Monitoring for Water and Sewage
Ensure efficiency with Water and Sewage Monitoring: advanced IoT solutions for real-time control, analysis, and management of sanitation.
Challenge
Remotely communicate PLCs spread across several units of the Water and Sewage system of a large Brazilian city.
Solution
Multiplexing of Serial PLCs over the Internet via a virtual Serial channel.
The client's requirement was to provide control and telemetry for several points in the water supply and sewage system of a large Brazilian city. The high cost of acquiring and maintaining dedicated lines (LPs) made it extremely costly to perform these tasks reliably and continuously. The Operational Control Center, located at the client's headquarters, required constant communication with the PLCs located at these points.
Project requirements:
- Reliable and stable communication with PLCs spread throughout the city, many in hard-to-reach areas;
- Affordable cost of the solution;
- Possibility of connection via Ethernet or Serial on the same equipment, for standardization and integration with different PLC models.
Various technologies were tested, and each demonstrated weaknesses, such as low robustness or communication instability. LPs, for example, frequently suffered from stolen wires. Wireless communication solutions were unviable due to visibility and distance issues. Satellite communication, in turn, had very high operating costs.
In addition to these challenges, there was another complicating factor: multiplexing serial networks for PLC communication over the cellular network. Among several competitors, Above-Net was the only one able to overcome this barrier and deliver a reliable, highly available, and cost-effective solution.
The solution consists of a 3G router connected to the PLC, which in turn connects to various devices at the stations. The router remains permanently connected to the Bridgemanager cellular connection management system and can inform the supervisor of the access path of each device connected to the PLC. This allows the customer to monitor multiple devices safely and reliably through a single cellular connection.