Mitsubishi Electric RD77GF8 User Manual page 64

■Master station (safety station) and remote device station (safety station)
• The safety device status of the Safety CPU on the master station (safety station) is reflected to the safety output of the
remote device station (safety station).
• The safety input status of the remote device station (safety station) is stored in the Safety CPU on the master station (safety
station).
For communications with the remote device station (safety station), 16 points of RWw and 16 points of RWr are used by the
system. Set "RWw/RWr Setting" to 16 points in "Network Configuration Settings" of "Basic Settings". (Page 67 Network
Configuration Settings)
SA\M0
Ò
SA\Y
• Output from the master station (safety station)
 The safety device of the Safety CPU on the master station (safety station) turns on.
 The safety device status of the Safety CPU on the master station (safety station) is stored in the Safety CPU on the remote device station (safety station) by
safety data transfer.
 The safety output status of the remote device station (safety station) is output to an external device.
• Input form the remote device station (safety station)
 The status of the external device is stored in the safety input of the remote device station (safety station).
 The safety device status of the Safety CPU on the remote device station (safety station) is stored in the Safety CPU on the master station (safety station) by
safety data transfer.
Do not write any data to the area (RWw and RWr) used by the system.
Doing so may cause malfunction of the programmable controller system.
■Setting method
Set safety communications in "Safety Communication Setting" under "Application Settings". (Page 81 Safety
Communication Setting)
How to count the number of safety connections
The maximum number of safety connections per network is 1814. If exceeding this limit, safety communications are not
guaranteed. The number of safety connections can be calculated using the following formulas:
Number of safety connections = M + (L  2)
M: Number of all the safety connections set in the master station (safety station)
L: Number of all the safety connections set in the local station (safety station) that perform safety communications with local stations (safety stations)
1 FUNCTIONS
62
1.6 Safety Communication Function
Station No.0
Safety CPU
Master station
(safety station)
Safety device
Sequence
scan
Remote device station (safety station)
Station No.1
Main module
Ó
Safety input
Ö
Extension
module
Safety output
Ô
External device
Õ
External device