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Beckhoff Implementation

Modbus TCP/IP for Beckhoff

Ethernet-based variant of Modbus using TCP/IP. Combines simplicity of Modbus with speed and scalability of Ethernet.

Type: Industrial EthernetSpeed: 10/100/1000 MbpsReleased: 1999Organization: Modbus Organization
1 Gbps capable
Bandwidth
Unlimited (network dependent)
Max Nodes
100m per segment (with switches: unlimited)
Max Distance
No
Real-Time

Protocol Overview

Ethernet-based variant of Modbus using TCP/IP. Combines simplicity of Modbus with speed and scalability of Ethernet.

When to Use Modbus TCP/IP

Choose Modbus TCP/IP for SCADA systems, plant-wide networks, remote monitoring, or when integrating industrial equipment with IT systems.

Technical Specifications

Physical Layer

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

Data Layer

  • Data Link: TCP/IP
  • Encoding: Binary
  • Error Detection: TCP checksum
  • Frame Size: 1500 bytes (MTU)

Performance

  • Scan Time: 1-10ms typical
  • Deterministic: No
  • Real-Time: No

Certification

  • Certification Required: No
  • License Cost: Free (open standard)
  • Version: Current

Advantages & Disadvantages

Advantages

  • ✓High speed (up to 1 Gbps)
  • ✓Uses standard Ethernet infrastructure
  • ✓Unlimited nodes and distance (with switches)
  • ✓Easy IT integration
  • ✓Simple protocol (Modbus heritage)
  • ✓Open standard and free
  • ✓Remote access capability

Disadvantages

  • ✗Not deterministic (not real-time)
  • ✗No built-in security (requires VPN/firewall)
  • ✗Higher latency than dedicated fieldbuses
  • ✗Requires managed switches for large networks
  • ✗No device profiles or configuration tools

Common Use Cases & Applications

SCADA systems
Plant-wide data collection
Building management systems
Remote monitoring
Enterprise system integration
Large distributed systems

Industry Adoption

Adoption LevelVery High
Market Share25-35% of industrial Ethernet
Geographic PresenceWorldwide
Primary Industries
Oil & GasWater/WastewaterBuilding AutomationManufacturingEnergy

Supported Message Types

Read Coils
Read Discrete Inputs
Read Holding Registers
Write Single Coil
Write Single Register
Write Multiple Registers

Supported PLC Brands

SiemensAllen-BradleyMitsubishiSchneider ElectricBeckhoffABBRockwell
Phoenix Contact
Wago

Protocol Comparisons

Modbus TCP/IP vs EtherNet/IP

Modbus TCP is simpler and open; EtherNet/IP offers better diagnostics and CIP ecosystem

View Detailed Comparison →

Quick Links

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