Micromod MOD: 30ML Display Script Guide - Manual (Page 82)

MOD 30ML Display Guide
Application Examples
5.7 Example 7: Start & Stop a Discrete Device
Motors, pumps, solenoid valves and other discrete devices can be commanded from the
MOD 30ML display, taking the place of separate display terminals or pushbuttons. This
example illustrates stop and start of a motor. The Start/Stop commands and the feedback
can be shown on the display. No display scripting is required for this strategy. It
consists of one Digital Input Block, one Digital Output Block, and a Display Block, as
shown in the next figure. The “FEEDBACK” digital input comes from a set of auxiliary
contacts located on the starter relay. The Result ( R ) of FEEDBACK is connected to
Input 1 of the Display block. Input 1 of the Display Block is connected to the input of the
Command block.
Figure 5 .21.
Strategy blocks for
Discrete Device
Control
The command to start and stop the pump will come from a Display Block input. The
connection is made from the Display Block input to the Digital Output Module.
State Tables representing the appropriate commands must be added to the State Table file
in the State Table block. They can be inserted at any point in the file, however, care must
be taken not to embed them in an existing State Table. The State Tables for this example
are shown below:
Figure 5 .22.
State Tables, pump
on/off control
fbD, 8, "????????" /* Pump contact position*/
{
0, "PUMP OFF";
1, "PUMP ON";
}
comD, 8, "????????" /* Pump command*/
{
0, "TURN OFF";
1, "TURN ON";
}
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