What type of electrical conductor is common in older systems?

In older electrical systems, steel conductors were commonly used due to their availability and cost-effectiveness at the time. Steel has a high tensile strength and was favored in many applications for structural support, especially in conduit and cable trays. However, while steel can conduct electricity, it's not as efficient as other materials like copper or aluminum.

Older installations often used steel for specific applications, including grounding and certain types of overhead power lines. The fact that steel is magnetic also allows it to serve specific purposes in certain electrical installations, adding to its historical usage. Nonetheless, for electrical conduction, traditional materials like copper and aluminum have largely taken precedence in modern applications due to their superior conductivity, resistance to corrosion, and overall effectiveness in transmitting electrical power. Thus, while copper and aluminum are more common today, steel remains associated with older electrical systems.