Mitsubishi Electric Melsec-QS Series Safety Application Manual page 80

APPENDIX
Safety
master
station
App
Appendix.1 Calculation Method of Safety Response Time
- 7
(3) Calculation example of link scan time
(2) The following shows the calculation example of LS (Link scan time) used in the
calculation of response time.
The following shows the calculation example when the transmission speed is 10
Mbps in the following system configuration example (It is assumed that there is no
faulty stations).
*1
Station No.1 Station No.2
Safety remote Standard remote
I/O station I/O station
*1: 1 occupied station *2: 2 occupied station
BT = 0.8
NI = 5 8
NW = 5
N = 4
ni = 5
nw = 4
A = 2, B = 5
ST = 1350
1) 800 + (2
2) 900 + (5
1) In synchronous mode
LS = BT
+ TR) + RT + F
= 0.8
+ 0 + 0
= 290.4 [ s]
= 0.4 [ms]
2) In asynchronous mode
LS = BT
+ TR) + ST + RT + F
= 0.8
+ 38.4) + 1150 + 0 + 0
= 1440.4 [ s]
= 1.4 [ms]
*1 *2
Station No.3
Remote device
station
8
15) = 830
50) = 1150
(27 + (NI 4.8) + (NW
(27 + (8 4.8) + (8
(27 + (NI 4.8) + (NW
(27 + (8 4.8) + (8
*1
Station No.5 Station No.6
Safety remote Reserved
I/O station
9.6) + (N 30) + (ni
9.6) + (4 30) + (5 4.8) + (4
9.6) + (N 30) + (ni
9.6) + (4 30) + (5 4.8) + (4
*2
station
4.8) + (nw 9.6)
9.6) + 38.4)
4.8) + (nw 9.6)
9.6)