4Z Elektronik is proud to win the Materials Performance Magazine (AMPP) “Corrosion Innovation of the Year Award” for its revolutionary SMC10 Smart Mitigation Cell – an innovative technology solution for stray currents caused by telluric effect, trams and subways in cathodic protection systems.
The Award was presented at AMPP CORROSION 2025 Conference and Expo which held in Nashville, Tennessee – USA. With approximately 60 nominations from companies across the world going forward to the judging panel of corrosion control experts, 4Z Elektronik is especially honoured to be the first Turkish company nominated for making a significant positive impact in corrosion control.
Innovation summary: Cathodic overvoltages caused by direct current (DC) stray currents, especially originating from subway and tram lines are well known all around the world.
They can be very difficult to mitigate by conventional methods. The general approach is to ground the structure over a DC decoupler or by using some sort of metallic (zinc, etc.) grounding. The former method presents an impedance and threshold voltage, which is device specific and changes with the type of grounding material used. The latter method may require too many grounding anodes to be buried, which causes non-uniform cathodic protection (CP) current distribution. This is costly and may not even be possible to apply, at all.
Our new approach utilizes any type of (safe) grounding for mitigation of DC stray current by using a variable resistance technique. The smart mitigation cell (SMC) incorporates a DC decoupler together with a reference electrode monitor and a controlled electronic variable resistor, whose resistance can be between 0.2 ohms to nearly open circuit. The SMC monitors the reference-to-structure potential and adjusts the DC current drain by changing the series resistance. In this way, the reference potential is always at the setpoint, and overvoltage is mitigated.
Related news from AMPP’s web site: https://showdaily.ampp.org/news/materials-performance-announces-2025-corrosion-innovation-of-the-year-awards