What should be done first when troubleshooting an electrical system?

When troubleshooting an electrical system, the first essential step is to turn off the power to the system. This action ensures the safety of the technician working on the system, preventing any risk of electric shock or injury while diagnosing the problem. By disconnecting the power supply, you create a safe environment to inspect and troubleshoot the system without the danger of live electricity.

Once the power is confirmed to be off, other troubleshooting steps can be carried out more safely, such as checking circuit breakers, measuring voltages, and inspecting wiring connections. These actions can lead to identifying the problem without the risk that would come from working with live equipment. Safety is paramount in electrical troubleshooting, and turning off the power first establishes that safety before proceeding with any further diagnostic steps.