---
title: "GWU-2 2G GSM/GPRS gateway for Modbus RTU devices | GridBit"
description: "GWU-2 is a DIN-rail communication module. It reads the devices on an RS485 Modbus RTU bus and sends their data to the EIM center over GSM (GPRS), and it can."
url: "https://www.gridbit.tech/hardware/gwu-2"
language: "en"
translation: "https://www.gridbit.tech/bg/hardware/gwu-2"
---

# GWU-2

2G GSM/GPRS gateway for Modbus RTU devices

[Request a quote](https://www.gridbit.tech/contact?product=GWU-2)

- **Mobile network**: 2G GSM/GPRS
- **Modbus RTU**: RS485
- **Digital inputs**: 2
- **Supply voltage**: 9 to 36 VDC

Overview

## Where it works

GWU-2 is a DIN-rail communication module. It reads the devices on an RS485 Modbus RTU bus and sends their data to the EIM center over GSM (GPRS), and it can also write parameters received from the EIM center into the Modbus registers of the connected devices. It has two digital inputs for tampers, switches and similar contacts, and runs on 9 to 36 VDC.

Mounting: 35 mm DIN rail (IEC 60715)

1. Integration with the GridBit energy monitoring and management system (EIM)
2. Data retrieval, remote configuration and control of the devices on the Modbus bus over GSM 2G
3. Monitoring the state of the two digital inputs, for tampers, switches and similar contacts

GWU-2 gateway, three-quarter view

Datasheet

## Technical data

### Power supply

- **Supply voltage**: 9 to 36 VDC
- **Consumption**: max. 50 mA

### Digital inputs

- **Number**: 2
- **Type**: IEC 61131-2 Type 1

### Modbus RTU

- **Interface**: RS485
- **Protocol**: Modbus RTU
- **Baud rate**: 9600, 19200, 38400, 57600 default 9600
- **Parity**: 8N1, 8E1, 8O1, 8N2 default 8N1

### Mobile network

- **Standard**: 2G GSM/GPRS
- **Frequency bands**: GSM 850 MHz, EGSM 900 MHz, DCS 1800 MHz, PCS 1900 MHz

### Environment

- **Operating temperature**: -20 to 60 °C
- **Storage temperature**: -20 to 80 °C
- **Relative humidity**: below 95 %, non-condensing

### Status LEDs

- POW On Input voltage present
- COM Blinking Connecting to the GSM operator
- COM On Connected to the EIM center
- Di1 On Digital input 1 closed
- Di2 On Digital input 2 closed

Installation

## Dimensions and connection

Dimensions in mm

Connection diagram

On a 35 mm DIN rail

Systems

## Used in

EIM

### [Electrical infrastructure monitoring](https://www.gridbit.tech/solutions/eim)

Sensors, analysers and a gateway turn a secondary substation into a monitored asset. The platform shows the transformer and the low-voltage board in real time, with alarms and reports for the grid operator.

Learn more

[Previous GWU-4 2G/4G gateway for Modbus RTU devices, two digital inputs](https://www.gridbit.tech/hardware/gwu-4)
[Next MCU-4 Three-phase network analyser with Modbus RTU](https://www.gridbit.tech/hardware/mcu-4)

### Transport, warranty and maintenance

- **Transport and storage**: Protect the module from shocks and avoid extreme conditions. Store it in the original packaging.
- **Warranty**: Two years from the date of manufacture against manufacturing defects. Modifications to the product after the publication date of its documentation release the manufacturer from liability. The manufacturer is not responsible for typographical or other errors in the documentation.
- **Maintenance**: Under normal conditions the module needs no maintenance. Light dirt comes off with a dry or slightly damp cloth; for heavier dirt use non-aggressive cleaning products. Always disconnect the power supply first, keep liquids out of the housing and reconnect the power only when the module is completely dry.

## Ask for a GWU-2 quote

Tell us the quantity and the project. We answer with a price and lead time.

[Request a quote](https://www.gridbit.tech/contact?product=GWU-2) [office@add-bg.com](mailto:office@add-bg.com)