Timer Variable ($Ac_Timer[N]) - Siemens SINUMERIK 828D Programming Manual

Motion synchronous actions
10.3 Main run variables for synchronized actions
10.3.9

Timer variable ($AC_Timer[n])

Function
System variable $AC_TIMER[n] permits actions to be started after defined periods of delay.
Timer variable: Data type:REAL
$AC_TIMER[n]
s
n
Setting timers
Incrementation of a timer variable is started by means of value assignment:
$AC_TIMER[n]=value
n :
value:
Stopping timers
Incrementation of a timer variable can be stopped by assigning a negative value:
$AC_TIMER[n]=-1
Reading timers
The current timer value can be read whether the timer variable is running or has been
stopped. After a timer variable has been stopped through the assignment of -1, the current
time value remains stored and can be read.
Example
Output of an actual value via analog output 500 ms after detection of a digital input:
Program code
WHEN $A_IN[1] == 1 DO $AC_TIMER[1]=0
WHEN $AC_TIMER[1]>=0.5 DO $A_OUTA[3]=$AA_IM[X] $AC_TIMER[1]=-1
568
Channel-specific timer of data type REAL
Unit in seconds
Index of timer variable
Number of time variables
Starting value (generally "0")
Comments
; Reset and start timer
Programming Manual, 07/2010, 6FC5398-2BP40-0BA0
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