SMS-GW3: a gateway for sending SMS messages from HWg devices

HWg-SMS-GW3 is a central text message (SMS) gateway that HWg devices and applications in the same network can use to dial numbers or send SMS alerts. Target phone numbers are specified in the sending device or the HWg-Trigger application.


The central HWg-SMS-GW3 text message gateway significantly saves costs of external GSM modems as the entire installation only needs one SIM card. Neither additional software nor internet connectivity are needed.

  • Ethernet: 10/100 Mbit/s
  • Configuration: WEB interface
  • GSM antenna: External 3m cable, SMA
  • GSM standard: Quad-Band 850 / 900 / 1800 / 1900 MHz
  • Can be used to send SMS from: Poseidon2, HWg-WLD, HWg-PWR 3 / 12 / 25, IP WatchDog2, Poseidon 2250
  • Can be used to send SMS from the following software and services: HWg-Trigger software, HWg-DCD software, Nagios monitoring software (Netways:, online service
  • M2M communication protocols: SNMP, XML, netGSM (http, SOAP)
  • Internal memory for outgoing SMS queue: 100 messages
  • Support for programmers: HWg-SDK
  • Mechanical: 76 x 93 x 28 mm, wall-mountable, fits on a DIN rail
Applications and usage: 


  • One SMS gateway for the entire network with web-based configuration.
  • No additional software needed in order to send text messages.
  • SMS recipient's phone number is configured in the sending device.
  • Supports an “SMS + Ring” function.
  • Connection for an external antenna.
  • Quad-Band GSM.
  • Examples for programmers available in the HWg-SDK (Borland C++, MS Visual C, VB, C#, PHP, JAVA and more).

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Sending SMS alerts from Poseidon units over the LAN                                               Sending SMS alerts from Poseidon units over the LAN                                                

  • Poseidon2 4002 sends an alarm message about a sensor value to Mr. Blue's phone number.                                                                                                                                                                                           
  • Using the Box-2-Box mode, it connects directly to the HWg GSM gateway (no software is needed).                                                                  
  • HWg-SMS-GW contains a SIM card and sends cell message alerts on behalf of all devices in the network.       
  • Message recipients' phone numbers (Mr. Blue, Mr. Green, ...) are configured in the sending device.
  • Together with the text message, it is also possible to call the recipient and let the phone ring for a short time (configured in the sending device).       

HWg-Trigger: Monitoring software with SMS alarms over SMS GW3                                                                                                                                                                                      HWg-Trigger: Monitoring software with SMS alarms over SMS GW3

  • HWg-Trigger, an application for MS Windows, monitors the function of other products (Poseidon2 3266, HWg-STE Push, Damocles 1208, Poseidon 4002) over the LAN.                                                            
  • If a product is inaccessible or fails, a SMS alert is sent using HWg-SMS-GW3 in the same LAN.
  • Recipients' phone numbers (Mr. Purple, Mr. Green) are configured in HWg-Trigger.
  • HWg-SMS-GW contains a SIM card and sends text message alarms to different phone numbers.

Alerts to events: HWg-Trigger

HWg-Trigger software allows reacting to events. For instance, “If the device at the address X does not work, do Y”. The software runs on Windows in the background and keeps checking the configured conditions.

  • Monitors IP sensors in the LAN: sends a SMS if a sensor is disconnected
  • Monitors IP sensors in the LAN: sends a SMS in case of device failure
  • Monitors IP sensors in the LAN: sends a SMS in case of sensor value out of Safe Range
  • 30-day trial version is free of charge
  • Runs in the background as a Windows service (NT service)


>> HWg-Trigger software


Nagios SMS alerts

  • Nagios NMS monitors other devices using SNMP.                                             Nagios SMS alerts
  • In the Nagios system, a plugin enables SMS alerts over HWg-SMS-GW gateway.
  • The plugin configuration includes the phone numbers of text message alert recipients.
  • For details about obtaining and using the Nagios plugin, see the product manual.
  • The plugin was created in cooperation with Netways (MonitoringExchange:

>> Nagios (Third-party monitoring software) 

SMS alerts from the online portal

  • LAN and GSM sensors (HWg-STE Push and Ares 12) send data to the online portal.
  • Your user account includes the IP address or DNS name of your HWg-SMS-GW (must be accessible at a public IP address).                                                                                                                                               
  • The configuration of each sensor in your SensDesk account can include a phone number for alarm messages.  SMS alerts from the online portal
  • Note:
    Ares 12 sends the alert to an out-of-range sensor value faster than the SensDesk portal; however, SensDesk allows to monitor and configure all alarms over the Web at a single place.
     In addition, SensDesk also monitors the network connectivity of Ares units, so it can for instance alert to an Ares unit's network connection failure.