Product Overview

The Siemens 6NH9720-3AA00 is a specialized SINAUT MD720-3 mobile radio modem designed to provide robust wireless data transmission for decentralized automation systems. This GSM/GPRS gateway enables PLC systems to communicate across cellular networks, making it a critical component for remote telemetry and telecontrol stations. By supporting quad-band frequencies, the 6NH9720-3AA00 ensures global compatibility for industrial data exchange via GPRS (packet-switched), CSD (circuit-switched), and SMS messaging. It acts as a transparent or AT-command-driven interface, allowing local controllers to transmit process data to central control centers or receive remote commands without the need for physical cabling infrastructure.

Hardware Communication Architecture and Physical Profile

The following hardware parameters define the 6NH9720-3AA00 technical capabilities:

• Wireless Standards: GSM Quadband (850/900/1800/1900 MHz)

• Data Services: GPRS Multislot Class 10, CSD (up to 9600 bit/s), and SMS

• Local Interface: 9-pin Sub-D (RS-232) supporting AT commands and PPI/MPI tunneling

• Antenna Connection: SMA female socket (50 Ohm)

• Supply Voltage: 24V DC nominal (Permissible range 12V to 30V DC)

• Energy Consumption: Approximately 5W during active transmission

• Diagnostic Indicators: LED array for signal strength, connection status, and power

• Ingress Protection: IP40

• Environmental Range: -20°C to +60°C operational temperature

• Net Weight: 0.95 kg

• Device Dimensions: 2.5 cm x 5.1 cm x 83.8 cm

• Manufacturing Origin: Germany

• HS Export Code: 8537101190

The unit is supplied with a gender changer for seamless integration with RS-232/PPI adapters, simplifying the link between the modem and SIMATIC S7 controllers.

Industrial Connectivity and Remote Telemetry Usage

The 6NH9720-3AA00 GPRS modem is specifically engineered for geographically dispersed automation projects where traditional Ethernet or fiber-optic connections are economically unfeasible. In the water and wastewater industry, it is widely utilized for monitoring remote pumping stations and tank levels, transmitting alarm states via SMS or GPRS to a central SCADA system. It is equally vital in the energy sector for the remote monitoring of substations and renewable energy installations, such as wind turbines or solar arrays located in rural areas. Its ability to maintain persistent GPRS connections makes it ideal for permanent data logging and remote maintenance of PLC-controlled machinery. By utilizing the SINAUT ST7 or Micro-Automation protocols, the MD720-3 provides a secure and reliable pathway for critical infrastructure data, ensuring that maintenance teams can receive real-time updates and perform remote diagnostics across the cellular network.