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Installing wireless modems allows a Puerto Rico water authority to monitor the water pool's moving bridges efficiently from a central location.
By Roberto Acosta, Engineer, Accurate Solutions & Design, and Sam Amaral, Electronic Systems Technology, Inc.
At a water treatment plant in Mayaguez, Puerto Rico, the Authority of Aqueducts and Sewage Systems implemented a state-of-the-art SCADA system to communicate with the otherwise remote locations.
At each remote location, an ESTeem 192S is connected to an Allen-Bradley MicroLogix 1000 processor. The data from each remote node is transmitted wirelessly by the 192S to a control room computer, via another 192S.
When confronted with the challenge of monitoring two continuously traveling bridges at a Mayaguez, Puerto Rico water treatment plant, the Authority of Aqueducts and Sewage Systems implemented a state-of-the-art SCADA system to communicate with the otherwise remote locations. The bridges operate over wastewater pools, continuously moving in both directions of the pool to agitate the contents. Communicating using a traditional hardwired network wasn’t a viable option because of the continuous movement.
With this type of critical information being monitored, a dependable and reliable network structure is vital. Prior to installing their system, water treatment plant personnel teamed with Accurate Solutions & Design engineers to thoroughly investigate all the options available on the market. They needed hardware capable of meeting today’s demands with the flexibility to meet future needs. After considering all the options, the water authority chose to implement a SCADA system using wireless modems from ESTeem, a participating Encompass™ Product Partner in the Rockwell Automation PartnerNetwork™.
ESTeem worked with Accurate Solutions & Design engineers to design a tailor-fit wireless network. A radio analysis of the site found that three ESTeem radio sites could establish reliable communications and provide full coverage for a common network.
The ESTeem 192S spread spectrum modem was chosen because of its affordability, secure encrypted transmissions and a 171K-bps data rate while maintaining a data accuracy of greater than one part in 100 million. The wireless modems can operate as a master, remote or repeater node, so they provide a cost advantage compared to conventional systems.
At each remote location, a 192S is connected to an Allen-Bradley® MicroLogix™ 1000 processor (www.rockwellautomation.com/go/tjmicrologix1000) from Rockwell Automation. The data from each remote node is then wirelessly transmitted by the 192S to a control room computer, via another 192S.
Using Rockwell Software RSLinx® (www.rockwellautomation.com/go/tjrslinx), the computer in the control center polls each one of the bridges for the desired information, which is displayed in the site’s SCADA screens.
Using the 192S has allowed the Authority of Aqueducts and Sewage Systems in Mayaguez, Puerto Rico to monitor and control the entire SCADA system, including the two bridges, from a central point. This has increased personnel efficiency and monitoring reliability for the water treatment plant.
Note: The ESTeem 192S has been updated in current inventory with the ESTeem 195E models. They provide the same features and include an increase in RF data rate to 200K bps. They both have an Ethernet and serial port.
For more information about ESTeem Wireless Modems narrow-band licensed, spread spectrum licensed and unlicensed Ethernet/Serial radio modems for long-range outdoor and indoor applications, visit www.rockwellautomation.com/go/p-est.
