Solar PV Installation Safety

• With an increase in clean energy options comes the need for safe installation of the technologies.

By Brianne Deerwester, Contributor

The dependence on modern electronic devices and the rapid advancements made to emerging technology has significantly increased the energy demands placed on homes and commercial buildings. Adapting to the ever-evolving future of energy requires efficient and clean energy.

Energy storage systems and photovoltaic (PV) solar panels can allow you to tap into efficient energy and reduce your energy dependency. When solar panels are paired with energy storage systems, they automatically provide power to essential devices in your home or business during power outages or peak power.

With an increase in clean energy options comes the need for the safe installation of the technologies. According to the U.S. Bureau of Labor Statistics, there is a 51% expected growth in solar PV installer jobs by 2029, making it the third fastest-growing occupation. Between 2011 and 2019, 650 solar PV installers were injured on the job, and 51% of the injured solar PV installers were only on the job between one to five years. It is imperative to educate these installers on the importance of installing solar PV systems safely.

Know the Dangers

Before installing solar PV, be sure to locate all overhead power lines. Between 2011 and 2021, ESFI found that 46% of all electrical fatalities were caused by contact with overhead power lines. Always consider all overhead lines to be live, energized, and dangerous.

Keep yourself and your equipment 10 feet away from all overhead lines. Carry ladders and other equipment horizontally when on the ground to avoid contact with power lines. Always stay at least 35 feet away from any downed power lines. Never walk or climb on a solar PV panel and stay at least 10 feet away from solar installations. As a reminder, solar disconnects only disconnect buildings from PV panels. Panels can still generate power. Always be aware of bi-directional current flow and mark all bi-directional meters.

Solar PV connectors are a vital part of a PV system, as they provide connections between the arrays. There is no universal standard for PV connector design, and in some cases, connectors with high operating temperatures may be the only warning sign of PV failure.

Unskilled or untrained workers installing PV can lead to problems. Improper installation and PV connector issues can cause fires and injure workers, so proper installation is imperative. To help ensure the safety of yourself and others, follow these tips on recommended installation practices and warning signs of failure:

Recommended Installation Practices

• Use the same manufacturer or manufacturer-provided tools.
• Use proper tools in accordance with the manufacturer’s instructions.
• Follow the connector manufacturer’s instructions.
• Use only connector parts of the same manufacturer. Interoperability issues may occur when using connectors from different manufacturers.
• NEC Section 690.33/UL 6703 requires that two parts of connector pairs must be tested together and certified for intermatability. Items must be listed and, to be listed, they must be able to work together.
• Ensure materials are kept from becoming soiled before installation. If damaged, soiled, or exposed to water before installation, there is no way to clean them.

Why Failures Happen

• Soiled and dirty connectors
• Improper installation
• Lack of training
• Faulty materials
• Improper installation tools
• Mismatched connectors
• Counterfeit connectors

Warning Signs of Failure

• Loose or disconnected connectors
• High temperatures and melted, discolored, or cracked casing
• High resistance due to soiling, corrosion, foreign particles, or improper surface contact on metal contacts
• Increased alarms on monitoring systems (ground, isolation, loss of energy yield, and/or arc faults)
• Moisture or water ingress due to broken seal and/or separated connectors
• Material degradation and exposure to elements

Diagnosing and Preventing Connector Failures

• Identify high temperatures due to increased resistance. Use thermal imaging to find abnormal temperature readings. Connectors operating over 85°C may be failing.

• Use thermal imaging to find connectors that are hotter than others. Note that thermal imaging on the ground can identify issues. Drone imaging may miss connector issues that are underneath modules.
• Visually inspect connectors to locate any physical or heat-related damage. Issues with connectors can cause power loss and fires or create ground faults that could be lethal. These issues impact performance, cause downtime, and have commercial and monetary impacts.

As solar PV installer jobs are the third fastest-growing occupation, it is imperative to properly train workers to avoid preventable workplace injuries and fatalities. Working with electricity is extremely dangerous, so it’s critical to hire qualified electrical workers and thoroughly train anyone conducting work on or around electricity.

At the workplace or job site, overhead power lines, unexpected contact with electricity, working on energized parts, ground faults, and damaged wiring account for 92% of electrical fatalities. These accidents can be avoided by training workers and empowering them to follow safe work practices, including knowing when to say when, testing before you touch, following the hierarchy of controls, and following proper lockout/tagout procedures.

For access to free electrical safety materials you can share with your colleagues to make your workplace a safer environment, visit esfi.org.

Brianne Deerwester is Communications Coordinator, Electrical Safety Foundation International (esfi.org).