You are right to be cautious! Here's a breakdown of why this is potentially problematic, even if some parts are technically listed

The Issues with "Kits" Like This:
Listing Doesn't Guarantee System Compatibility

Just because individual components (like the inverter or panels) might be listed by a recognized testing laboratory (like UL, ETL, CSA, etc.) doesn't mean the entire assembled system is. The listing applies to the specific device under specific conditions of use that the manufacturer submitted for testing. The compatibility and safety of the entire system is not covered by a listing of a component.

Unqualified Installation

The assumption is usually that a qualified electrician will install the system. These kits are often marketed towards DIYers. Incorrect installation introduces significant hazards.

Lack of Proper System Design and Permitting

A grid-tied solar system requires proper design considerations, including:

Load Calculations

Ensuring the existing electrical service can handle the additional load.

Overcurrent Protection

Properly sized breakers and fuses.

Grounding

Adequate grounding for the DC and AC systems.

Voltage Drop Calculations

Ensuring wire sizes are adequate.

Arc Flash Hazard Analysis

(Typically for larger systems, but good practice).These considerations are absolutely critical for safety and code compliance and are typically handled by a licensed electrician or solar installer. Kits often bypass this vital step.

AHJ Approval and Inspection

Grid-tied solar systems must be permitted and inspected by the Authority Having Jurisdiction (AHJ). This is often the local city or county building department. The AHJ ensures the installation meets code and is safe. Kits can make this process difficult or impossible if they are not properly documented or the components are not compatible.

Warranty Issues

If installed incorrectly, the manufacturer's warranty may be voided.

Potential for Shady Components

You may have to look up each individual component. Some manufacturers of solar equipment are more reputable than others. Some even make false claims about listing.

Specifically Addressing 110.3(B)

You're right to consider 110.3(B) which states that listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

The Problem

The "instructions" for listed components will not cover the integration of those components into a complete solar system unless the kit is explicitly listed as a system with specific installation instructions and limitations.

How to Respond

Here's a good approach:1.

Acknowledge the Question

"Yes, if a component is listed by a qualified testing laboratory, it indicates that the device meets certain safety standards when used as intended by the manufacturer."2.

Introduce the Complexity

"However, the key issue with solar kits, even if individual components are listed, is the system as a whole. The National Electrical Code (NEC) and local building codes require more than just listed components. They require a properly designed, permitted, and inspected system."3.

Emphasize the Importance of Expertise

"Installing a grid-tied solar system is not a simple DIY project. It involves understanding complex electrical principles, performing load calculations, ensuring proper grounding and overcurrent protection, and complying with all applicable codes and regulations. A qualified electrician or solar installer is essential to ensure the system is safe, efficient, and meets all code requirements."4.

Suggest Alternatives

"If you're interested in solar power, I strongly recommend consulting with a licensed electrician or solar installer. They can assess your needs, design a system that meets code, obtain the necessary permits, and perform the installation safely and correctly. This might be slightly more expensive upfront, but it will save you money and headaches in the long run, and ensure your system is safe and compliant."5.

Direct them to AHJ

"I also suggest contacting your local building department (the AHJ) to find out what their requirements are for solar installations, including whether these self-install kits would be compliant."

In Summary:

While a listed component is a necessary condition for a safe installation, it's not sufficient. A solar kit like the one you linked to is likely to create problems with code compliance, safety, and long-term reliability. Steer clear of these types of solutions. Flag for review