Mitsubishi Electric melsec q00ujcpu User Manual page 543

(17) For redundant systems (Trucking)
SD1700 to SD1779 is valid only for redundant systems.
These are all 0 for stand-alone systems.
Number Name Meaning
Tracking error Tracking error
SD1700
detection count detection count
Waiting time for
Waiting time for
online program
online program
SD1710 change
change (standby
(standby
system)
system)
12 - 77
Table12.36 Special register
Explanation
• When the tracking error is detected, count is added by one.
• The counter repeats an increment and decrement of the value; 0
32767 - 32768 0
• Set in seconds the waiting time of the standby system CPU module from
when online program change to the control system CPU module is
completed by the online program change for redundancy function until
the online program change to the standby system CPU module starts.
• If no online program change request is issued to the standby system
CPU module within the preset time after completion of the online
program change to the control system CPU module, both system CPU
modules judge it as the failure of the online program change for
redundancy. In this case, both system CPU modules resume the
consistency check between system A & B suspended during the online
program change. Also, the control system CPU module is set to accept a
new request of online program change for redundancy.
• When both systems are powered on, 90 seconds are set to SD1710 as
the default value.
• Set the value within the range 90 to 3600 seconds. When the setting is 0
to 89 seconds, it is regarded as 90 seconds for operation. If the setting is
outside the allowed range, it is regarded other than 0 to 3600 seconds
for operation.
• The waiting time for a start of online program change to the standby
system CPU module is checked according to the SD1710 setting during
online change of multiple blocks and online change of batch of files for
redundancy.
Corres-
Set by ponding Corresponding
ACPU
(When Set)
D9
S(Error)
New
U/ S (Initial)
CPU
QnPRH
QnPRH