Mitsubishi MELSEC Q Series Programming Manual page 1189

(14) Redundant system (tracking information)
The special relay (SM1700 to SM1799) is valid when the redundant system is in backup mode or in separate
mode. All bits are set to off for stand-alone systems.
Number
Name
OFF : Transfer not
Transfer trigger
SM1700
completion flag ON : Transfer
ON : Manual system
Manual system
switching disable/
enable setting
SM1709 during online
program change
OFF : Manual system
redundant
tracking
Transfer tracking OFF : No device
data during online
SM1710
program change ON : Transfer device
enable flag
Meaning
This relay remains on for one scan upon
completed
completion of a transfer for any of the blocks 1 to
64.
completed
• This relay is turned from off to on to enable the
user to switch a system during online program
change for redundancy.
After the manual system switching disable
status is canceled, the system automatically
turns off SM1709.
• A system can be switched even a online
program change for redundancy is being
switching performed and regardless of the status of this
enabled relay, if the reason for the switching is any of the
(Disable following:
canceled) •Power-off
•Reset
switching •Hardware failure
disabled •CPU stop error
• The system switching disable status can also be
canceled by this relay during the following
states.
•Multiple-block online program change
redundant tracking execution status
•File batch online program change redundant
tracking execution status
• This relay specifies whether to execute a
tracking transfer for the following control data
during online program change for redundancy.
•Device memory (Including SMs and SDs that
automatically execute a tracking transfer)
•PIDINIT information, S.PIDINIT information,
tracking SFC information
• SM1710 can be also used to specify whether to
memory enable a tracking transfer whhle multiple-block
online program change redundant tracking and
while file batch online program change
redundant tracking.
• SM1710 is transferred from the cjntrol system to
the standby system by tracking transfer.
Explanation
S (Request)/U
Corres-
Corres-
Set by ponding
ponding
(When Set) ACPU
CPU
M9
S (Status
change)
New QnPRH
U
App-181
8
8
8
8
A
6
7
8