Thursday, July 24, 2014

Repost: What is SCP270?

Guest Post by Janet Parker

What is SCP270?

SCP270 is a “virtual stimulation” of the Foxboro I/A Series DCS Control Processor (CP) combined with modeling capability from DYNSIM. SCP270 software is built from the same CP270 algorithms and communication infrastructure of I/A Series control processors. All operational and engineering applications, processes, and equipment that run with I/A Series control systems, run the same way with SCP270 software.

It is important to understand the difference between “full stimulation,” “virtual stimulation” and emulation. Full stimulation replaces the sensors with a software model that pushes the equivalent 4 – 20 mA signal into the Fieldbus Modules (FBM)/control processor using the same communication protocols, processor algorithms, and Human Machine Interface (HMI) as the real unit. This type of activity is good enough for “end-to-end” safety validation to ensure the control system is 100% functional from a hardware standpoint. Virtual stimulation replaces the sensors with a mathematical model and the controllers and FBMs with a simulation that is derived from the identical algorithms and communication protocols as the actual controllers. When used in the context of dynamic simulation, emulation can be considered a mathematical model built by a separate company based on documentation and controller observation. It typically extends to the HMI and is only useful for low quality training, not for control logic checkout or validation.

SCP270 software also fully simulates the I/A Series ladder logic, sequence of events, and motor drive actuator, which all normally execute in the FBM. Controls deploy to an SCP270 application exactly as they do to a real CP for all I/A Series configurators (Integrated Control Configurator, I/A Series Configuration Component, and Foxboro Evo) without modification.

All Dynamic Simulation Suite (DSS) products, including SCP270, are bundled with the DSS graphical user interface (GUI), the simulation executive, and equipment modeling capability. A single GUI is used for model building and instructor operations. SCP270 provides a subset of the DYNSIM equipment modeling library. SCP270 is typically delivered with a turnkey Operator Training Simulator (OTS) from Invensys or for use by I/A Series users for DCS control checkout or control logic checkout.