Wireless Modbus Interface

Connect Modbus RTU devices to your wireless IoT network without running RS-485 cables. Read registers from energy meters, PLCs, VFDs, and any Modbus-compatible industrial equipment over ZigBee mesh.

Modbus Master

RS-485 Modbus RTU Master

The ZMB acts as a Modbus RTU master on its built-in RS-485 port, polling connected slave devices for register data at configurable intervals. It supports all standard Modbus function codes for reading holding registers, input registers, coils, and discrete inputs. The RS-485 interface is isolated and features automatic bus direction control, ensuring reliable communication even on long cable runs and in electrically noisy industrial environments.

EpiSensor ZMB Modbus RTU master interface
Multi-Device

Connect Multiple Devices on One Bus

A single ZMB can communicate with multiple Modbus slave devices connected to the same RS-485 bus. Each device is addressed by its Modbus slave ID, and the ZMB polls each device in sequence according to its configured register map. This allows you to read data from several energy meters, variable frequency drives, or other Modbus devices in the same electrical panel using a single wireless interface, reducing hardware costs and simplifying deployment.

EpiSensor ZMB multi-device RS-485 bus
Flexible Configuration

Customisable Register Maps

The ZMB supports fully customisable register maps, allowing you to specify exactly which registers to read from each connected device. Configure register addresses, data types (16-bit integer, 32-bit integer, 32-bit float, 64-bit double), byte order (big-endian or little-endian), and scaling factors through the EpiSensor gateway or Core platform. Pre-built templates for common Modbus devices simplify setup, while custom maps provide flexibility for any device.

EpiSensor ZMB register map configuration
Wireless Bridge

RS-485 to ZigBee Wireless Bridge

The ZMB bridges the gap between wired Modbus RTU devices and the wireless EpiSensor mesh network. Register data read from RS-485 devices is packetised and transmitted over ZigBee to the gateway, eliminating the need for long RS-485 cable runs back to a central monitoring point. This is especially valuable in retrofit installations and across multiple buildings where running wired Modbus networks would be prohibitively expensive.

EpiSensor ZMB RS-485 to ZigBee bridge
Technical Details

Specifications

Model ZMB-3X
Serial Interface RS-485, isolated, half-duplex
Protocol Modbus RTU master
Baud Rates 1200 to 115200 baud (configurable)
Slave Devices Up to 32 per RS-485 bus
Data Types 16/32/64-bit integer, 32-bit float, coils
Wireless ZigBee (IEEE 802.15.4), 2.4 GHz
Mounting DIN-rail (35mm)
Power Supply 85-265V AC (internal PSU)
Operating Temperature -20°C to +55°C
Certifications CE
Download Datasheet (PDF)
Applications

Use Cases

Energy Meter Integration

Read Modbus energy meters wirelessly for detailed power quality data, harmonics, and billing-grade consumption monitoring.

Industrial Equipment

Connect variable frequency drives, PLCs, and motor controllers to monitor operational parameters and energy efficiency.

BMS Integration

Bridge Modbus RTU devices to modern building management systems via the EpiSensor gateway's protocol conversion.

Related Products

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ZGW-10 Gateway

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The central hub that collects all Modbus data and delivers it to your platform.

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Ready to Connect Your Modbus Devices?

Talk to our team to learn how the ZMB can wirelessly integrate your Modbus RTU devices.