PV Wire Management Systems Explained

When you’ve got thousands of feet of PV wire strung up for seemingly endless acres, keeping them organized and protected is crucial. 

The best wire management plan relies on understanding the terrain, project size, complexity, layout, and other factors. Depending on the project, solar EPCs have several wire management options, from open-air clips and ties to comprehensive conduits and trays. Regardless of the style, these systems organize and protect cables for the life of the solar system. 

The result? Cleaner, manageable layouts, more efficient repairs and replacements, and safer sites over the long term. 

S Clips 

S clips are a low-cost and effective solution to keep wires and cables in place. 

The clips are usually made from stainless steel, which is strong and resists corrosion, making them great for outdoor use. Other options include aluminum alloys or even UV-resistant plastics. 

Crews like S clips because they’re easy to install without tools, attaching to the back of the solar panel or onto the racking. They’re also reusable, allowing workers to remove and reattach clips during maintenance, repairs, or replacements. 

Multi-Faceted Fasteners 

The allure of S clips lies in their simplicity. 

They’re small enough to hide under panels and along racking and perform well across many environments and temperatures. Certain constructions also work in harsh areas, including in or near salt water. 

Unlike more expensive wire management systems, S clips don’t require other tools to install. This makes them easy for even inexperienced workers to use. Removal is almost as easy, requiring only a screwdriver to pop the clip off the panel or racking. 

Though the clips only hold a few wires in place, they do an excellent job of preventing sagging along the cable line. However, crews must be careful to avoid accidental nicks or scrapes caused by the clips. Normally, they’re coined or smoothed to prevent damage but could cause problems over time or during severe weather. 

Hanger Systems 

Like S clips, wire hanger systems hold wires in place, but do it on a larger scale. 

Made from galvanized steel and coated with PVC, hangers are extremely durable and weather-resistant. The PVC protects the underlying steel core against exposure and ensures wires stay damage-free. 

Unlike S clips, which can hold two or three wires, hangers can hold many safely – including large-gauge cables. They’re cost-effective, reusable, easy to install without tools, and can bend to fit nearly any configuration. Hangers also perform well across many environments, including challenging terrain. 

To install hangers, workers first need to install a messenger wire. Though it doesn’t carry current, the steel cable shoulders the weight of all the cables to reduce sagging. It also provides a steady, safe spot to mount hangers that isn’t part of the racking or the panel itself. Once the messenger wire is in place, workers bend the hanger into the shape they need and hang it. 

Cable Ties and Locks 

Most people are familiar with plastic or nylon zip ties used for DIY projects, but solar cable ties are much stronger. 

Made from high-quality, durable, and UV-resistant plastic, these one-time-use ties secure cables directly to the solar racking. They’re chemical, water, and sunlight resistant, and more rugged ties could work in colder temperatures. 

Keep in mind that not all cable ties are equal. Low-quality ties, like the nylon ones hiding in your junk drawer, will eventually become brittle, causing them to break. This is especially true in areas where snow and cold weather are a threat and regions with high UV exposure. 

Unlike S clips and hangers, cable ties are a one-and-done product. Crews must replace them every time they complete work. 

Cable Locks 

Cable locks use a tool-free locking mechanism to hold ties in place, with additional room for slack. 

Depending on the company and the style, cable locks can look or act differently, but the overall logic is the same. Most are easy to install and reusable, utilizing locks and tie lines to hold cables in place and prevent accidental removal. 

Despite the similar design to cable ties, cable locks will last for the life of the panels, generally 20 to 25 years. 

Cable and Wire Trays 

Sometimes, open-air solutions aren’t the best way to protect solar wires.  

In those situations, especially in harsh environments and areas where digging isn’t possible, wire and cable trays make all the difference. 

Unlike conduit, which requires digging and burying wires, cable trays are aboveground installations. Workers connect the tray pieces, lay the wire in, and move along. The cables are safe from physical damage, including scrapes, abrasions, crushing, and even pests like rodents. Beyond physical damage, trays protect cables from wind, snow, sun, and other weather-related issues. 

Solar developers can choose either metal or plastic trays, depending on how much flexibility and strength they need. But no matter what material installers select, the cables inside are safe and organized. Best yet, if wires need replacement, workers can quickly access the tray. 

