MODBUS RS-485 · EASTRON SDM630 · INDUSTRIAL CLOUD

Connect your meters Modbus RS-485 Get Started with the Cloud in 5 Minutes

Eastron SDM630, SDM120, Schneider iEM3155, ABB B23, Carlo Gavazzi EM340 — the Eziwan Gateway reads your Modbus RTU meters and sends all measurements to the cloud, with store-and-forward functionality, alerts, and a REST API.

32 ctrs
via RS-485 port
1 sec
minimum polling
72 h
store & forward
70+
SDM630 registers
SDM630
SDM120
SDM230
iEM3155
EM340
ABB B23
…32 max
Eziwan
Gateway
Cloud

Why Choose Eziwan

No more manual data entry and Excel exports

😤

Manual monthly statement, either handwritten or on a tablet

Automatic data collection every 5 seconds, 24 hours a day

🗃️

Excel and CSV files scattered across different sites, with no reliable history

24-month centralized history, API & automatic export

💸

Proprietary SCADA system for €15,000, including annual maintenance

Eziwan cloud subscription starting at €49/month, all-inclusive

🔌

Standalone meters that cannot be connected to the IT/OT network

RS-485 → 4G or Ethernet, without additional network cabling

🔔

Overages Found on the Electricity Bill

Real-time alerts via text message or email as soon as a threshold is exceeded

🏢

Each site is managed separately, without a multisite view

Unified Multi-Site Dashboard, Fleet Comparison

Commissioning

3 Steps to Connect Your Meters to the Cloud

STEP 01

RS-485 Wiring (A/B)

Connect the meter's RS-485 interface (terminals A+, B–) to the Eziwan Gateway's RS-485 port. A maximum of 32 meters can be daisy-chained over 1,200 m of shielded cable.

# Eziwan Gateway Physical Terminals
RS-485 A+ → Terminal 3 (shielded twisted-pair cable)
RS-485 B– → Terminal 4
GND shield → Terminal 5 (at one end only)
120 Ω resistor → bus ends
STEP 02

Modbus RTU Configuration

In the Eziwan web interface, add a Modbus device with the meter's address (1–247). Select the Eastron SDM630 profile or enter the registers manually.

# Eziwan Web Interface (192.168.1.1)
Protocol: Modbus RTU
Baud rate: 9600 (SDM630 default)
Data bits: 8 / Parity: None / Stop: 1
Device ID: 1 (DIP switch address)
Registers: SDM630 profile (70 reg.)
STEP 03

Real-time data in the cloud

The Gateway automatically sends measurements to the Eziwan cloud via MQTT/HTTPS. Access the dashboards from your browser or integrate them via the REST API.

# Eziwan Cloud REST API
GET /api/v1/devices/{id}/metrics
Authorization: Bearer {token}

# JSON response
{
  "L1_voltage": 230.4,
  "L1_current": 12.8,
  "active_energy": 4521.2, // kWh
  "power_factor": 0.94
}

Compatibility

All your meters are natively supported

Preconfigured profiles for leading brands. Any other Modbus RTU or TCP meter can be added in just a few minutes via the configuration interface.

Eastron SDM630

100A Three-Phase Energy Meter, RS-485 Modbus RTU, 70+ Registers

Three-phase100A70 reg.
Eastron SDM120

45A single-phase meter, RS-485 Modbus RTU, compact DIN-rail enclosure

Single-phase45ADIN
Eastron SDM230

100A single-phase meter with LCD display, up to 32 bus addresses

LCD100A32 addresses
Eastron SDM72D

Bidirectional energy meter, ideal for solar power generation

BidirectionnelSolaire
Eastron SDM220

Single-phase DIN-rail meter, 45 Modbus registers, economy rate

Economic45 reg.

Is your meter not on the list? Contact us — We can add profiles upon request or help you create a custom profile.

Technical Reference

SDM630 Modbus Registers Read by Eziwan

The native SDM630 profile automatically reads these registers. All other SDM630 registers can be added manually.

MesureModbus RegisterUnitDescription
Voltage, Phase 10x0000VL1 RMS Value Urms
Voltage, Phase 20x0002VL2 RMS Value Urms
Phase 3 Voltage0x0004VL3 Urms RMS Value
Phase 1 Current0x0006ARMS Current, Phase L1
Phase 2 Current0x0008ARMS Current, Phase L2
Phase 3 Current0x000AARMS Current, Phase L3
Active power P10x000CWActive power, phase L1
Total Active Power0x0034WSum of Active Powers
Imported active energy0x0156kWhTotal Energy Consumed
Power Factor0x003Ecos φ total (Power Factor)
Mains frequency0x0046HzFrequency (Hz)
Reactive power0x003CVArTotal Q

The SDM630 exposes 70+ Float32 (Big Endian) registers, according to the Eastron SDM630-Modbus v1.5 documentation

Features

Everything You Need for Professional Supervision

Configurable Modbus Polling

Data collection frequency ranging from 1 second to 24 hours. On-demand polling via API. Multiple registers in a single frame to optimize RS-485 bandwidth.

Preconfigured meter profiles

Profile library for SDM630, SDM120, iEM3155, EM340, B23, and more. Add custom profiles by uploading a JSON file through the interface.

Store and Forward

72-hour local buffer on the internal flash memory. If the 4G or Ethernet connection is lost, the measurements are saved and automatically resent when the connection is restored.

Real-Time Threshold Alerts

Set thresholds for exceedances (maximum power, out-of-range voltage, low power factor) with SMS, email, or webhook notifications.

24-Month History

Data is retained for 2 years in the Eziwan cloud. CSV/Excel export, REST API (JSON), integration with Grafana, Power BI, InfluxDB, and Prometheus.

End-to-end encryption

OpenVPN/IPSec VPN between the gateway and the cloud. TLS 1.3 for Modbus data. No incoming ports open on your OT network.

Areas of Application

For each sector, a business use case

🏭
Industrie
Tracking Workshop Consumption
  • Eastron SDM630 meters on each machine/workstation
  • Energy Performance Index (EPI) by product reference
  • Detection of Equipment That Was Not Properly Turned Off (Standby Power Consumption)
  • ISO 50001 Compliance: Automatic Monthly Report
🏢
Tertiary Sector & Construction
Under-billing and re-billing
  • SDM120 per tenant or building section
  • Automatic Generation of Invoices
  • Multi-site dashboard (hotel portfolio, offices)
  • Detection of Excessive Nighttime/Weekend Energy Consumption
Energy & Utilities
Network and Production Monitoring
  • SDM72D Bidirectional Controller for Photovoltaic Panels
  • Tracking the Self-Consumption to Grid Injection Ratio
  • Monitoring UPS Systems, Generators, and Main Power Distribution Panels
  • Compliance with the RED II Directive and RE2020 Regulations
🖥️
Data Centers
PUE and Energy Efficiency
  • Continuous PUE (Power Usage Effectiveness) Measurement
  • Meters by rack, by PDU, by floor
  • Phase-to-Phase Load Imbalance Alerts
  • DEEM (Data Center Energy Efficiency Metrics) Report

FAQ

Frequently Asked Questions About Modbus RS-485 Meters

Ready to connect your Modbus meters?

Get started in 24 hours: order your Eziwan Gateway, connect your SDM630 devices, and view your data in real time. Technical support included.

🇫🇷 Hosted in France⚡ Up and running in 24 hours📞 Technical support included