With many of the great functions of the Watlow F4 controller, I thought it would be nice to have a quick routine to create a ramping profile programmatically. Or how about getting a quick tune up for the load conditions under your desired temperatures, using Watlow's Autotuning feature?
I created two LabView VIs (Virtual Instruments) using standard National Instruments GPIB 488.2 commands after purchasing the GPIB-to-Modbus adapter from ICS Electronics (www.icselect.com). The VI library purchased from ICS was great for doing single function calls and using it as Top-Level VIs, but I had a need to drop them in as subVIs and create ramping profiles on the fly for my current desired application.
These VIs work great as either a standalone application, or as a sub-level function call in your larger application. Watlow_RampProfiler.vi creates a single ramping profile named PROFILE1.
The following information is necessary to create a ramping profile in this VI:
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Ramping Rate—in degrees celsius per minute
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Final Temperature—the temperature that the profile will ramp up to, in degrees celsius
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PID Select—will use the chosen PID settings, previously stored in memory (PID Set 1 to 5)
This VI will also stop any running profiles or set points by running it with the boolean in the false ("Terminate Profile") condition.
You can also utilize the F4's Autotuning procedure with Watlow_AutoTune.vi. This VI will automatically start the built-in routine given the inputs of percent of set point (see F4 manual), set point, and PID Select to store the settings in.
kpupuhi@sandia.gov
You need this trick if: You need to quickly setup a ramping profile for your Watlow Series F4 controller, or want to Auto-Tune the controller programmatically without going through any of the menus.