Conduit 

For the ultimate utility-scale solar cable protection, conduit is king. 

To install conduit, workers dig trenches in the ground and lay metal or PVC tubing. Next, workers fish the PV wire through the conduit from the solar panel to the combiner box. The resulting installation offers stellar protection from crushing, abrasion, UV, temperature changes, chemicals, and pests for the wire’s usable lifespan. 

Conduit keeps wire safe and sound but is more expensive than other wire management methods and is slower than open-air methods. Conduit also doesn’t work for certain solar sites, including those with rough terrain or brownfield sites. 

Wire Management Boxes 

Protecting wire is vital, but connection points are equally important. 

Combiner boxes are a staple at commercial, industrial, and utility-scale solar installations. Depending on the layout, they can hold dozens of wires in place, alongside fuse assemblies, buses, and even system monitoring equipment. 

When installing wire management boxes, placement is important. Every installation is different, and boxes must be ready to address unique challenges. From paint color and box size to breather vent placement and mounting position, every decision impacts performance and lifespan. 

Many Options, One Mission 

No matter what solutions installers choose, the goal is always to prevent wire damage. 

Wire management systems do a lot to prevent damage, but they aren’t perfect. Accidents happen, nicks occur, and wires pinch, leading to potentially dangerous situations like arcs, faults, and other issues. 

Damaged wires don’t always immediately cause problems – nicks in a conductor’s insulation take time to develop. Leaks, corrosion, pinches, abrasions… they can all eventually create delays, lost profits, and put people at risk. 

Crews should trust monitoring systems to track trends and spot abnormalities but should perform scheduled inspections, too. Beyond looking for obvious damage, workers should be on the lookout for other issues, including: 

  • Sharp edges on clips, ties, locks, and other materials 
  • Signs of aging on wire management systems, including peeling coatings, insulation pulling away, chipping, or nicks 
  • Damage to PV wire conductors, such as pinching, abrasions, nicks, and other wear 

Most importantly, work with local code departments and follow NEC guidelines. Keeping an eye on the regulations will ensure that teams safely manage solar power wires and cables.

Installing PV Wire: Direct Burial, Hangers, or Conduit?

PV wire doesn’t seem like a big deal, but moving generated power from solar panels to the electrical grid would be impossible without it. 

To the untrained eye, installing thousands of feet of wire seems like a pretty straightforward process. But maximizing its performance depends on several factors, including: 

  • Environmental Conditions  
  • Cost Considerations  
  • Ease of Installation  
  • Project Size

Depending on the situation, solar EPCs have a few installation options, including direct burial, conduit, and hangers. 

Direct Burial Installation 

When solar developers directly bury PV wires, they install them in trenches underneath the panel rows. 

Direct burial wire is designed for underground installation without a conduit. To ensure the wire is up to the task, it undergoes rigorous testing to earn a specific UL mark. In this case, the mark signifies the wire can withstand abrasions, crushing, moisture, chemicals, and other hazards. 

Solar companies like direct burial wire because it’s a low-cost and easy way to install electrical wiring. Workers only need to dig a trench along the panel aisle near the racking, place the wire, and cover it back up. But as easy as it is, direct burial wire isn’t appropriate for every application. 

The Good and the Bad of Direct Burial Wire 

Soft soil compositions with relatively few rocks are the best conditions for direct burial wire. Sandy soil is also a good option because it drains quickly. Drainage is vital for underground wire installations because moisture can damage wire insulation and jacketing over time. 

Direct burial wires also run the risk of damage from environmental hazards. Sharp rocks could nick wire insulation, allowing moisture to get in. Large rocks can crush the wire and its insulation, hurting performance. Even damage caused by rodents chewing on the wire can potentially create faults. 

Damage could lead to less electricity generated and create unsafe conditions. It also costs crews time, money, and long-term production since they must visit the site, dig up damaged wires, and repair or replace them. 

Underground Conduit Installation 

Conduit installation is similar to direct burial, but instead of putting the wires in the ground, they’re fished through metal or PVC tubes. 

The tubing provides an additional layer of protection on top of the wire’s standard thick insulation and works well in rocky, moist, or corrosive environments. Typically, conduit is used when crushing, abrasion, or other threats are an issue. Beyond soil, conduit protects the wire from rodents, temperature fluctuations, and accidental damage from digging. 

