Applications Guide Tracer Graphical Programming - Trane

®
Chapter 5 Cooling tower with variable-speed fan example
Refreshing the TGP editor
If you already have the TGP editor open and you make changes to the
controller configuration, you do not have to close the editor. Use the
refresh function to update the TGP editor. For example, if you are writing
a program and you realize that you need to set up an analog variable, go
to the Rover application to set up the variable. Then return to the TGP
editor and refresh the analog variables to implement the variable you just
configured.
To refresh the TGP editor:
1. From the View menu, choose Refresh.
2. From the Refresh menu, choose the set of data you want to refresh or
choose All. The configuration data uploads to the editor.
Determining a programming approach
Review the sequence of operation to determine the changes that are
required to the cooling tower program in the module that controls the
cooling tower fan. The new sequence of operation calls for modulating
control of the fan. Also, a new module is required to calculate critical performance
parameters for the cooling tower and to control the condenser
water pump. For the purposes of this tutorial, work on the modules in the
following order:
1. Alarms
2. Calculations
3. Cooling tower fan
4. Condenser water pump
Editing the program properties
Set the program properties, including the program name and its run frequency.
Use a run frequency of 30 seconds.
To edit the program properties:
1. Open the cooling tower with two-speed fan program.
2. Save the program under a new name.
3. Open the Program Properties dialog box and set the properties, along
with an updated description of the program.
4. Click OK.
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