Schneider Electric Implementation

Modbus TCP/IP for Schneider Electric

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

Real-Time

Protocol Overview

Modicon M580 has native Modbus TCP server capability. M340 requires BMXNOE0100 Ethernet module. Unity Pro provides MSTR instruction and Animation Tables for Modbus TCP client operations.

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.

Schneider Electric Hardware Requirements

Compatible Communication Modules

M580 integrated Ethernet (built-in server)

BMXNOE0100 (M340 Ethernet)

BMXNOE0110 (M340 Ethernet/IP + Modbus TCP)

BMXNOR0200 (Remote I/O with Ethernet)

Wiring Details

Network Setup

Dual Ethernet ports on M580 for redundancy. Configure via Control Expert. Port 502 Modbus TCP standard.

Schneider Electric Software & Programming

Function Blocks & Instructions

MSTR (Modbus TCP client)

READ_VAR/WRITE_VAR (Unity Pro)

Animation Tables (automatic polling)

Modbus TCP server (built-in M580)

Schneider Electric Code Example

// M580 built-in server - no code needed
// Map %MW to Modbus registers automatically

// MSTR Client:
MSTR(
  Control := MSTRControl[0..7],
  Data := MSTRData[0..19]
);
// Control[0] := 1 (Read)
// Control[1] := 1 (Slave address)
// Control[3..4] := 40001 (Register)
// Control[5] := 10 (Count)

Schneider Electric-Specific Implementation Notes

M580 is native Modbus TCP server - no programming required, %MW registers directly accessible. Animation Tables provide automatic cyclical polling. GEST_STATUS for error diagnostics. Supports 64 simultaneous client connections on M580.

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

Siemens Allen-Bradley Mitsubishi Schneider Electric Beckhoff ABB Rockwell

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

Alternative Protocols

Related Standards

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