
operation
There are two factors involved in the cycle time extension:
• Time required to detect the error causing operation to switch
• Time required to actually switch operation to the standby CPU Unit.
The following table list the time by which the cycle time will be extended
depending on the error that caused operation to be switched.
Time required to detect switch setting: 11 ms
Operation switching time: 0.5 ms
Time required to detect microcomputer WDT error in the CS1D: 125 ms
Operation switching time: 0.5 ms
Increase in cycle time
Maximum cycle time
Processing to
switch operation
Remarks
Section 9-4
355