Valve management

Various applications within the AVEVA Pipeline Operations for Liquids suite contain the concept of valves. These valves are used to determine a pipeline’s current state and execute various actions. To provide a centralized location for all valve-specific configurations, AVEVA Pipeline Operations for Liquids supports the creation of independent objects within the RealTime database (RTDB)'s valve table. Valve objects represent physical, logical, and synthetic valves within a pipeline and are used by other AVEVA Pipeline Operations for Liquids applications.

The Valve application provides enhanced state management capabilities for polled AVEVA Enterprise SCADA points represented as status or multistate records.

Key Concepts

• Configuration and runtime data for a valve is contained in the valve table.

• A valve record is one of three types:

  • Physical. The valve record is associated with a status or a multistate record. The state of the valve depends directly on the state of the status or multistate record. The Controller can issue commands to the valve record, which are forwarded to the status or the multistate record.

  • Logical. The valve record is not associated with a status or a multistate record. The valve record has a parent relationship to one or more child valve records. The state of the valve depends on the combined state of the child records. No commands can be issued to the valve record.

  • Synthetic. The valve record is associated with a status or a multistate record. The valve record has a parent relationship to one or more child valve records. The state of the valve depends on the combined state of the child records. The Controller can issue commands to the valve record, which are forwarded to the status or the multistate record. There are two types of synthetic valves: Synthetic Programmable Logic Controller (PLC)-based valves and Synthetic AVEVA Enterprise SCADA host-based valves.

• A valve record is an extension of status or multistate records that provides additional state information and processing rules that are particular to the valve type of digital device.

• A valve record is processed only when an update occurs to either the associated status or multistate record (for Physical type) or to a child valve record (for Logical or Synthetic type).

Key Tasks

• Configuration of the valve record.

• Understanding the relationship of a valve or combination of valves to the status or multistate where the valve control is handled.