Once a cathodic protection system has been installed, it is crucial to test the system for proper operation. Once rust occurs, it cannot be undone. This test can be achieved using reference electrodes.

Reference electrodes are electrodes used in cathodic protection systems to measure the electrical potential of the protected metal structure. Said electrodes serve as a reference point for the potential differences between the protected structure and the environment.

Protection of a cathodic protection system

After a cathodic protection system is installed, an object must be effectively protected. The negative voltage of the protected object can be measured relative to a Cu/CuSO4 (copper sulphate), Ag/AgCl (silver chloride), or Zn/ZnSO4 (zinc sulphate) reference electrode.

The reference electrodes are used to measure the potential differences between the protected structure and the environment. These potential measurements help apply the correct amount of current to counteract corrosion.

Buying reference electrodes

At Merrem & la Porte, we have various types of reference electrodes available. For instance, we offer reference electrodes from M.C. Miller. These copper-copper sulphate reference electrodes are made of durable plastics. Additionally, we have reference electrodes from STELTH, known for their stable redox potential and suitability for measuring electrochemical potential in different conditions:

• Stelth 1: Suitable for water, soil, or underwater conditions. It has a small round ceramic tip that fully contacts the environment when there is a lot of water present.
• Stelth 2: Suitable for buried or concrete conditions. It has a ceramic moisture-retaining membrane that prevents the electrolytes from drying out or becoming contaminated.
• Stelth 3: Suitable for underwater conditions. It has a large ceramic tip resistant to high pressure and flow.
• Stelth 4: Suitable for concrete conditions. It has a flat ceramic tip that can be easily embedded in concrete.
• Stelth 8: Suitable for underground pipes or tanks. It has a cylindrical ceramic tip that can be placed in a pipe.
• Stelth 9: Suitable for underground pipes or tanks. It has a conical ceramic tip that can be placed in a pipe.

For more details about specific reference electrodes and how they integrate into your cathodic protection system, our team of specialists is ready to assist you.

Part number	Description
M.C. Miller
120407000	CuCuSO4 RE-5C with conical shaped surface (15210)
120407100	RE-5C plug assembly (15505)
120407001	CuCuSO RE-5 with flat surface (15108)
120407102	RE-5 plug assembly (15403)
Stelth 1 & Stelth 2
120403020	CuCuSO4 (SRE-002-SFY)
120403021	AgAgCl (SRE-004-SFB)
120403022	ZnZnSO4 (SRE-006-ZFR)
120403023	CuCuS04 (SRE-007-CUY)
120403024	AgAgCl (SRE-008-SUB)
120403025	ZnZnSO4 (SRE-009-ZUR)
Stelth 3
120403027	CuCuSO4 (SRE-010-CPY)
120403029	AgAgCl (SRE-011-SPB)
120403031	ZnZnSO4 (SRE-012-ZPR)
Stelth 4
120403040	CuCuSO4 (SRE-013-CPY)
120403041	AgAgCl (SRE-014-SPB)
120403042	ZnZnSO4 (SRE-015-ZPR)
120403070	CuCuSO4 (SRE-022-CIY)
Stelth 8
120403080	CuCuSO4 (SRE-034-CTY)
120403081	AgAgCl (SRE-035-STB)
Stelth 9
120403090	CuCuSO4 (SRE-037-CSY)
120403091	AgAgCl (SRE-038-SSB)
120403092	ZnZnSO4 (SRE-039-ZSR)

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