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PROFIBUS

Process Field Bus - established fieldbus standard for factory and process automation. Predecessor to PROFINET.

Type: FieldbusSpeed: 9.6 kbps to 12 MbpsReleased: 1989Organization: PROFIBUS & PROFINET International (PI)
12 Mbps max
Bandwidth
126
Max Nodes
1200m (at lower speeds)
Max Distance
Yes
Real-Time

Protocol Overview

Process Field Bus - established fieldbus standard for factory and process automation. Predecessor to PROFINET.

When to Use PROFIBUS

Choose PROFIBUS for existing installations, process industry applications, or when integrating with legacy Siemens systems.

Technical Specifications

Physical Layer

  • Physical Layer: RS-485, MBP (Manchester Bus Powered)
  • Cable Type: RS-485 twisted pair, fiber optic
  • Topology: Bus, Tree
  • Power Over Cable: No

Data Layer

  • Data Link: Token passing
  • Encoding: NRZ
  • Error Detection: Hamming distance HD=4
  • Frame Size: 244 bytes

Performance

  • Scan Time: 1-10ms typical
  • Deterministic: Yes
  • Real-Time: Yes

Certification

  • Certification Required: Yes
  • License Cost: Device certification required
  • Version: DP-V2

Advantages & Disadvantages

Advantages

  • ✓Proven reliability (35+ years)
  • ✓Deterministic real-time performance
  • ✓Large installed base (60M+ devices)
  • ✓Excellent diagnostics
  • ✓Supports intrinsically safe (PROFIBUS PA)
  • ✓Multiple physical layers
  • ✓Interoperable devices

Disadvantages

  • ✗Legacy technology (being replaced by PROFINET)
  • ✗Lower speed than Ethernet options
  • ✗Complex installation and commissioning
  • ✗Requires terminators and careful grounding
  • ✗More expensive than Modbus
  • ✗Limited future development

Common Use Cases & Applications

Process automation (oil, gas, chemicals)
Legacy system integration
Hazardous area installations (PA)
Discrete manufacturing
Drive control systems

Industry Adoption

Adoption LevelHigh (declining)
Market Share10-15% (declining as PROFINET grows)
Geographic PresenceWorldwide, strongest in Europe
Primary Industries
Process IndustriesOil & GasChemicalManufacturing

Supported Message Types

DP (Decentralized Peripherals)
PA (Process Automation)
FMS (Fieldbus Message Specification)

Supported PLC Brands

SiemensABBSchneider Electric
Phoenix Contact
Pepperl+Fuchs
Endress+Hauser

Protocol Comparisons

PROFIBUS vs PROFINET

PROFINET is the modern Ethernet successor to PROFIBUS fieldbus

View Detailed Comparison →

Quick Links

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