Unlike direct burial situations, workers can easily replace or repair wires if something goes wrong – without digging. Crews only need to pull the wire out, replace it, and fish it through the conduit pathway. 

Like any other electrical project, local regulations may dictate conduit use. Requirements could change from one municipality to the next. The National Electrical Code (NEC) also has specific standards, so keep them in mind. 

More Protection, Higher Costs 

Encasing wires in conduit offers better protection than insulation alone, but makes solar projects more expensive. 

Not only do you have to buy enough for the entire site, you need people to install it. This means digging trenches, burying the conduit, then pulling wires through the tubing to connect everything. And as utility- or community-scale solar sites get bigger, so do the associated costs and timelines. 

Conduit is also not as flexible as direct burial wire, making it harder to use on slopes and curves. Shovels or excavators could also accidentally puncture metal or PVC conduit, damaging the contained wire. 

Cable Hangers 

Hangers come in many shapes and sizes, using galvanized steel coated with thick PVC to safely hold PV wires in place from the solar panel to the combiner box. 

Unlike conduit, workers can easily bend hangers to fit whatever shape they need. And unlike direct burial and conduit solutions, hangers don’t require any digging. They connect directly to the racking underneath the solar panels and provide a cost-effective way to string PV wire quickly across difficult terrain. This makes them useful in areas where the ground isn’t suitable for digging, like brownfields

Depending on the number of wires carried along the pathway, messenger wires might be necessary. Unlike PV wire, messenger wires don’t carry any current – they provide strength and support to keep wires in position. 

Maintenance and repair work is also easier for operators because the wires live in the open air. Workers can find damaged wires, remove them from the hanger system, and replace them without additional equipment. 

PV Wire Hanger Considerations 

As with any electrical job, PV wire hangers fall under NEC guidelines. 

According to NEC Article 690.31 (C) (1) (b), “Exposed cables sized 8 AWG or smaller shall be supported and secured at intervals not to exceed 600 mm (24 inches) by cable ties, straps, hangers or similar fittings.” 

The rules are slightly different for wires bigger than 8 AWG, allowing hangers up to every 54 inches. For added support, messenger wires can help carry some of the weight. 

Depending on the location of the solar array, code enforcement could apply other rules. Contact your local codes department to avoid any potential issues. 

Above-ground wires also face several potential issues, including contact with people and vehicles and severe weather. Buried wires are typically hidden, but hanging wires don’t have the same type of protection. This leaves them open to damage from sun, wind, rain, snow, vandalism, and accidental contact. 

What Impacts Solar Wire Installation? 

No two installations are alike, but knowing what you’re getting into before putting shovels in the ground can make mistakes avoidable. 

Environment 

Soft soil without much moisture is well-suited for direct burial projects. If the soil is rocky, struggles with drainage, or risks contact with chemicals, conduit makes sense. If the land is rocky, too wet, or at a brownfield site, hangers are a safe, cost-effective choice. 

Cost 

Direct burial is a low-cost option but requires laborers to dig trenches. Hangers are also cost-effective but leave wire out in the elements and exposed to other dangers. 

Conduit is pricier and requires labor, time, and equipment. However, it offers solar systems the best protection from damage and exposure. 

Project Size 

Bigger sites mean more work and longer timelines. Worse yet, delays can occur if crews run into unexpected issues. 

Smaller community-scale solar energy projects take less time to wire compared to utility-scale solar projects. However, smaller sites may benefit from the added protection conduit offers without a massive hit to the bottom line. As sites become larger, costs increase dramatically, forcing project developers to limit expenses. 

Code Regulations 

Although the NEC is an excellent guidebook, follow local and state codes to avoid mistakes. 

Failing to do so could result in violations, leading to work delays, fines, or other problems. 

Know Your Surroundings 

As solar sites spring up across the United States in brownfields, farmland, and even on water, teams should carefully determine how to set up their arrays.

Whether it’s a utility company with a small solar farm in the rolling hills or a large-scale developer repurposing brownfields, having the right manufacturing partner makes a huge difference. 

Good partners understand community, industrial, and utility-scale installations and act as a guide. They can also field questions and offer insight throughout the blueprinting, development, and troubleshooting processes. 

Most importantly, companies can keep every solar job on time and within budget.