Polarization Probe: It consists of a copper-copper sulfate reference electrode and a carbon steel plate and a salt bridge around it. The steel plate is connected to the measured pipe through a wire and a test pile and is polarized. So that the resistance of the measurement channel to minimize the voltage drop and effectively shield the external current interference, making the stray interference area is very difficult to measure the potential of the tube becomes simple, smooth, reliable and true. Compared with similar products in foreign countries, it has the advantages of novel structure, good stability, strong and reliable, long service life, easy to carry and application in engineering site and to use CSE (copper / copper sulfate reference electrode) commonly used in China's soil cathodic protection project. To measure and mark the reference potential (imported polarized probe commonly used SCE), which is more suitable for our country's new generation of reference electrode.