Script Tags

Script Tags provide a highly configurable way to define calculation and event raising tags.

Script tags can be written in:

• C#
• FLEE (Fast Lightweight Expression Evaluation) - more info

A number of pre-configured script tags exist to perform the following functions:

• Accumulator Calculator
  Calculates the accumulated result of a monitored process tag for a given period (e.g. a day).

• Aggregation Calculator
  Periodically calculate an aggregation of a process tag.

• Average Calculator
  Periodically calculates the average value of a process tag.

• Delta Calculator
  Calculates the delta between the value of two input tags.

• Delta with Offset Calculator
  Calculates the delta between the value of two input tags, then applies an offset.

• Energy Based Availability Calculator
  Energy-Based Availability (EBA) is the ratio of actual to expected energy production.

• Gas Velocity Calculator
  Calculates gas velocity using flow rate and pressure.

• Normalized Deviation Calculation
  Calculates the normalized deviation of a process value.

• Ratio Calculator
  Calculates the ratio and between two input tags.

• Time Based Availability Calculator
  Time-Based Availability (TBA) is an energy expression denoting the ratio of a time-period (e.g. a day) when power is available. It does not discriminate the cause of downtime (e.g. a deliberate stop for maintenance, no/low wind conditions).

• Time Based Delta Calculator
  Monitors the rate of change of a process tag over a time period.

• Turbine Status
  A turbine has three basic power-production states: 1. Power; 2. No Wind; 3. No Power.

• Turbulence Intensity Calculator
  Turbulence Intensity (TI) is a measurement of wind speed turbulence. It is the ratio of wind speed StdDev to Mean.

• Turbulence Intensity Forecast Calculator
  Turbulence Intensity Forecast (TI) is an measurement of wind speed turbulence derived from forecasted Wind and Gust Speed (rather than observed wind speed variance).

• Unit Converter
  Convert process value from one unit to another.

• Bad Data Detection
  Data quality check that raises alert if monitored tag returns NaN or has a 'bad' status.

• Channel Deviation Detection
  Checks for deviation in output from a sensor with two data channels. An alert indicates that one or both of the channels is unreliable. The method is to regularly compare Channel A and Channel B and check if difference is within acceptable instrument error tolerance. Default configuration is to check 24hr average difference 4 times per day.

• Flatline Detection
  Script tag that checks for flatlining data (i.e. process tags where the tag may be updating regularly, but the sensor value is not changing).

• Frozen Signal Detection
  Script tag that periodically ensures that newer values are being received for a tag.

• Equipment Running Status Monitor
  Monitors the running status of a piece of equipment and triggers and resets events when the status changes.

• Fleeting Excursion Monitor
  Script tag template for monitoring sensors such as acoustic sand probes that can generate fleeting excursions.

• Hi/Lo Limit Monitor
  Performs a Hi/Lo limit monitor check.

• Limit Monitor
  Script tag that periodically monitors a process tag value against a limit using MIN/MAX aggregated data.
  Use the FleetingExcursionMonitor template if you require a high degree of accuracy.

• Limit Monitor 1 Precondition
  Limit monitor that will only trigger or reset an excursion event if a precondition tag value check is met.

• Limit Monitor 2 Precondition
  Limit monitor that will only trigger or reset an excursion event if two precondition tag value checks are met.

• Limit Monitor 3 Precondition
  Limit monitor that will only trigger or reset an excursion event if three precondition tag value checks are met.

• Logic Gate Alert
  An alert that can be used to summarise the status of multiple alerts using an AND or OR operator.

• Time Based Delta Monitor
  Monitors the rate of change of a process tag over a time period.

• Value Change Monitor
  Monitors a tag and emits an event every time the value of the tag changes.

The Data Core Admin UI shows information related to the processing of an individual Script Tag via the “Info” and “Additional Properties” icons.

The Data Core API also exposes information related to all Script Tags for a data source.

• [DataCoreAdminUrl]/datacore/api/diagnostics/scripting/[dataSourceName]