Source google image: https://www.researchgate.net/profile/Mourad_Haddadi/publication/228653992/figure/fig3/AS:302065990553605@1449029552427/Schema-du-circuit-electrique-du-systeme-de-regulation-de-la-protection-cathodique-par.png
Schema electrique biphase
Source google image: https://www.researchgate.net/profile/Mourad_Haddadi/publication/228653992/figure/fig3/AS:302065990553605@1449029552427/Schema-du-circuit-electrique-du-systeme-de-regulation-de-la-protection-cathodique-par.png