Siemens SINUMERIK 808D ADVANCED Training Manual page 84

PLC program
design and
adjustment
Operation symbols of PLC programming language
Counter
Counter: C
Form;
condition of counter bit C3, C25; - represents the
comparison result of the counter and present value.
Style:
plus counter CTU count: counter value+1；
R=1 counter resets; counter value>preset value
Cn=1
minus counter CTD count: counter value -1；
LD counter value = preset; value = counter value=0
Cn=1
plus and minus counter CTUD plus counter:
counter value+1；
minus counter: counter value R=1 counter
resets: counter value>preset value C=1
Commissioning Guide
Plus
counter
CTU
CU
R
PV
PV: is preset
value
Page 84
s
Minus
counter
CTD
CD
LD
PV
CD: is minus
CU: is plus count
count pulse
pulse
LD: is Loading R:
preset value Is resetting
808D ADVANCED Turning and Milling
Plus and
minus
counter
CTUD
CU
CD
R
PV