Displaying And Modifying Timers/Counters - Siemens SIMATIC S5 TD 390 Manual Del Usuario

Displaying and Modifying Process, Timer, Counter Values and Clock Times
Call up
You can call up this operating mode in two ways:
operating mode
By operating the TD 390 (for operation, see corresponding section).
By setting a flag bit (enable bit) allocated to the corresponding DB
(see Section 8.4).
Activate using
If flag bits are set to call up the DB for displaying messages with counter
flag bits
and timer values or process values, the following rules apply:
The system automatically changes to the function "Display
Timer/Counter" or "Display Process Values".
The flag bit is reset when you confirm the displayed value.
If all flag bits are reset, the system changes to the "Display
Messages" operating mode.
7.2

Displaying and Modifying Timers/Counters

Timer/counter
You can display and set timer and counter values using the "Timers and
values
Counters" function. You can display and modify the initalization values
of timers/counters which are stored in a special DB (see Section 8.4). The
timer/counter value is only changed in the DB and not directly in the
actual timer or counter.
Timers and counters are displayed with the highest priority if the
corresponding flag bits are set; i.e. before process values and messages.
Modify timer/ If you reach the end or start value when you modify the timer or counter
counter values
value, the counting direction continues as follows:
For timers/counters
Process values
7-2
0 to 999 0
–max to +max –max
C79000–K8576–C292–01
TD 390