What is the typical line voltage range mentioned for electrical systems?

The typical line voltage range for electrical systems, particularly in the context of transmission systems, generally includes voltages that are utilized for effectively transmitting electricity over long distances. Among the options provided, 69,000 volts represents a commonly used voltage level for medium voltage transmission lines.

This voltage level is significant because it strikes a balance between efficiency and safety for utility companies when distributing power from substations to end users. Voltages like 69,000 volts are often used to minimize energy losses due to resistance in the lines and also to maintain the infrastructure over long distances without excessive heat generation or equipment strain.

Other voltage levels provided, such as 12,000 volts, may be relevant for local distribution systems rather than transmission, while 45,000 volts and 138,000 volts are often seen in specific uses and also represent higher transmission levels. However, 69,000 volts is a well-established level in the medium voltage range often seen in many utility configurations.