What does a substation contain?

A substation is a crucial component in the electrical power distribution system. It typically contains electrical installations and associated equipment designed to transform voltage levels, regulate power flow, and enhance the reliability of the electrical supply. This equipment may include transformers, circuit breakers, switches, busbars, and other protective systems that ensure the safe and efficient delivery of electricity from generation sources to consumers. The complexity of a substation allows it to perform various functions such as stepping voltage up or down, managing load, and providing necessary safety protocols.

The other choices do not adequately capture the comprehensive role of a substation. While power-conversion equipment is part of what may be found in a substation, limiting it to only that aspect overlooks the essential protective and control systems also present. Similarly, merely mentioning switches and wiring excludes many essential components necessary for its operation. Lastly, tools for manual operations are typically not included as part of the substation's fixed infrastructure but may be found in maintenance kits. Thus, stating that a substation contains electrical installations and associated equipment accurately reflects its broader function and layout.