MERLIN Transformer Rectifier Monitor
The operation of transformer rectifiers (electrical units that place a voltage onto the pipeline to counteract the electrolytic corrosion reaction) is critical to cathodic protection. The voltage must be applied consistently and at the correct level: • Too low - and the pipeline will be insufficiently protected • Too high - and the pipeline may become brittle Pipeline operators are recommended to check the correct functioning of their rectifiers at monthly intervals. To be allowed to carry out functional rectifier checks, CP technicians must be trained on different electrical systems (AC supply and DC output). Many rectifier sites are remote and difficult to access. Rectifier measurements are taken automatically by a MERLIN Transformer Rectifier Monitor installed at the rectifier. This checks that the electrical supply is still present, monitors the voltage and current output and (optionally) can take ON and OFF potential measurements at the rectifier drain point. • MERLIN Transformer Rectifier Monitors are a range of small, compact units offering different measurement specifications. This monitor is usually housed within the rectifier cabinet. It communicates using the GSM network and can be supplied with either internal or external antenna, depending on the material of the rectifier enclosure. • The MERLIN XT Transformer Rectifier Monitor is mounted externally to the rectifier. This model uses satellite communication, so it requires a view of the open sky. It has an internal antenna. Regardless of the type of rectifier monitor or communication, all data is automatically transmitted in a management report to the system HQ where it is displayed and archived in Abriox's MERLIN CPSM3 software or online via iCPSM. Because they report to a common software platform, different rectifier types can be mixed together in the same monitoring network.