Electrical safety standards specify that at least 6 inches of free conductor must be left at each outlet, junction, or switch point. This measurement begins from the point where the cable sheath or raceway enters the electrical box. The length of wire left inside an electrical box is a matter of strict compliance, safety, and functionality. It takes the incoming power and safely distributes it to different circuits throughout your building. 12 Mechanical Execution of Work. However, in actual operation, problems such as loose terminals and broken terminals often occur, resulting in poor electrical connection and affecting power transmission.