The hardware of an automation system can be selected, but its behavior is defined by software: which valve opens under which condition, which interlock stops a motor, at which step a sequence waits. A well-written control application should be readable, testable and easy for another engineer to maintain years later. Our programming service is carried out with that goal, on international standards.

Standard
IEC 61131-3: FBD, ST, SFC
Platforms
ABB AC 800M, AC 800F, AC500; Advant AC 410/450 and AC 110/160
Output
Control application, type-circuit library, test records, source backups
Approach
A library that is as hardware-independent as possible

The standard: IEC 61131-3

The IEC (International Electrotechnical Commission) defines many international standards. IEC 61131-3 is the standard that defines how controllers used in industry are programmed. We work only with standards-compliant hardware and software, so the application you receive does not depend on a single vendor or a single engineer.

The languages we use

  • Function Block Diagram (FBD): a graphical language in which signals flow between blocks; a natural fit for measurement, regulation and PID loops, and logic that operators can also follow.
  • Structured Text (ST): a text language, the most efficient choice for algorithmic work such as calculations, arrays and data handling, and state machines.
  • Sequential Function Chart (SFC): built from steps and transitions; it shows sequence logic clearly, such as start-up and shutdown sequences and ordered process steps.

We move between these languages according to the process to be controlled and the needs of your plant, and use them together within one application.

Our type-circuit library

We prepare our type-circuit library to be as hardware-independent as possible. Repeating functions such as motors, valves, measurements and PID loops are written and tested once and then used in every project with the same behavior. You can also use this library for your own program additions, which shortens the time needed and lets operators see the same behavior in every unit.

The programming process

  1. Functional descriptionThe P&ID, I/O list and operating logic are turned into a written functional description; every open question is settled at this stage.
  2. ImplementationControl logic, alarm structure and operator interface are built from library blocks; the naming standard is fixed from the start.
  3. Simulation and FATThe logic is tested against documented scenarios with simulated inputs and outputs, without the plant.
  4. Site commissioningLoops are verified one by one and sequences as a whole on site; fine tuning follows operator feedback.
  5. HandoverSource code, backups, a change record and usage notes are handed over to operations.

Which systems do we program?

System 800xAAC 800M controllers and the integrated operator environment.Freelance DCSAC 800F and AC 900F controllers with an integrated engineering environment.AC500 PLCA compact and scalable PLC range.Advant DCSProgramming and maintenance for AC 410, AC 450, AC 110 and AC 160.

You can take programming as part of a DCS installation project, or as a separate service for changing, improving or extending an existing system. For how an I/O list should be prepared see our I/O list article; for platform choice, PLC or DCS? helps.

Frequently asked questions

Can you take over and develop an existing program?

Yes. We first read the existing application and document its structure and risky points; then we make the change or extension in a controlled way, leaving a path back.

Can I buy programming on its own?

Yes. We can take programming even when hardware and panels are in the scope of you or another contractor; the interfaces are defined in writing.

Does the source code belong to me?

The source code and backups of the delivered application are part of the handover package, so maintenance does not depend on one person.