Function description
Operating Manual PSSu K F INC
1001688-EN-09
15
4.2.4
Counter operating mode
"Counter" operating mode is not recommended for safety functions because pulses can be
generated if there are any track errors. Compare errors can arise as a result, which can
lead to a shutdown or to common cause errors.
In "Counter" operating mode, the module's dual-pole, differential inputs A, B, C have the fol-
lowing functions:
}
Input A (Count)
Input A is the input for the encoder's counter pulses. The module counts each rising
edge.
}
Input B (Up/down)
At a 0 signal the module counts forwards. At a 1 signal the module counts backwards.
}
Input C (Gate/Latch)
The counter is stopped with a 1 signal. The module ignores the counter pulses at the in-
put until a 0 signal returns.
C+
G
L
a
b
c
d
e
B+
A+
Legend:
}
a: The counter counts forwards because there is 0 signal at channel B.
}
b: At the next rising edge at channel A, the counter counts backwards because there is
a 1 signal at channel B.
}
c: The counter is disabled because there is a 1 signal at input C.
}
d: The module has received a latch pulse. Provided the function is activated, the
counter value is copied into the latch memory with a rising edge at input L.
}
e: The counter is disabled because there is a 1 signal at input G.