I found some links related to your question:
1. CATHODIC PROTECTION, P E FRANCIS, http://www.npl.co.uk/upload/pdf/cathodic_protection_in_practise.pdf
2. Process of Cathodic Protection, Courtesy of CP Design Center by MESA Products, Inc., http://www.cpdesigncenter.com/public/technical/cp_process.htm
3. Patent application title: Process for Cathodic Protection of Electrode Materials,
Read more: http://www.faqs.org/patents/app/20080283417