Which type of modern distribution lightning arrestor has no gaps between valves?

The metal oxide arrestor, often made with zinc oxide, is recognized for its lack of gaps between the valves. This design allows for a more effective suppression of voltage transients, as it facilitates continuous conductivity during normal operating conditions and only diverts high-voltage surges to the ground. The absence of gaps reduces the risk of corona discharge and enhances the device's reliability by minimizing potential points of failure.

In contrast, other types of arrestors, such as ceramic and polymer, may incorporate internal structures that can create gaps or use multiple components in series, making them less effective in certain circumstances compared to the seamless configuration of metal oxide arrestors. Silicon dioxide arrestors may also include some variability in design that does not consistently eliminate gaps. Thus, the metal (zinc) oxide arrestor stands out as the type specifically noted for its uninterrupted design and superior performance in protecting electrical systems from lightning strikes and voltage surges.