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DRM - I/O module with relay outputs and Modbus RTU

An I/O module with relay outputs is a device commonly used in industrial and automation applications to interface between a control system (such as a programmable logic controller or PLC) and external devices or equipment.
DRM - I/O module with relay outputs and Modbus RTU
An I/O module with relay outputs and Modbus RTU functionality combines two key features: digital output control through relay outputs and communication using the Modbus RTU protocol.

Some of the functionalities provided by such a module are:
Relay Outputs: The module includes one or more relay outputs, typically used for switching external devices on or off. Relay outputs are the primary feature of these modules. They are electromagnetic switches that can open or close electrical circuits in response to a control signal. Each relay output typically consists of a relay switch and associated terminals for connecting external devices.                                                                                                 
Switching Loads: The relay outputs can control various types of loads, such as motors, valves, lights, pumps, and other industrial equipment that require on/off control.
Isolation: To protect the connected devices and the control system, the relay outputs often provide electrical isolation, preventing electrical noise or voltage spikes from affecting the control circuitry.
Configurability: Users can configure the relay outputs to control devices based on specific conditions or logic, such as latching, time delays, or other control sequences.
Form Factor: I/O modules can come in different form factors, such as DIN rail-mounted or panel-mounted modules, to suit the installation requirements of the application.
Modbus RTU Protocol: Modbus RTU is a widely used communication protocol in industrial automation and control systems. It's a serial communication protocol that allows for the exchange of data between devices over a serial connection, such as RS-232 or RS-485. The I/O module supports the Modbus RTU protocol for communicating with other Modbus-compatible devices, such as PLCs, HMI (Human-Machine Interface) systems, or SCADA (Supervisory Control and Data Acquisition) systems. This enables the controller to monitor and control the relay outputs and exchange data with other devices connected to the module.

With Modbus RTU, the module can perform read and write operations to exchange data with other devices. For example, it can read data from sensors or write control commands to other Modbus devices.
Modbus RTU devices have unique addresses, allowing them to be individually addressed and accessed on the Modbus network. The module can be configured with a specific Modbus address for proper communication.
The module facilitates automation and control by allowing the controller to remotely activate or deactivate relay outputs, which, in turn, control external devices or processes.
In summary, an I/O module with relay outputs and Modbus RTU functionality combines the capabilities of digital output control through relay switches with the ability to communicate with other devices using the Modbus RTU protocol. This combination is valuable in industrial automation and control applications where remote control of external devices and data exchange with other devices or systems is required.


To satisfy all of the aforementioned requirements, Sentera created an I/O module with relay outputs and Modbus communication. There are two versions of it: DRM-M-02 with two relay outputs and DRM-M-04 with four.
These Modbus RTU (RS485)-operated DIN-rail modules transfer the data provided by Modbus commands to cause the C/O relay contact to change.
Our online HVAC portal SenteraWeb as well as the 3SModbus application allow users to view and modify measurement values and parameter settings.
With the embedded bootloader, firmware updates can be pushed using the 3SModBus app or SenteraWeb.

Visit our website to view the other I/O modules we offer.
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