Thanks a lot for keeping my brain-cells moving. You guys Rock!
I think I finally got my RPM detector (and recorder) to work. I learned a lot from reading many posts on the subject as well as reviewing some of the sample code found here and other sites. I wasn't sure what to use, either HSCs or TSI - much less, how to use them. It is the first time I venture into reading RPMs using PLCs.
Bottom line is that I rather use TSI for precision but I want to read 4 sensors with a single PLC; yet, I only have one TSI available in the Function files tree - Unless I can create more and I don't know how.
The PLC will be connected to a laptop running a mini-SCADA data collection system for later analysis specially developed for this test - to read just 4 analog inputs during the initial 5-minutes of every startup. I am not planning to be present when they start those pumps which typically occurs at night when power is cheap.
I plan to follow up this thread with a Lessons-Learned update where I will explain what I did and how, while providing the sample code used hoping others will find useful. The intended audience of the update will not necessarily be those experts on the subject, but rather those that in the future will ask questions about this very same topic.
- J R Martinez