Ctu - ABB ACSM1 Firmware Manual

Operation
Inputs
Outputs

CTU

(10049)
Illustration
Execution time
The counter output (CV) value is decreased by 1 if the counter input (CD) value
changes from 0 -> 1 and the load input (LD) value is 0. If the load input (LD) value is 1,
the preset input (PV) value is stored as the counter output (CV) value. If the counter
output has reached its minimum value -2147483648, the counter output remains
unchanged.
The status output (Q) is 1 if the counter output (CV) value < 0.
Example:
LD CD
0 1 -> 0
0 0 -> 1
1 1 -> 0
1 0 -> 1
0 0 -> 1
1 1 -> 0
0 0 -> 1
CV is the previous cycle counter output value.
prev
Counter input (CD): Boolean
Load input (LD): Boolean
Preset input (PV): DINT
Status output (Q): Boolean
Counter output (CV): DINT
TLA1 1 msec
>CU
R
PV
0.92 µs
PV Q
10 0
10 0
-2 1
1 0
5 1
-2147483648 1
10 1
CTU
95
(1)
CV(95)
CV
Q(95)
Q
CV CV
prev
5 5
5 5 - 1 = 4
4 -2
-2 1
1 1 -1 = 0
0 -2147483648
-2147483648 -2147483648
Standard function blocks
251