Command: Open And Close Gate - Siemens SIMATIC S7-300 FM 350-1 Manual

7.4.6

Command: Open and close gate

Overview
Gates of FM 350-1:
● A HW gate, level- or edge-triggered.
● A SW gate which you can open and close by setting control bits in the user program.
Selecting a gate
You define which gate you are going to use for the measurement in the mode interface.
The diagrams below illustrate the various options of opening and closing the gates of
FM 350-1.
Level-triggered opening and closing of the HW gate
Figure 7-35
You open the HW gate to start the measurement by setting a signal at digital input DI-Start.
You close the HW gate to stop the measurement by resetting the signal at digital input
DI-Start. The measured value which is valid at the time the HW gate is closed is retained at
the checkback interface.
The level-triggered HW gate is activated by the first positive edge at input DI-Start DI after
you set the parameters.
With this parameter setting, the module does not evaluate input DI-Stop, but indicates its
status at the STS_STP status bit.
FM 350-1 Counter module
Manual, 05/2011, A5E03648639-01
Level-triggered opening and closing of the HW gate (measuring)
Operating Modes, parameters and commands
7.4 Measuring modes
149