The FLSmidth engineering standard is called Adaptable Control Engineering SYStem = ACESYS.
ACESYS follows an object-oriented design philosophy to describe the control block, operator view, data treatment and visual behaviour of a device/equipment in well-defined manner.
The ACESYS have been continuously developed over the years, taking advantage of our experience in the Cement and Minerals industries, and always expanding the system as the technology has allowed.

ECS/ACESYS PLC standard function block library
  • General
  • Design Principles
  • Program Structure

Why Standardize?

ECS/ACESYS™ is a generic programming standard developed by FLSmidth defining control objects, data structures, and program structures needed to implement an efficient process control system based on distributed architecture using advanced process controllers. 

The ECS/ACESYS package consists of several standard programs and pictures (faceplates) for use as a combined set of basic functions for control and monitoring of a modern plant of today.

Benefits of standardization

Using a strong standard will provide the following advantages:
  • Minimize engineering time
  • Tested and validated modules
  • Easy to use
  • Pre-documented 
  • Simple testing 
  • Uniform, flawless code 
  • Independent of specific programmer


Each ACESYS block consists of:

  • Program function block and associated program
  • Faceplate for the object
  • Dialog Faceplate
  • Different sub Faceplates
  • Simulator Faceplates
  • Help look-up
  • Design manual


Faceplate Layout:  

ACESYS Faceplate Details  

   1) Tag code and Description

   2) Actual Status

   3) Different data - depending of selected tab

   4) Tab Select

   5) Info faceplate

   6) Interlock faceplate

   7) On-line Help

   8) Close Button




Control Principles

For a specific process controller, ACESYS constitutes a comprehensive collection of subroutines. All controlled units are treated as objects in the program. This ensures that the basic functions are of a well-proven design and that changes to the behaviour of an object can be done in a safe way. All I/Os and internal variables are named in a structured way in order to avoid the need for detailed knowledge of the physical addresses. Furthermore, a textual description is attached to all names to increase readability. The program is well documented with headlines and descriptions.

Closed loop control is enabled with modular PID controller software allowing application of simple as well as very complex loop functions.

The process is divided into a number of departments each describing main process equipment like the kiln, the raw mill etc. Each department is in turn organised through Groups, Routes and Units (Motors etc.), each of which will be described below.

A department is divided into Groups representing the logical control sequences needed for the control of the department. A Group controls a number of Routes and/or motors and other units and typically makes one separate section of the department e.g. a clinker transport or raw mill hydraulic.

In the ECS-system alarms from units within a group or route that are stopped can be suppressed. It is possible individually to configure alarms not to be suppressed.

Program Structure

The following diagram illustrates the logic structure of the process controller program:

 ACESYS PLC Prorgam Structure 

A unit can be a Unimotor, Bimotor, Motorgate, Positioner, Valve, Extended Motor, Extended Gate, Extended Valve, Recipe or Compressor Sequence. These units must be associated to a group or a route. It is possible to select individual for each unit if it shall pass alarm status to the group.
Digital and analog alarms are all associated to a Group or a Route. Each of the alarm objects can be individually selected to pass alarm status to the Group or Route.