Items Checked When Multiplexed Remote I/O Network For Redundant System Does Not Operate Normally; Items Checked When A Minor Error (Continue Error) On A Remote I/O Station Cannot Be Detected - Mitsubishi Electric MELSEC Q Series Reference Manual

8 TROUBLESHOOTING
8.2.8 Items checked when multiplexed remote I/O network for redundant system does not
operate normally
Check item
Isn't the power supply module of the standby
system turned off?
Hasn't a stop error occurred in the standby system
CPU?
Hasn't an error occurred in the master module
mounted on the main base unit of the standby
system?
Check item
Hasn't an error occurred on a remote I/O station
with function version C or earlier?
Check item
Is the send range of the host a tracking range?
8.2.9 Items checked when a minor error (continue error) on a remote I/O station cannot be
detected
Check item
Has SB000F of the remote master station turned
ON?
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(1) Redundant CPU does not perform system switching even when the
data link cable is disconnected.
Confirm the status of the external power supply of the standby system.
Connect GX Developer to the standby system CPU and execute PLC diagnostics to
check if any error has occurred.
Confirm the operation status of the master module of the standby system.
(2) Errors on a remote I/O station cannot be detected by the
programmable controller CPU of the master operation station.
Check the product information of the remote I/O module of the remote I/O station by the
system monitor of GX Developer.
(3) Cyclic data are turned off continuously or instantaneously when
system switching is performed on Redundant CPU.
Confirm if the devices in the send range of the host is set as tracking devices with the
parameters of GX Developer.
Turn OFF SB000F of the remote master station.
Checking procedure
Checking procedure
Checking procedure
Check procedure
MELSEC-Q
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