Siemens SIMATIC S7-1200 Manual page 105

Table 6- 13 Preset timer -(PT)- and Reset timer -(RT)- coil instructions
LAD Description
Use the Preset timer -(PT)- and Reset timer -(RT)- coil instructions with either box or coil timers. These
coil instructions can be placed in a mid-line position. The coil output power flow status is always the same
as the coil input status.
When the -(PT)- coil is activated, the PRESET time element of the specified IEC_Timer DB data is

reset to 0.
When the -(RT)- coil is activated, the ELAPSED time element of the specified IEC_Timer DB data is

reset to 0.
Table 6- 14 Data types for the parameters
Parameter
Box: IN
Coil: Power flow
R
Box: PT
Coil: "PRESET_Tag"
Box: Q
Coil: DBdata.Q
Box: ET
Coil: DBdata.ET
Table 6- 15 Effect of value changes in the PT and IN parameters
Timer Changes in the PT and IN box parameters and the corresponding coil parameters
TP
Changing PT has no effect while the timer runs.

Changing IN has no effect while the timer runs.

TON
Changing PT has no effect while the timer runs.

Changing IN to FALSE, while the timer runs, resets and stops the timer.

TOF
Changing PT has no effect while the timer runs.

Changing IN to TRUE, while the timer runs, resets and stops the timer.

TONR
Changing PT has no effect while the timer runs, but has an effect when the timer resumes.

Changing IN to FALSE, while the timer runs, stops the timer but does not reset the timer. Changing IN

back to TRUE will cause the timer to start timing from the accumulated time value.
Easy Book
Manual, 11/2011, A5E02486774-04
Data type Description
Bool TP, TON, and TONR:
Box: 0=Disable timer, 1=Enable timer
Coil: No power flow=Disable timer, Power flow=Enable timer
TOF:
Box: 0=Enable timer, 1=Disable timer
Coil: No power flow=Enable timer, Power flow=Disable timer
Bool TONR box only:
0=No reset
1= Reset elapsed time and Q bit to 0
Time Timer box or coil: Preset time input
Bool Timer box: Q box output or Q bit in the timer DB data
Timer coil: you can only address the Q bit in the timer DB data
Time Timer box: ET (elapsed time) box output or ET time value in the timer DB
data
Timer coil: you can only address the ET time value in the timer DB data.
6.3 Powerful instructions make programming easy
Programming made easy
105