Mitsubishi Electric QJ71E71-100 User Manual page 220

Control system (system A)
Tracking cable
*1 When the cable is not connected from the start, the E71 does not determine it as disconnection. (Disconnection is
detected only when normal status turns to abnormal.)
*2 The following shows the timing of issuing the system switching request.
• System switching timing at disconnection detection
Detection for
disconnection is
E71
started after the initial
process is completed.
218
Connected device
Standby system (system B)
The E71 starts disconnection detection after initial process completion. On detection of disconnection, the
E71 performs a disconnection status time check, and when disconnected status continues for the period of
the disconnection detection monitoring time, the E71 issues a system switching request to the control
system CPU module. When the disconnected status returns to normal within the disconnection detection
monitoring time, the E71 does not issue a system switching request.
Disconnected Cable connected
(link down) (link up)
Disconnected
Disconnection detection
monitoring time
3.
After system switching
The system A operates as a standby system, and the
system B as a control system.
Disconnected
(link down)
Disconnected
Disconnection detection
monitoring time
A request for system switching to
the control system CPU is issued.