HM Series I/O Expansion Module

HM series I/O module is used to expand the I/O points of Hailin HD and D series DDC controller. This series has multiple models, can be adapted to input and output points of different signal types according to the requirements of the project site, and can be economically combined into a complete and independent local control system. It has RS485 communication port, supports

ModBus RTU and BACnet MS/TP protocols, it is also a standard I/O module that can be connected the third party’s system.

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The HM Series I/O Expansion Module is a flexible I/O module designed to expand the I/O points of Hailin HD and D Series DDC controllers. With multiple models and different combinations of universal inputs, digital inputs, digital outputs, and voltage outputs, the series can be configured according to the I/O requirements of different building automation projects.

Featuring an isolated RS-485 interface, the HM Series supports Modbus RTU and BACnet MS/TP communication protocols, allowing it to operate as a distributed field I/O device within DDC, BAS, BMS, and HVAC control systems.

The HM Series can be combined with Hailin DDC controllers to build flexible local control systems. It can also be integrated with compatible third-party building automation systems through supported communication protocols, making it suitable for both new projects and building automation retrofit applications.

Key Features of HM Series I/O Module

Flexible I/O Expansion for DDC Controllers

The HM Series is designed as a DDC I/O expansion module for Hailin HD and D Series controllers.

Different models provide different combinations of UI, DI, DO, and VO points, allowing project designers to select an appropriate I/O configuration according to the number and type of connected field devices.

This modular architecture helps expand controller capacity without requiring a single controller with a fixed I/O configuration.

Multiple I/O Configurations

The HM Series includes models with different I/O combinations, including:

Universal Inputs (UI)
Digital Inputs (DI)
Digital Outputs (DO)
Voltage Outputs (VO)

With models ranging from 4 to 19 total I/O points, the series can accommodate different control and monitoring requirements.

BACnet MS/TP and Modbus RTU

The HM Series supports two widely used building automation communication protocols:

BACnet MS/TP

Modbus RTU

This enables the BACnet I/O module or Modbus I/O module to communicate with compatible DDC controllers, BMS/BAS platforms, and third-party automation systems.

Isolated RS-485 Communication

Each HM Series module provides one isolated RS-485 communication interface with baud rates from 9600 to 115200 bps.

The isolated interface helps support reliable communication in distributed building automation networks.

Third-Party System Integration

The HM Series is a standard I/O module that can be connected to compatible third-party building automation systems through supported BACnet MS/TP and Modbus RTU protocols.

This provides flexibility when integrating field I/O into existing or mixed-vendor control architectures.

Selectable RS-485 Termination Resistor

The module includes a selectable RS-485 termination resistor, which can be enabled using the built-in button.

This can simplify RS-485 network installation by reducing the need for an external termination resistor at the appropriate end of the communication bus.

Flexible Installation

The HM Series supports installation using screws on a flat surface or a 35 mm DIN rail mount, providing flexibility for control cabinets and distributed field installations.

Compact and Flame-Retardant Housing

The modules use a PC+ABS flame-retardant material and have an IP20 protection rating, making them suitable for indoor control panels and protected building automation installations.
Specifications

MModel		HM0008	HM0004	HM1405	HM0800	HM0704
Electrical characteristic	Power Supply	AC/DC24V±10%，50-60 Hz
	Operating temp. & humidity	0~50℃（32~122℉）；10~90% relative humidity, non-condensing
	Storing temp. & humidity	-40~70℃（-140~158℉）；10~90% relative humidity, non-condensing
Communication	RS-485	One RS-485 interface（1500Vrms isolated）
		Baud rate：9600~115200（unit：bps default：9600bps）
		Equipped with termination resistor：termination resistor selectable（enabled by button）
		Data bit: 8; Stop bit: 1; Check: No check, even check, odd check (default: no check)
		Protocol：Modbus RTU、BACnet MS/TP
		Mode：Modbus sub-mode
W x L x H (mm)		120x149x58	120x149x58	180x149x58	120x149x58	120x149x58
Installation		Screws are positioned on a flat or 35mm DIN rail mount
Material		PC+ABS flame retardant
IP rating		IP20

Models

Model	UI	DI	DO	VO	Total points	RS-485 interface	Reset button	EOL button (485 terminal resistance)	Support protocol
HM0008			8		8	1	√	√	BACnet/ModBus
HM0004				4	4	1	√	√	BACnet/ModBus
HM1405		14	5		19	1	√	√	BACnet/ModBus
HM0800	8				8	1	√	√	BACnet/ModBus
HM0704	4	3	2	2	11	1	√	√	BACnet/ModBus

Applications of HM Series I/O Module

DDC Controller I/O Expansion

The primary application of the HM Series is to expand the I/O points of DDC controllers.

When a building control project requires more field points than are available on the main DDC controller, HM Series modules can be connected through RS-485 to provide additional I/O capacity.

HVAC Control

The HM Series can be used as a field I/O module in HVAC control systems, supporting monitoring and control of compatible sensors, equipment status signals, actuators, valves, dampers, fans, pumps, and other HVAC field devices.

When connected to a DDC controller, the module can become part of a distributed HVAC control architecture.

Building Automation Systems

The HM Series can be deployed as a building automation I/O module within BAS and BMS systems.

Its BACnet MS/TP and Modbus RTU communication capabilities allow field I/O information to be exchanged with compatible building automation controllers and supervisory systems.

Distributed Building Control

For buildings with distributed equipment and control points, multiple HM Series modules can be installed close to field devices and connected through RS-485 communication networks.

This distributed architecture can help reduce wiring distance between the controller and field equipment.

Third-Party Building Automation Integration

The HM Series can be integrated into compatible third-party BAS/BMS systems using BACnet MS/TP or Modbus RTU.

This makes the module suitable for projects where additional field I/O needs to be integrated into an existing automation architecture.

Building Automation Retrofit

The HM Series can be used in selected building automation retrofit projects where additional I/O capacity or protocol-compatible field interfaces are required.

Its RS-485 communication and support for BACnet MS/TP and Modbus RTU provide options for integrating the module into existing control networks.

New Building Projects

For new commercial and institutional building projects, HM Series modules can be combined with DDC controllers to create scalable and distributed building automation control systems.

Why Choose HM Series I/O Expansion Modules?

Scalable I/O Capacity

Multiple module configurations allow users to select the number and type of I/O points required for a project.

Flexible System Architecture

HM Series modules can expand Hailin DDC controllers and can also be used in compatible third-party systems.

Standard Building Automation Protocols

Support for BACnet MS/TP and Modbus RTU facilitates integration with widely used building automation networks.

Distributed Installation

RS-485 communication and DIN rail installation support make the modules suitable for distributed control panels and field installations.

Suitable for New and Retrofit Projects

The modular design can be applied to both new building automation systems and selected retrofit projects requiring additional I/O capacity.

Frequently Asked Questions

What is an I/O module?

An I/O module is a device used to provide input and output points for a control system. It allows a controller or automation system to monitor field signals and send control signals to connected equipment.

What is the HM Series I/O module used for?

The HM Series I/O module is primarily used to expand the I/O points of Hailin HD and D Series DDC controllers. It can also be integrated into compatible third-party building automation systems.

Can the HM Series expand a DDC controller?

Yes. The HM Series is specifically designed as an I/O expansion module for Hailin HD and D Series DDC controllers.

Does the HM Series support BACnet?

Yes. The HM Series supports BACnet MS/TP communication through its RS-485 interface.

APPLICATION

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HM Series I/O Expansion Module

description

Key Features of HM Series I/O Module