6
REDUNDANT SYSTEM NETWORKS
6.1 Communication with GX Developer and PX Developer
6.1.3 Cautions on Access from GX Developer and PX Developer
6
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SYS
TEM
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DUNDA
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FUNCTIONS
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RE
DUN
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PR
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TR
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U
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S
HOOTING
[Example]
If a line down occurs in system A during access when PX Developer (monitoring
tools) is connected to that system, and the connection target is specified as
system A, communication is continued with system A via system B.
POINT
Communication via a tracking cable is carried out when the route system's power
supply is on, and the tracking cable is connected properly.
Communication via a tracking cable is not carried out in the following cases.
• When the route system's power supply is off
• When the route CPU module is reset
• When a watchdog timer error occurs in the route CPU module
• When the connected system's power supply is off
• When the connected CPU module is reset
• When a watchdog timer error occurs in the connected CPU module
• When the tracking cable is not connected or broken.
Diagram 6.5 Communication continuation through system switching
System A -
Control System
System B -
Standby System
GX Developer
Ethernet
The line is down
Tracking cable
Ethernet
System switching
System A -
Control System
System B -
Standby System
Tracking cable
GX Developer
When the line is down,
communication continues
via an alternate path.