Solar power is on the rise. Learn to work safely around it.<\/h1>\n
If you work on or around building exteriors, you are more and more likely to encounter rooftop solar installations. Small-scale solar systems at ground level are also increasingly common. Learn to work safely near solar equipment to prevent costly damage and dangerous electrical contacts.<\/p>\n<\/div>
<\/i><\/i><\/span>Basic solar components and precautions<\/span><\/a><\/h4><\/div>\n<\/div><\/div><\/div><\/p>\n<\/div>Learn to recognize solar power system components.<\/strong><\/div><\/div><\/p>\n<\/div>A solar power system can generate enough electricity to injure or kill if it passes through a human body. These systems are being installed by dozens of different companies and even by DIYers, so there is no one standard setup for all installations. Learning to recognize the typical components of these systems will help you work safely around them. Here\u2019s an overview:<\/p>\n
\n- Photovoltaic (PV for short)<\/strong> is the most common type of solar power generation in the U.S. PV cells convert light into electricity.<\/li>\n
- PV cells are what you see inside glass-faced solar panels.<\/strong> Each cell is about 4\u201dx4\u201d and there are typically between 24 and 42 cells per panel.<\/li>\n
- A set of PV panels is called an array<\/em>.<\/strong> Special mounts hold arrays to the roof or the ground.<\/li>\n
- Power cables run from the array through conduits.<\/strong> The conduits lead into a building and\/or to other equipment, such as combiners, inverters and meters.<\/li>\n<\/ul>\n
Locate all equipment.<\/strong><\/p>\n<\/div><\/div>\n<\/div>Solar power systems can carry live electrical current even when the sun is not shining. So no matter when you are working, you\u2019ll want to know the entire route that electricity from the PV system travels. Before beginning work, ask the building owner or manager to point out the arrays and all related equipment.<\/p>\n
Keep your distance.<\/strong><\/p>\n<\/div><\/div>\n<\/div>Once you know the location of system components, keep ladders, tools, supplies and equipment away from them. Do not place cans or tools on or near solar arrays, and avoid contact with cable conduits and\/or pipes. If possible, maintain a 2- to 3-foot safety perimeter around PV panels.<\/p>\n
Before starting any job, locate solar power components so you can stay a safe distance away from them.<\/h4>\n<\/div><\/div>\n<\/div><\/div><\/div><\/div><\/div>\n<\/div>![\"Basic](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/basic_solar_image.jpg\")
<\/div><\/div><\/p>\n<\/div><\/div><\/div><\/div>![\"Basic](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/basic_solar_image2.jpg\")
<\/p>\n
\nConduit carries electricity from PV arrays to an inverter mounted in a utility closet. At right is a DC disconnect.<\/p>\n<\/blockquote>\n<\/div>\n
<\/div><\/div><\/div><\/div>\n<\/div><\/div><\/div><\/i><\/i><\/span>System types and equipment<\/span><\/a><\/h4><\/div><\/div>\n<\/div>Solar power systems come in two basic types,<\/strong> depending on whether the electricity they produce flows into the electrical grid, or into a bank of batteries for local use:<\/p>\n\n- Grid-tied or grid-connected:<\/strong>\u00a0These systems are by far the most common. As the name implies, these systems are connected to the larger electrical grid. The power they generate is converted from direct current (DC) to alternating current (AC) through an inverter<\/em><\/strong>. The surplus AC electricity the system generates is fed from the inverter back into the grid via the utility\u2019s meter.<\/li>\n
- Standalone or off-grid:<\/strong>\u00a0DC power from these systems is also changed to AC power so it can be used to run lights and appliances. A battery bank<\/em><\/strong> stores power for use when the system is not generating electricity. Battery capacity in relation to cost is rising fast, which means that off-grid systems may soon become more popular.<\/li>\n<\/ul>\n
Solar equipment for all system types is found on building exteriors and indoors.
