Let's break this down. You're dealing with a critical safety issue, so getting this right is vital. I am not a licensed electrician and this is not to be taken as electrical advise. Consult with a licensed electrical contractor.

Understanding the Cables & the Goal SEU (Service Entrance Underground) Cable

Typically has two insulated conductors (hot/ungrounded) and a bare conductor. The bare conductor usually serves as the neutral. SEU cable

is generally not rated for use as a grounding conductor. SER (Service Entrance Round) Cable

Typically has two insulated conductors (hot/ungrounded), an insulated neutral conductor, and a bare conductor. The bare conductor is used for equipment grounding.

Generator Transfer Switch at the Utility Pole

You want to install a transfer switch at the utility pole to switch the house's power source between the utility grid and a generator. This is an unusual setup, but it might be for specific reasons (lengthy run to the house, wanting the transfer point outside, etc.).

The Problem with Using SEU for a Transfer Switch with Generator

The core issue is the NEC (National Electrical Code) mandates a properly installed and sized equipment grounding conductor for safety. When you use a generator, you're essentially creating a new power source. This new power source must have a path to ground that will trip the breaker in a fault condition. SEU cable is not designed for this.Here's why SEU is problematic in this setup, combined with what the code is saying:1. Grounding Concerns

SEU is not designed for grounding. The bare conductor in an SEU is typically used as a neutral conductor.2.

Separation of Neutral and Ground

The NEC generally requires that the neutral and grounding conductors be separate from the service equipment onward (with certain very specific exceptions at the service entrance itself). Combining neutral and ground beyond the service entrance panel is a recipe for problems.3.

Fault Current Path

If you have a fault in your generator-supplied circuit, you need a dedicated ground wire to provide a low-impedance path for fault current back to the generator, tripping the breaker quickly. The SEU cable is not rated for that, which could create a potential electrocution hazard.

Code Implications NEC 250.4(A)(5): Effective Ground-Fault Current Path

This section is absolutely critical. It requires an effective ground-fault current path that is "intentionally constructed." The path must be permanent and continuous, have low impedance, and be capable of safely carrying the maximum ground-fault current likely to be imposed on it. Using the SEU cable as a combined neutral/ground would likely violate this.

NEC 250.24(A): Grounding Service-Supplied Alternating-Current Systems

This section details the requirements for grounding the service. It generally necessitates a grounding electrode system (ground rod, water pipe, etc.) connected to the service equipment.

NEC 250.30 Grounding Separately Derived AC Systems

This section specifically addresses grounding requirements when using a generator as a separately derived system. It requires the generator to have a grounding electrode conductor connected to the grounding electrode system.

NEC 338

This section covers service-entrance cable, including SE and USE. It does not generally allow the use of the bare conductor as both a neutral and a ground beyond the service entrance point.

The Likely Solution: SER Cable

The safest and most compliant approach is likely to replace the existing SEU cable with SER cable. This will give you the dedicated ground conductor you need for proper generator grounding. SER is designed for this, as it has separate neutral and ground conductors.

Important Considerations Utility Company Involvement

Installing a transfer switch at the pole is a task that

requires close coordination with the utility company. They may have specific requirements for the switch type, installation procedures, and safety protocols. You will likely need their permission and inspection. Local Codes and Inspections

Always check with your local building department to determine if any local amendments to the NEC are in effect. You will almost certainly need a permit and an inspection for this type of work.

Professional Installation

This is not a DIY project for the average homeowner. Incorrectly installed transfer switches and grounding systems are a serious electrocution and fire hazard. Hire a qualified and licensed electrician.

In Summary

Using the existing SEU cable for a generator transfer switch at the utility pole is likely not compliant with the NEC due to grounding requirements. The best approach is almost certainly to replace the SEU with SER cable to provide a dedicated grounding conductor. This is a project that requires a qualified electrician and close coordination with the utility company and local building department. Flag for review