The wire must be able to come out beyond the surface of the box at least 3". From there, you can run a /2 w/ground cable to this. When attempting to replace an electrical outlet, an issue may arise due to inadequate wire length inside the junction box, which does not meet the minimum requirements. Required Wire Length: The National Electrical Code requires at least 6 inches of wire inside. WAGO 221 Lever Nut Kit: https://geni. A 'pigtail' is simply an extension that is added to a piece. So, what happens when you go to change a device and the wires are just too short? There are generally two ways to fix this: Sometimes you can loosen the box connector at the back of the box and pull more wire out. In this video I show you numerous ways to fix wires that are too short in an electrical box.