IoT Pro
RS485 Module
A retrofit industrial RS485 communication module designed to interface with Modbus and serial-based field devices, enabling structured data acquisition from legacy and industrial equipment, and built on the IoT Pro industrial hardware architecture.
Product Code: IOTPRO-RS485-MODULE
Product Overview
The IoT Pro RS485 Module is an industrial serial communication module designed to interface with RS485-based devices and expose their data to modern software platforms without replacing the original equipment.
Rather than monitoring raw electrical or physical signals, this module acts as a protocol-aware edge gateway, polling and decoding structured registers from field devices using standard serial communication methods.
From a system architecture perspective, the module functions as a serial data acquisition and protocol-bridging node, allowing software integrators to connect existing RS485 equipment into IoT systems with deterministic behaviour, long-term stability, and predictable data structures.
This module is particularly valuable where installed base equipment already provides rich data, but lacks connectivity, remote access, or modern integration interfaces.
Typical Installation Points
The IoT Pro RS485 Module is typically installed where RS485-based devices are already present, and replacing them would be costly, disruptive, or unnecessary. These deployments often involve multi-drop buses, long cable runs, and electrically noisy environments where RS485 is preferred over point-to-point signalling.
Electrical Panels
Modbus energy meters
HVAC Plants
VFDs / Chillers / Plant Controllers
Water Infrastructure
Pump Stations / RS485 Instrumentation
Industrial Equipment
Status & Counters via Modbus RTU
Environmental Sensors
Monitoring Equipment with Serial Outputs
Utility Cabinets
Multi-drop RS485 Networks
OEM Equipment
Exposed RS485 Service Ports
Interface Capabilities
The RS485 interface enables communication with a wide range of industrial devices using half-duplex, differential serial communication.
RS485-Capable Devices
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Energy meters and power quality analysers (Modbus RTU)
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Variable frequency drives (VFDs)
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PLC expansion modules and remote I/O blocks
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Flow, level, and pressure transmitters with Modbus output
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HVAC controllers and BMS field devices
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Weighing systems and industrial counters
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Battery management systems (BMS) and UPS equipment
The module is designed to operate reliably on shared RS485 buses, supporting polling-based data acquisition from one or multiple devices on the same line.
Channel Architecture
The IoT Pro RS485 Module combines advanced industrial serial communication with flexible auxiliary I/O, enabling integrators to interface with legacy and modern industrial equipment using structured protocols, while also capturing discrete signals and analog measurements in the same node.
Serial Interface (1 x RS485)
The core of this module is it's RS485 serial communication interface, designed for robust, electrically differential signalling suitable for industrial environments.
Unlike simple converters that simply bridge RS485 to a network, the IoT Pro RS485 Module implements a fully integrated serial data acquisition and processing engine, enabling:
Multi-device Polling with Configurable Addressing
Supports master mode to poll multiple devices on a shared RS485 bus.
Real-time Protocol Parsing
Interprets and extracts structured register data from connected devices rather than just transparently tunnelling raw bytes.
Configurable Serial Parameters
Support for a wide range of baud rates, parity, and stop bit configurations to match typical industrial settings.
Protocol Stack Modularity
Integrators can map industry standard protocols (e.g., Modbus RTU, DNP3 over RS485, custom ASCII/RTU protocols) into structured output for platforms.
Error Detection & Recovery
Handles CRC checks, bus contention, retries, and dead device timeouts to ensure reliable acquisition on noisy or long RS485 runs.
These capabilities go well beyond simple register reading (e.g., reading up to 16 or 32 registers as with basic controllers) and support application-level usability directly from the edge device.
Additional I/O Interfaces
This hybrid architecture allows protocol data and physical signals to be correlated within a single device.
Digital Inputs
4 x Configurable Inputs
Dry Contact Inputs
Pulse Inputs
Temperature Probes (DS18B20)
Suitable for monitoring contact-based signals and discrete events such as door status, limit switches, tamper contacts, auxiliary temperature points, and pulse outputs from counters or meters.
Analog Input
1 x 0-30 V Voltage Input
Suitable for monitoring external power sources, battery systems, or auxiliary equipment states.
Digital Output
1 x Digital Open-Drain Output
500 mA Continuous Current
Up to 1 A Pulse Capability
This hybrid architecture allows protocol data and physical signals to be correlated within a single device.
IoT Pro Hardware Architecture
Power-Intelligent Operation with Backup
Enables continued monitoring and recovery after power interruptions, which is critical when interfacing with field equipment that may reboot or change state during outages.
Flexible Connectivity, One Integration Model
Allows RS485 devices in deep plant rooms or remote cabinets to be integrated using 4G LTE Cat 1, NB-IoT, LoRaWAN, Wi-Fi, or hybrid network strategies without changing software integration.
Antenna & Mechanical Flexibility
External and through-lid antenna options enable reliable communication even when the module is installed inside metal panels or electrically shielded enclosures.
Modularity for Legacy Integration
Enables gradual modernisation of legacy infrastructure without replacing existing equipment or introducing external protocol conversion hardware. An optional integrated GNSS module supports applications involving mobile or relocatable assets.
System Integration Context
The IoT Pro RS485 Module is typically used as a protocol bridge within energy management, industrial monitoring, water infrastructure, and BMS-style deployments.
It enables organisations to extract significantly more value from existing RS485-enabled equipment by making data remotely accessible, analysable, and actionable.
Technical Documentation
All documentation is written for software integrators, system engineers, and deployment teams and aligns with the IoT Pro platform architecture.