Mitsubishi Electric MELIPC MI5000 Series, Руководство пользователя

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7 CC-Link IE Field Network Basic FUNCTION
7.1 Cyclic Transmission
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7
Link scan time after timeout
If a timeout occurs due to the failure of a slave device, the link scan time will be changed depending on the setting value of the
timeout time.
• When the timeout time is shorter than the link scan time, operation follows the configured "Link Scan Time". (
 Page 83
Link scan time settings)
• When the timeout time is longer than the link scan time, operation follows the "Timeout time" configured for "Link scan
settings". (  Page 181 Link scan settings)
To minimize the effect of communication transmission delays with normal slave stations during a timeout,
adjust the timeout time. For example, using CC-Link IE Field Network Basic diagnosis, check the current link
scan time (when all slave stations are operating normally), and then set a timeout time about five times as
long as the link scan time. (When the current link scan time is 10 ms, set 50 ms for the timeout time.)
■ If the master station receives a faulty response from a slave station
The master station immediately disconnects that slave station regardless of the timeout period and disconnection detection
count set in link scan settings. The corresponding slave station generates a data link error. (The error code will be generated
by the slave station.)
The following table shows the operations of special relays and special registers when a slave station is disconnected.
Some slave stations are equipped with a function that makes them disconnected without being an error
station. For details, refer to the manual of the slave station used. (Since the slave station does not become an
error station, 'Data link status' (SM1540) and 'Data link status of each station' (SD1540 to SD1543) do not
change.)
Special relay, special register Operation
'Cyclic transmission status' (SM1536) The device remains ON.
'Cyclic transmission status of each station' (SD1536
to SD1539) The bit corresponding to the station number of the disconnected slave station turns OFF.
'Data link status' (SM1540) OFF to ON
'Data link status of each station' (SD1540 to
SD1543) The bit corresponding to the station number of the disconnected slave station turns ON (indicating that
the slave station is an error station).