Okay, this is a complex situation involving grounding and bonding in a transfer switch and meter can setup. It's important to get this right for safety and code compliance. I will answer your questions in order, providing relevant code references where possible.

Disclaimer

I am an AI chatbot and cannot provide electrical advice. This information is for educational purposes only. Consult with a licensed electrician for any electrical work or installations.

Understanding the System

Before answering your questions, let's clarify a few things:

GEC

Grounding Electrode Conductor (your #4 solid bare Cu wire) - connects the electrical system to a grounding electrode (ground rod, water pipe, etc.).

Bonding

Connecting metallic parts of the electrical system together to create a low-impedance path for fault current. This is crucial for safety, allowing overcurrent devices to trip quickly in the event of a ground fault.

Meter Can

The enclosure where the electric meter is housed.

Transfer Switch

A device that switches the source of power to a building (e.g., from utility to generator).

Answers to Your Questions


GEC Connection at Transfer Switch Grounding Bar Options



Yes, you can likely use a larger grounding bar. Here's why: The purpose of the grounding bar is to provide a central location for connecting all grounding and bonding conductors within the enclosure. As long as the new grounding bar is properly sized (ampacity and physical size) and securely bonded to the metal enclosure of the transfer switch, it can be used. The new Grounding bus has to be listed. Important

Make sure the new grounding bar is specifically listed for use as a grounding bar in an electrical enclosure.

Relevant Code (NEC 250.8)

"Connection of Grounding and Bonding Equipment. Grounding conductors and bonding jumpers shall be connected by exothermic welding, listed pressure connectors, listed clamps, or other listed means. Connection devices or fittings that depend solely on solder shall not be used."2.

Removing Existing Bonding Terminal and Replacing with Larger Bar



Yes, but with caution and a qualified electrician's assessment. Here's why this is tricky: Bonding is Critical

The transfer switch enclosure must be properly bonded to the grounding system. Removing the existing bonding terminal could compromise this bond if not done correctly.

Enclosure Listing

The enclosure is likely listed and tested with the specific grounding terminal that is provided with the transfer switch. Replacing it with something different could void the listing of the enclosure.

Factory Tack Welded Angle

You mentioned the terminal block is factory tack-welded to a angle. This implies the manufacturer intended it to be the primary bonding point.

NEC 250.8 covers the connection requirements for grounding and bonding equipment, as stated above.3. Ground Wire to Meter Can and GEC Connection at Transfer Switch



The meter can likely DOES need a grounding electrode conductor connected to the neutral. NEC 250.24(C) covers the grounding requirements for service equipment. Generally, the grounded conductor (neutral) is required to be connected to a grounding electrode at the service equipment (which is the meter can in your case). This is in addition to the GEC at the transfer switch. Reasons For



Safety

This provides a low impedance path for fault current.

Code Compliance

Many jurisdictions require a grounding electrode connection at the service equipment.

Redundancy

Provides an additional layer of protection if the connection at the transfer switch were to fail.

NEC 250.24 (C)(1) Location. The grounding electrode conductor shall be connected at any accessible point from the load end of the service drop or service lateral to and including the terminal or bus to which the grounded service conductor is connected at the service disconnecting means.

Important Considerations and Recommendations



Consult a Licensed Electrician

This is the most important thing. Your situation is complex and requires a qualified electrician to assess the installation, ensure it meets code, and is safe.

Local Jurisdictional Authority (L.J.H.A.)

Since the L.J.H.A. wants the G.E.C. connected at the transfer switch, it is best to follow their direction and get written approval if the installation does not follow the code (as long as the installation maintains a low impedance path and is safe).

Manufacturer's Instructions

Always follow the manufacturer's instructions for the transfer switch and any grounding/bonding components. These instructions will often provide specific guidance on proper installation.

Testing

After any changes to the grounding/bonding system, it is essential to have the system tested by a qualified electrician to ensure it is functioning correctly.

In Summary:

While it may be possible to use a larger grounding bar in the transfer switch, and even replace the existing terminal, this requires careful consideration and assessment by a qualified electrician. The meter can likely* needs a grounding electrode connection. The most important thing is to prioritize safety and code compliance. Consulting with a licensed electrician and following the manufacturer's instructions are crucial for a safe and compliant installation. Flag for review