Troubleshoot System Wide Meter Accumulation Problem

The Problem:

A major Oil Pipeline was having intermittent problems with meter accumulators at the S.C.A.D.A. Host.  The monthly meter totals used for billing were correct, but on occasion the telemetered value would roll back and then jump forward, generating numerous line balance alarms.

The challenge with this issue was that it was not known if the problem existed in the field devices or the host system, and the occurrences were brief and intermittent.   To compound the issue even more, a field upgrade of RTU's and flow computers had been ongoing over the previous year.  DCI Technologies was brought in to provide an independent analysis of the situation.

The Solution:

Data was collected from the S.C.A.D.A host logs and parsed into a database.   Further data on each meter station was collected including RTU's, Flow Computers, firmware versions and installation dates were also entered into the Database.  Approx. 60,000 records in total were accumulated.  Analysis was done using Seagate's Crystal Reports combined with some custom code.  It soon became clear that it was a firmware version of the RTU that was causing the rollbacks.  The total analysis job was completed in two weeks.  The RTU Manufacturer was then able to identify the specific issue and start work to rectify the problem.