Abstract
Impressed current cathodic protection (CP) systems for water storage tanks must be periodically tested in order to ensure proper performance. Remote monitoring units (RMU) provide the ability to monitor CP system performance data from remote locations using modem-equipped personal computers. They can provide their data to a central location through an existing supervisory control and data acquisition (SCADA) systems or through other wireless monitoring systems. Application case histories at several military installations, including criteria for upgrading existing CP systems and selection and implementation of appropriate RMUs, will be discussed.
Military Installation #1 is a very large installation with 8 potable water storage tanks and many miles of piping that use ceramic-coated anode cathodic protection systems. Two RMUs were recently implemented, one on a 2 million gallon water storage tank, and the other on a 1.5 million gallon tank. The units provide capabilities to remotely monitor the cathodic protection system’s current and “instant-on” and “instant off potentials,” which are displayed at the Utility Control System Administrator’s office. The RMUs have allowed continuous monitoring of CP systems from a central location, and provide personnel with immediate warning of potential corrosion hazards. These units are available as commercial off-the-shelf technologies in the $500 to $1000 price range. Based on the success of these units, RMU technology is being implemented for similar potable water tanks and underground pipes at additional Military Installations.
The benefits of implementation of the RMUs are the cost avoidance of traveling to remote sites to check each rectifier, and the added capability of instant notification of a malfunction in the cathodic protection system, thus increasing the life of the structures being protected.
