How do I Calculate the Number of Trains Running using Train Speed (RPM)?

Question asked by Muthulingam-EnQuest on Jun 27, 2019
Latest reply on Jun 27, 2019 by TimCarmichael

Hi guys,

I would like to Calculate the Number of Trains Running using Train Speed (RPM)?

Below is the PI Performance Equation that I came up with:

Event=MY.SEA.49SI240B.PV, (If('MY.SEA.49SI240B.PV'>0 then 1 else 0)+If('MY.SEA.49SI340B.PV'>0 then 1 else 0)+If('MY.SEA.49SI440B.PV'>0 then 1 else 0))

The tags are Train Speed Tags:

• Point Type                   : Float32
• Unit                             : RPM
• Bad State                     : Unit Down

The Expected Results are:

• is 0 if none of the rains are Running
• is 1 if only the 1 Train is Running
• is 3 if only 2 of the Trains are Running
• is 3 if all the 3 Trains are Running

However my formula is not yielding any results and are currently in the "Pt Created" State:

My Questions:

1. Is my Syntax Correct? If not, please correct it or propose a new Equation.
2. Can PI automatically detect "Unit Down" value as String and perform the calculation even if 1 or all the Tags are in "Unit Down" value? Currently 2 of 3 of the Trains are showing "Unit Down" status
3. Can I choose not to have either an Event based Trigger or a Time Based Trigger for a PI Performance Equation? If yes, how?

Ganesh Supromaniam

Best regards,

Muthulingam Ramiah

Senior Systems Consultant