Mitsubishi Electric RD77GF8 User Manual page 177

Transmission interval monitoring time
The value of transmission interval monitoring time set in the Simple Motion module must satisfy all of the following conditions.
Communication destination
Master station (safety station) or local station
(safety station)
Remote device station (safety station)
TM: Transmission interval monitoring time
SCown: Safety cycle time of the own station (MELSEC iQ-R CPU Module User's Manual (Application))
SCoth: Safety cycle time of the communication destination (MELSEC iQ-R CPU Module User's Manual (Application))
LS: Link scan time (Page 169 Link scan time)
SRref: Safety remote station refresh response processing time of the communication destination (Manual for the remote
device station used)
• Calculate the link scan time used for calculation of the transmission interval monitoring time in accordance
with the conditions of the system used. If disconnection and return of stations are not considered in a
system using the Safety CPU, transmission interval monitoring time can be shortened by setting Kd
(maximum data link processing time when the station is disconnected from or returned to the network) to 0.
However, the Safety CPU may detect a safety communication timeout if the station is disconnected or
returned. If the Safety CPU detects a safety communication timeout, change the transmission interval
monitoring time to a greater value.
• If the Safety CPU detects a safety communication timeout, check that the transmission interval monitoring
time satisfies the above formula.
• When the transmission interval monitoring time has changed, the safety refresh monitoring time must also
be changed to meet the conditions specified for the safety refresh monitoring time. (Page 176 Safety
refresh monitoring time)
Condition
• TM  SCown  3
• TM  SCoth  2 + LS  2
• TM  SCown  3
• TM  SRref  2 +LS  2
APPX
Appendix 6 Processing Time
A
175