Grounded conductors must meet certain requirements. It helps to remember that they are, as the name suggest, a type of conductor. From this fact, you might conclude that the insulation on these conductors must be as suitable to the application as is the insulation on the other conductors in the circuit. Your conclusion would be correct. That’s an actual requirement [200.2]. The only difference should be the color of the insulation.
When you terminate grounded conductors, it’s often necessary to pigtail them to preserve electrical continuity. It’s insufficient to bring a grounded conductor into a metallic enclosure, connect it to a “neutral lug,” and continue the grounded conductor from that connection. This, in fact, is expressly prohibited. The reason becomes clear when you consider what happens to that grounded conductor if you remove the enclosure. The same logic applies to raceway and cable armor.
It’s important to understand that the grounded conductor and the neutral conductor are not necessarily the same thing. Typically they are, but interchanging these terms can lead to lethal mistakes. Here’s the difference:
• The grounded conductor is one that is intentionally grounded.
• The neutral conductor one that’s connected to the neutral of the system and intended to carry current under normal conditions.