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Siemens Implementation

PROFINET for Siemens

PROFINET is an open Industrial Ethernet system maintained by PROFIBUS & PROFINET International (PI). It uses standard Ethernet alongside Real-Time (RT) communication, with Isochronous Real-Time (IRT) available on Conformance Class C devices for demanding synchronized applications.

Type: Industrial EthernetSpeed: 100 Mbps commonly; Gigabit options are specifiedReleased: 2001Organization: PROFIBUS & PROFINET International (PI)
Depends on the selected physical layer
Bandwidth
Controller and project dependent
Max Nodes
100 m per copper channel; fiber depends on type
Max Distance
Yes
Real-Time

Protocol Overview

PROFINET is Siemens' native protocol. S7-1200/1500 have integrated PROFINET controllers. TIA Portal provides Hardware Configuration for graphical device setup with GSD file import.

When to Use PROFINET

Choose PROFINET when the selected controllers and field devices support the required conformance class and profiles, and when cyclic I/O, diagnostics, topology, safety, drives, or synchronized motion are part of the system requirement.

Siemens Hardware Requirements

Compatible Communication Modules

Integrated PROFINET interface (all S7-1200/1500)
CP 1616/1626 (PC PROFINET interface)
Scalance X switches (RT/IRT support)
PROFINET I/O devices (ET200SP, ET200MP)

Wiring Details

Network Setup

100Mbps/1Gbps Ethernet. IRT requires Scalance switches with PROFINET support. Topology: line, star, ring.

Configuration

Import GSD files in TIA Portal. Drag devices from hardware catalog to network view. Auto-configure I/O addresses.

Siemens Software & Programming

Function Blocks & Instructions

Built-in I/O access (mapped automatically)
PNIO_SEND/PNIO_RECV
D_ACT_DP (activate/deactivate device)
GET_IM_DATA (device identification)
RDREC/WRREC (read/write records)

Siemens Code Example

// Automatic I/O mapping
// Input: %I0.0 from ET200SP DI module
// Output: %Q0.0 to ET200SP DO module

// Manual acyclic read:
RDREC(
  REQ := TRUE,
  ID := 16#0100,  // Hardware ID
  INDEX := 123,
  MLEN := 20,
  RECORD => ReadBuffer,
  => DONE => Done
);

Siemens-Specific Implementation Notes

Native Siemens protocol with deepest integration. Supports IRT (Isochronous Real-Time) for motion control with 31.25μs cycle times. Automatic topology detection. Diagnostics integrated in TIA Portal. Supports PROFIsafe for safety I/O.

Technical Specifications

Physical Layer

  • Physical Layer: IEEE 802.3 Ethernet
  • Cable Type: Cat5e/Cat6 Ethernet, fiber optic
  • Topology: Line, Star, Tree, Ring
  • Power Over Cable: No

Data Layer

  • Data Link: Real-Time (RT) and Isochronous Real-Time (IRT)
  • Encoding: Binary
  • Error Detection: CRC-32
  • Frame Size: 1500 bytes (MTU)

Performance

  • Scan Time: RT update times: 250 µs to 512 ms
  • Deterministic: Yes
  • Real-Time: Yes
  • Cycle Time: IRT can reach 31.25 µs on supported CC-C devices

Certification

  • Certification Required: Yes
  • License Cost: No PROFINET technology licence fee; product certification and testing still apply
  • Version: V2.4

Advantages & Disadvantages

Advantages

  • All conformance classes include real-time data exchange, alarms, diagnostics, and topology support
  • Conformance Class C adds IRT for synchronized applications
  • Standard Ethernet and PROFINET traffic can share a network when it is engineered correctly
  • Profiles such as PROFIsafe and PROFIdrive extend the base protocol for defined application needs
  • Copper, fiber, and other specified physical-layer options support different plant environments
  • PI certification provides an interoperability test path for products

Disadvantages

  • Capabilities vary by conformance class, optional feature, profile, and exact device
  • IRT requires compatible Conformance Class C hardware and an engineered network
  • Copper channels are limited to 100 m between endpoints without another active node
  • Device naming, GSDML files, topology, update times, and diagnostics all require commissioning discipline
  • Product certification and test-lab work add effort for device manufacturers

Common Use Cases & Applications

High-speed manufacturing lines
Motion control applications
Process automation
Automotive manufacturing
Robotics integration
Safety-critical applications

Adoption & Ecosystem Context

Adoption LevelEstablished global PI standard
Primary-source market sharePI does not publish a primary-source percentage
Geographic PresenceGlobal vendor and user ecosystem
Primary Industries
AutomotiveManufacturingProcess IndustriesPackagingMaterial Handling

Supported Message Types

Cyclic data
Acyclic data
Alarms
Diagnostics

Supported PLC Brands

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