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Digital modules
8.4 SM 326; DI 8 x NAMUR
Fail-safe signal modules
126
Installation and Operating Manual, 01/2010, A5E00085586-10
Technical data
Sensor selection data
Sensor
In accordance with DIN 19234 or NAMUR
Input current
For "0" signal
0.35 to 1.2 mA
For "1" signal
2.1 to 7 mA
Time, Frequency
Internal signal preparation time (without input
delay) for
Typ.
Max.
Standard mode
55 ms
60 ms
Safety mode
55 ms
60 ms
Input delay
For "0" after "1"
1.2 ms to 3 ms
For "1" after "0"
1.2 ms to 3 ms
Acknowledgment time
In safety mode
Max. 68 ms
Minimum sensor signal duration
Min. 38 ms
Note
The maximum cable lengths currently specified in this manual ensure against functional
impairment, even without more precise examination of the boundary conditions. If the
boundary conditions, such as EMC, cable type, cable routing, etc. are examined more
closely, longer cables can be used for all F-SMs.