Phonetics Sensaphone SCADA 3000, User Manual

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Figure 5: Template program
Referencing SCADA 3000 I/O Points
Every I/O point or component that is placed on the Real-time screen is assigned a unique tag-
name which is made up of the
Component Name
and the
Property Name
. The
Component Name
is
based on the type of component used on the screen along with a number. Each time that com-
ponent is used on the screen the number will increase. For example, a DataPointValue compo-
nent gets the name DataPointValue# . The # part of the name increases by one each time a new
point is added to the screen. The
Component Name
can be viewed on the property form when
the component is selected. I/O points are referenced in the script program using a combination
of the Component Name and the Component Property . The properties of a component are those
listed on the property form. The format for referencing I/O points or components in your
script program is
ComponentName.ComponentProperty.
As an example, if you were going to reference the numerical value of an Input on your Real-
time screen you would use the DataPointValue component. The property you would read or
write would be the value property. So the complete tagname would be DataPointValue1.value .
You use the tagnames to read and write to I/O in your Distributed Control program.
Sample Application:
Suppose you have two SCADA 3000 units, one at Location A, the other at Location B. At
location A there is a water tank with a level transducer connected to the SCADA 3000. At
Location B there is a pump, which is connected to an output on the SCADA 3000. When the
pump is turned on at Location B, water will be pumped into the tank at Location A.
A host computer is set up so that it is continuously online with both SCADA 3000 units. A
Real-time screen is created, which displays the level in the tank and the On/Off status of the
pump. See below.
Figure 6: RT Screen
22-3
Chapter 22: Distributed Control using Visual Basic