What color screw would indicate a bonded panel?

The color green is used to indicate a bonded panel because green is the standard color for grounding and bonding components in electrical installations. When you see a green screw, it signifies that the connection is meant for grounding, ensuring that electrical energy has a safe path to the ground. This grounding is crucial because it helps to prevent electric shocks and provides a route for fault current, thereby enhancing the safety of the electrical system.

In contrast, the other colors do not correspond to the bonding or grounding specifications. Red and blue are typically used for other purposes in electrical systems, such as for hot conductors in multi-phase systems. Black is often used for hot wires as well. Therefore, green stands out as the designated color for grounding, making it the correct choice for indicating a bonded panel.