Mitsubishi Electric MELSEC-QS Series Safety Application Manual page 171

APPENDICES
(2) Calculation example
In the system configuration of Figure APPX.2, when a signal from an emergency stop
switch is input to the CC remote (1), a contactor connected to the CC remote (2) stops
its output. This section describes examples for calculating safety response time for
the situation above, using the following set values.
• WDT setting value for the safety CPU module (1) and (2): 10ms
• Input response time of CC remote (1): 12.2ms
• Output response time of CC remote (2): 10.4ms
• Safety refresh response processing time: 9.6ms
(a) Calculation example of input transmission time of CC-Link Safety
1) Link scan time of CC-Link Safety
This time is required to calculate input transmission time of CC-Link Safety.
The following is the calculation example.
In these example, transmission speed, 10Mbps, is used. (Condition: No
communication error station exists.)
• BT = 0.8
• NI = 1
• NW = 1
• N = 1
• ni = 1
• nw = 1
• A = 0, B = 1
• ST = 950
1) 800 + (0
2) 900 + (1
• TR = 38.4, RT = 0, F = 0
Appendix 2 Calculating Safety Response Time When CC-Link Safety and
CC-Link IE Field Network are Used
8
8
15) = 800
50) = 950
• In synchronous mode
LS = BT (27 + (NI
+ (ni 4.8) + (nw
= 0.8 (27 + (8
+ (1 4.8) + (1
= 180 [ s]
= 0.2 [ms]
• In asynchronous mode
LS = BT (27 + (NI
+ (ni 4.8) + (nw
= 0.8 (27 + (8
+ (1 4.8) + (1
= 1130 [ s]
= 1.2 [ms]
4.8) + (NW 9.6) + (N 30)
9.6) + TR) + RT + F
4.8) + (8 9.6) + (1 30)
9.6) + 38.4) + 0 + 0
4.8) + (NW 9.6) + (N 30)
9.6) + TR) + ST + RT + F
4.8) + (8 9.6) + (1 30)
9.6) + 38.4) + 950 + 0 + 0
1
2
3
4
5
6
APPX
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