In industrial settings, electrical and instrumentation (E&I) cable trays or bridge racks play a critical role in organizing and supporting power, control, and signal cables across facilities. People use them in many buildings and work places to give cables a steady place to run. Cable trays come in different types: Materials: They can be metal (like steel with a coating, or stainless steel), plastic (like. Cable trays are structural systems used to support insulated electrical cables used for power distribution, communication, and control. These unassuming structures play a vital role in ensuring the safe and efficient transmission of power and data in a variety of industrial settings.