Siemens simatic s7-400 FM 450-1, User Manual, Page: 79 / 130

Modes, settings, parameters and commands
8.12 Initiating a process interrupt
Counter module FM 450-1
Manual, 02/2014, A5E03648739-02
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8.9 Setting: Pulse duration
Introduction
As a means of adaptation to the actors used in your process (contactors, control elements
etc.) you have the possibility of specifying a pulse duration during which the outputs are set
when a comparison value is reached. This section describes what you must take into
account if you want to define a pulse duration for the outputs.
The effect of the pulse duration setting
Via the pulse duration you also specify for how long the output should be set at minimum.
This setting is only effective if you preselect the behavior of the output accordingly. The
pulse duration is without effect if the output is to be set between the comparison value and
overflow or underflow.
Pulse duration begins when the output is set. Inaccuracy of the pulse duration is less than
1°ms.
Value range
You can prescribe a value between 0 and 500°ms for the pulse duration. This value applies
to both outputs together.
Note
If you specify the pulse duration to be zero you must ensure that the count pulse times are
greater than the minimum operation time of the digital outputs (operating time:°300°µs, i°e.
the count frequency is less than 3333°Hz); otherwise the control pulses are lost at the
outputs.
In this case check if your actor can respond with the operating time 300°µs.
Default value
The default value for the pulse duration is 0.