IN485UNI001I100 – Universal IR to Modbus RTU Interface for AC Integration

IN485UNI001I100 – Universal IR to Modbus RTU Gateway for HVAC Control. 

The IN485UNI001I100 is a versatile gateway designed to integrate air conditioners controlled via infrared (IR) into Modbus RTU (EIA-485) automation networks. This solution enables centralized control and monitoring of AC systems using IR remote commands, making it ideal for both residential and commercial building management systems (BMS).

The interface is compatible with most air conditioner brands featuring built-in IR receivers. Whether your HVAC unit is a wall-mounted split system, cassette-type, or compact ceiling unit, this interface can provide a reliable link to your Modbus network.

Equipped with four high-performance IR emitters and a single IR receiver, the IN485UNI001I100 ensures bidirectional communication with the AC unit. Two emitters face forward, and two are angled downward at 45°, ensuring a broad IR coverage area. The IR receiver listens for feedback from the handheld remote, allowing accurate status updates within your Modbus system.

Installation is extremely flexible: the device supports wall mounting, desktop placement, or positioning near the AC unit – in front, to the side, or underneath. Its compact form factor enables deployment even in space-constrained environments without compromising signal quality.

The device communicates as a Modbus RTU Slave and supports baud rates ranging from 2400 to 115200 bps, with options for both 8N2 and 8N1 transmission formats. Its registers conform to 16-bit unsigned Holding Register format in standard Modbus big endian notation, ensuring compatibility with a wide range of PLCs, SCADA systems, and industrial controllers.

An integrated 120 Ω termination resistor can be enabled via DIP-switch for bus stabilization. Additionally, the interface supports installation in networks using Modbus RTU EIA-485 Masters with built-in termination or fail-safe biasing features.

A unique auto-learn function allows the gateway to capture and store commands from the IR remote control of the AC unit. This functionality extends compatibility to virtually any IR-controlled air conditioner, including those not explicitly listed in predefined compatibility databases.

Each Modbus RTU network can accommodate up to 63 individual IN485UNI001I100 interfaces. This allows for scalable HVAC integration across multi-zone systems. The unit includes a mini USB port for optional configuration and is also used for powering the device. A global power adapter kit is provided, featuring plugs for EU, UK, USA, and AU regions.

Key Features:

• Integration of IR-controlled AC units into Modbus RTU EIA-485 networks
• Brand-independent support for infrared-enabled HVAC units
• Four IR emitters and one IR receiver ensure comprehensive signal exchange
• Wall, desktop, or flexible mounting near the air conditioner
• Auto-learn mode for capturing remote IR signals quickly and easily
• Modbus RTU Slave functionality with 8N1 and 8N2 protocol support
• Configurable baud rate: 2400 to 115200 bps
• Built-in 120 Ω resistor enabled via DIP-switch for network termination
• Mini USB port for optional setup and for power input
• Power adapter with interchangeable plugs (EU, UK, USA, AU)
• Simultaneous control from Modbus master and IR remote
• Compact dimensions and non-intrusive installation
• 36-month manufacturer's warranty

The IN485UNI001I100 is the ideal solution for retrofit HVAC projects, system expansions, or BMS integrations where standard air conditioning units need to be integrated into a centralized Modbus-based infrastructure. Reliable, scalable, and easy to configure, this gateway is a robust tool for system integrators and automation professionals.

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