This section is only used for application simulation. It should therefore not be used if a PLC is connected.
Illustration of the Simulation Section
The section below is part of the MAST task. It has no condition defined for it so it is permanently executed:
NOTE: For more information on creating an LD section, refer to chapter
LD Editor.
Description of the Simulation Section
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The first line of the illustration is used to simulate the value of the Lim_valve_opening variable. If the valve opening command is given (Valve_opening_cmd = 1), a TON timer is triggered. When the PT time is reached, the TON output switches to "1" and increments the Lim_valve_opening output to "1" unless the valve closure command is given at the same time.
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Same principle applies to the Lim_valve_closure and Contactor_return outputs.
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The last part of the section is used for the simulation of the tank level and for triggering the different tank levels. The OPERATE and COMPARE blocks from the library can be used to do this.