Highlights The metallic neutral grounding resistors are designed for specific resistance values and voltages especially for shorter time ratings. The metallic neutral grounding resistors have the following advantages over a liquid type: Their resistance value is precise and determined at the manufacturing stage remaining constant throughout their life Their temperature time constant is shorter allowing a resistor of shorter time rating to be used. They are easier to install on site They require virtually no maintenance and have a longer useful life. No anti frost heating is required nor anti condensation heaters generally. Because of problem resulting from the evaporation of gel and electrolyte the liquid resistor constant maintenance Invariably the type of cooling will be natural air cooling.