Sulfur Inhibitor Fluid

Sulfur Inhibitor

DSI Sulfur Inhibitor is a pre-mixed, liquid concentrate blend of advanced Metal Passivators, Oxidation Inhibitors and Sulfur Stabilizers that stops corrosive sulfur in its tracks. It is applied to transformers where there is corrosive sulfur or low oxidation inhibitor content.

Because Sulfur Inhibitor is a liquid, it is simply added to a de-energized transformer. No further mixing or blending is required. DSI Sulfur Inhibitor is dried, degassed, and highly processed. It is compatible with all brands of standard mineral oil, as well as Beta fluid, R-Temp fluid, Alpha-1 Fluid, and vegetable oil dielectrics.

Why is DSI Sulfur Inhibitor a Better Solution?

Corrosive Sulfur is often treated with tolyl-triazole or benzo-triazole compounds. These compounds are called “yellow metal passivators” because they form a coating on metals that contain copper. But this only solves part of the problem!

Corrosive sulfur will combine with iron and aluminum, too, and cause similar problems as with copper. A Yellow Metal Passivator does nothing to prevent these reactions. Also, different types of copper in your transformer will react differently with the different types of passivators. If you’re only using one, then you’re not fully protected.

DSI Sulfur Inhibitor stops corrosive sulfur with a three-way attack. It contains a mixture of copper passivators, not just one. This ensures that all types of copper will be protected. DSI Sulfur Inhibitor also contains a blend of several powerful antioxidants. This protects the oil and paper in your transformer from further oxidation, and inhibits their ability to enter into chemical reactions. Third, DSI Sulfur Inhibitor contains proprietary compounds that “stabilize” the sulfur in transformer oil. This will make the sulfur less aggressive and lower its corrosive qualities.

Taken together, these three actions have far more inhibiting and preventive effect than a yellow-metal passivator alone. This is why we say that DSI Sulfur Inhibitor stops corrosive sulfur in its tracks.


Sulfur Inhibitor is added to transformer oil to prevent corrosion, plating, or other problems caused by corrosive sulfur. Five gallons of DSI Sulfur Inhibitor will treat 200 gallons of transformer oil.

Processing and Handling:

DSI Sulfur Inhibitor is available in 5 and 55 gallon containers.

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