Yes, using bare copper wire to secure a bundle of grounding conductors within an electrical panel is likely a violation of the National Electrical Code (NEC) and common electrical best practices. Here's why: NEC 250.8 Connection of Grounding and Bonding Equipment

This section requires that grounding and bonding conductors be connected using listed pressure connectors, terminal clamps, or other listed means. Simply wrapping bare copper wire is not a listed method and doesn't provide a reliable, low-impedance connection.

NEC 250.128 Identification of Equipment Grounding Conductors

While this refers to individual grounding conductors, the general principle is important. Grounding conductors need to be easily identifiable. Wrapping bare copper around them obscures the individual conductors and makes it harder to trace and inspect them.

Corrosion

Dissimilar metals in contact (like copper grounding conductors and the steel panel enclosure) can lead to galvanic corrosion. While a copper ground bus is acceptable, wrapping bare copper around the conductors creates more surface area for potential corrosion.

Mechanical Security

Wrapped wire can loosen over time due to vibration or thermal cycling. A proper connector provides a more secure and reliable connection.

Professionalism and Workmanship

Even if one could argue a technical loophole, using a wire wrap looks unprofessional and suggests a lack of understanding of best practices. Good electrical work is neat, organized, and uses appropriate materials.

What should be used instead? Ground Bars/Busses

The ideal solution is to use a properly sized and installed ground bar or busbar within the panel. All grounding conductors should be individually terminated to the ground bar using listed connectors.

Listed Grounding Connectors

There are various listed grounding connectors (e.g., split bolts, crimp connectors) specifically designed for joining grounding conductors. These connectors provide a secure, low-impedance connection.

Proper Sizing

The connectors and ground bar must be appropriately sized for the number and size of the grounding conductors.

Recommendation:

A qualified electrician should inspect the panel and replace the bare copper wire wrap with an appropriate grounding method that complies with the NEC and local codes. This will ensure a safe and reliable grounding system. It is also a good idea to verify the the correct size of ground bar and connections are being used. Flag for review