Abelko IMSE WebMaster Pro - 15.9 Example - solar collector

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15 - Graphical programming
15�9 Example - solar collector
In the next example, we will program the control system for a solar collector pump. It will work like
this: If the temperature in the solar collector is three degrees higher than the temperature at the
bottom of the storage tank, the pump will start running and continue until the dierence drops
to two degrees. The pump will also be exercised on the basis of a calendar. We will need two vari-
able parameters. One for the dierential temperature and one for the hysteresis. These parameters
already exist if you followed the steps in the conguration pages. In the example they are called Di.
temp Sunpanel and Hysteresis Sunpanel.
Conguring a parameter is easy – open Settings/Advanced and Parameters. A list appears showing
all congured parameters – script parameters have a pale blue background and user parameters
have a pale yellow background. Free parameters have a white background. They are named Data 15,
16, etc.
Select the rst free parameter by giv-
ing it a name (Di.temp Sunpanel),
enter a value (3), a unit (K) and the
number of decimal places (1). Repeat
these steps for another parameter,
calling it Hysteresis Sunpanel, giving
it a value of 1 and using the same unit
and decimal places. Remember to
click the Save button before you leave
the page.
To change a parameter value simply enter a new value and click Save. You can also add the param-
eter to a conguration page as described in the previous section. You can make changes directly in
the conguration page.
As well as these two parameters, we will need two temperature sensors. One is in the solar collector
on the roof and the other is at the bottom of the storage tank. And we also need a digital output
and an pump exercise calendar. Set this all up before you continue.
Open graphical programming. Type Sunpanel under New program name and click Create.