Which of the following is not a component workers may encounter in substations?

High-voltage pylons are not typically considered components that workers interact with directly within substations. Instead, they are part of the transmission system that carries high-voltage electricity over long distances, often acting as support structures for overhead power lines. In contrast, substations contain critical electrical equipment including transformers, neutral reactors, and circuit breakers, which play essential roles in voltage regulation, power distribution, and protection of the electrical grid.

Transformers are necessary for adjusting voltage levels, neutral reactors help to stabilize and balance the system, and circuit breakers are vital for controlling and protecting electrical circuits by interrupting the flow of electricity during fault conditions. Therefore, while high-voltage pylons are integral to the overall power transmission infrastructure, they are not components that workers would typically encounter when working directly within a substation.