Simulator Components

A TRAX simulator is comprised of five major components: process models, control logic, human-machine interface (HMI), input/output (I/O), and the Instructor Station.

Learn about the first four elements here, and then take a detailed look at why the Instructor Station is such an important part of the simulator.

Simulator in progress

Process Models

TRAX builds simulator process models using the ProTRAX simulation software. Each plant-specific simulator is configured to exactly match the simulated plant, and the individual components of a model are tailored to the specific plant, resulting in a simulator that truly represents plant operation.  The process models include the main thermo-hydraulic processes, as well as associated electrical buses and auxiliaries as required for the specific operation of the plant.

TRAX specializes in providing high-fidelity, engineering-grade models. To be a “high-fidelity” model, three items must be true:

  • Equations describing component behavior are based on conservation of mass, energy, and momentum (first principles) along with well-accepted constitutive equations for heat transfer and flow.
  • The plant model accurately represents the configuration of the actual plant.
  • Each component’s parameters accurately represent the corresponding component in the actual plant.

In addition to our high-fidelity modeling, we also work with our customers to identify the parts of the process that can be adequately modeled using medium-fidelity or low-fidelity techniques, such as simplified modeling or loopbacks.  This enables TRAX to provide a cost-effective simulation solution, customized to the project requirements, that will provide excellent training value.

Control Logic

The most common type of simulator is a virtual system.  In a virtual system, TRAX exactly duplicates the controls in the plant with the controls in the simulator.  The plant files are downloaded to the simulator with no manipulation, translation, or special interfaces required.  TRAX runs the control logic on a standard computer instead of the hardware controller used in the plant, resulting in the exact same functionality.

TRAX’s fully emulated systems use a translation of the plant control logic and graphics into the simulator environment. This translation is sometimes performed with an automatic translation program, and sometimes TRAX will manually build the control logic using third-party software.

Human-Machine Interface (HMI)

In a similar fashion, the HMI graphics used in the plant are either loaded directly onto the simulator (virtual) or translated to the simulator (emulated).  The HMI on the simulator is a precise reproduction of the HMI in the plant, in both functionality and appearance. Operational skills learned through TRAX simulator training are fully transferable to the plant.

TRAX ensures control room hard panels are also represented in the simulator. These emulations combine realistic photo-quality screen displays with dynamic functions.

In addition, TRAX provides local operation screens that allow the operator to perform remote operations. This replicates open/close or start/stop devices that are operated by a roving operator.


TRAX prepares an interface model to represent the DCS field I/O connections between the control system and the simulated process models.  This model provides simple operator feedback for most I/O signals.