Major DCS/PLC Platforms Reference

Platform Overview

ABB Freelance

Key Characteristics

• Compact DCS for small-medium plants
• FBD/LAD primary programming
• File-based engineering (PRT, DMF, CSV)
• BST_LIB (standard) + BST_USER (custom) function block libraries
• MSR points as primary addressable entities
• DigiVis for operator displays
• DIGI protocol for internal communication

Motor Control: IDF_1 + MOT_T1

MOTOR1 Structure (11 signals):
  IN:  AC (auto cmd), PR0 (safety), MA (req auto), MM (req manual)
  OUT: ILK (interlock), RDY (ready), RUN (running), LOC (local), AUT (auto), FLR (fault), SDS (shutdown)

Automation Approach

• PRT file templating (text replacement)
• CSV project parsing/generation
• No public API (file manipulation is the standard approach)
• Checksum can be set to 0; Freelance recalculates on import

Siemens PCS 7

Project Hierarchy

PCS 7 Project
  +-- OS (Operator Station - WinCC)
  +-- AS (Automation Station - S7-400/1500)
  |     +-- CFC Charts (Continuous Function Charts)
  |     +-- SFC Charts (Sequential Function Charts)
  +-- Hardware Configuration
  +-- Plant Hierarchy (technological view)
  +-- Process Tag Management

Motor Control: MotL Block (APL)

Inputs:  ModLiOp, AutModOp, ManModOp, FbkRun, Protect, Intlock01, CmdStrt, CmdStop, MonTiRun, MonTiStp
Outputs: ModLiOp_Out, StartOut, RunOut, StopOut, Trip, SwiToLoc

Other APL blocks: MotR (reversing), MotSpdL (speed), VlvL (valve), PIDConL (PID), Intlk02/04/08/16 (interlock), MonDi/MonAn (monitoring)

File Formats

• .s7p / .s7l - S7 project/library
• .pdl - WinCC display
• .xml - SimaticML block export (proprietary schema)
• .aml - AutomationML (PCS 7 V9+)
• .scl / .awl - ST / IL source

Automation: TIA Portal Openness API (.NET)

using Siemens.Engineering;
TiaPortal tia = new TiaPortal(TiaPortalMode.WithUserInterface);
Project project = tia.Projects.Open(new FileInfo(@"Project.ap17"));
PlcSoftware sw = device.GetService<PlcSoftware>();
sw.BlockGroup.Blocks.Import(new FileInfo(@"Block.xml"), ImportOptions.Override);

Capabilities: create projects, import/export blocks as XML, create tags, generate HMI screens, compile, download.

HMI: SiVArc

Rules-based auto-generation: "For every MotL instance, create a faceplate." Reads PLC structure, generates WinCC elements.

Emerson DeltaV

Architecture

DeltaV System
  +-- Plant Areas
  |     +-- Control Modules (CM) - individual loops
  |     +-- Equipment Modules (EM) - sequences
  |     +-- Phases - ISA-88 batch
  +-- Controllers (M-series, S-series)
  +-- I/O Subsystem
  +-- Module Templates (reusable designs)

Motor Control: DC (Device Control) Block

Inputs:  MODE_BLK.TARGET, IN_D1 (running fbk), IN_D2 (stopped fbk), IN_D3 (fault), IN_D4 (available), INTERLOCK, PERMIT
Outputs: OUT_D1 (start), OUT_D2 (stop), SP_D (setpoint), PV_D (process value)
Config:  IO_OPTS, FBK_STRATEGY, FBK_TIMEOUT

Automation: Class-Based + Bulk Edit

• Module Templates: Define once, instantiate many. Change propagation on template update.
• Bulk Edit: Export to Excel, modify, import back.
• FHX Files: Text-based config format, parseable and generatable.

MODULE TEMPLATE "MT_MOTOR_1SPD" /
  MODULE_CLASS = DEVICE /
{
  FUNCTION_BLOCK "DC-1" / DEFINITION = "DC" /
  { ATTRIBUTE MODE_BLK.TARGET = AUTO ; ... }
}

Tag Structure

Area/ControlModule/FunctionBlock/Parameter
Example: PLANT/M_101/DC-1/PV_D

Honeywell Experion PKS

Motor Control: MOTOR Block

Inputs:  SP (cmd), MODE, INTLK, FB_RUN, FB_STOP, FB_TRIP, LOCAL
Outputs: OP (output), STATUS, ALARM
Config:  FB_TIME (monitor time), STRATEGY

Programming

• CL (Control Language): Proprietary ST-like language
• FBD: Graphical function blocks
• Custom Algorithms (CA): Complex logic

Automation

• CSV/Excel bulk point import
• COM-based API (Experion PKS API)
• OPC DA/UA interface

Cross-Platform Motor Block Mapping

Cross-Platform Function Block Mapping

IEC 61131-3 Support Comparison

Bulk Engineering Comparison