\n<\/strong>In any PV system, wires from multiple panels are gathered through a combiner box whose output cable runs through a conduit down from the roof to an inverter. For a grid\u2011tied system, the next point on the circuit is a disconnect switch that can be opened by utility personnel. This switch isolates the PV system from the grid in order to safely work on grid equipment. Next on the circuit is the utility\u2019s electric meter. Meters and disconnects are usually located on the building exterior, while inverters are typically inside a garage or basement. For buildings with multiple meters, such as apartments and condominiums, meters may be located indoors.<\/p>\nFor a standalone system, the conduit will lead from the inverter to the battery bank, currently always located indoors (garages are a favorite spot). But again, electrical storage technology is evolving very fast, so when working around a building with off-grid solar, be sure to ask where the bank is located and where the conduit or cable bundle enters the building.<\/p>\n
Be alert for combiner boxes, inverters and meters. Off-grid systems also use batteries.<\/h4>\n<\/div><\/div><\/div><\/div>\n![\"Solar](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/system_types_image.jpg\")
<\/div><\/div><\/div><\/div>![\"Smart](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/system_types_image2.jpg\")
<\/p>\n\nThis grid-tied system integrates a \u201ctime of use\u201d smart meter on an external wall. At left is an AC disconnect.<\/p>\n<\/blockquote>\n<\/div>
<\/div><\/div><\/div><\/div>\n\n![\"System](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/system_types_diagram.jpg\")
<\/p>\n<\/blockquote>\n<\/div>\n
<\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/i><\/i><\/span>Rooftop solar safety<\/span><\/a><\/h4><\/div><\/div>\n<\/div>Rooftop PV arrays and their associated cables and equipment are easily damaged.<\/strong>
\nIf you\u2019re performing gutter or downspout cleaning or repair, exterior painting or plastering, or any other work that takes you near a solar rooftop, keep these tips in mind:<\/p>\n\n- Protect panels and mounts.<\/strong> The top surfaces of the panels in solar arrays are made of glass that protects the PV cells inside from wind and weather. The glass of the panels is tempered (hardened), but will crack or break if a heavy object falls on them. Once this happens, the panel is destroyed and must be replaced. The mounts under the panels should also be treated with caution. Make sure they don’t get bent or broken. If possible, maintain a 2- to 3-foot safety perimeter around panels and mounts.<\/li>\n
- Avoid cables and conduits. Look out for cables (usually in conduits) leading away from the array.<\/strong> These carry electrical current strong enough to severely injure or kill you if you make contact with the wires inside. Keep in mind that conduits may run from a rooftop down the outside of a building, so your precautions shouldn’t stop at the edge of the roof.<\/li>\n<\/ul>\n<\/div><\/div><\/div><\/div>\n
![\"Roof](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/rooftop_solarimage.jpg\")
<\/div><\/div><\/div><\/div>![\"Roof](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/rooftop_solar_image2.jpg\")
<\/p>\nTake care around rooftop thermal systems as well.<\/strong>
\nRooftop thermal systems are used to heat water. The simplest ones, often called \u201cpassive thermal,\u201d move water through an array of narrow pipes on which sunlight is focused through glass. Other types, collectively called \u201cactive thermal,\u201d use a pump to move the water through the pipe system. Take care around these installations and their input and output pipes.<\/p>\nKeep tools, supplies and equipment away from rooftop solar panels, mounts, cables, conduits and water pipes.<\/h4>\n<\/div>\n
Learn to recognize solar power system components.<\/strong> A solar power system can generate enough electricity to injure or kill if it passes through a human body. These systems are being installed by dozens of different companies and even by DIYers, so there is no one standard setup for all installations. Learning to recognize the typical components of these systems will help you work safely around them. Here\u2019s an overview:<\/p>\n Locate all equipment.<\/strong><\/p>\n<\/div> Solar power systems can carry live electrical current even when the sun is not shining. So no matter when you are working, you\u2019ll want to know the entire route that electricity from the PV system travels. Before beginning work, ask the building owner or manager to point out the arrays and all related equipment.<\/p>\n Keep your distance.<\/strong><\/p>\n<\/div> Once you know the location of system components, keep ladders, tools, supplies and equipment away from them. Do not place cans or tools on or near solar arrays, and avoid contact with cable conduits and\/or pipes. If possible, maintain a 2- to 3-foot safety perimeter around PV panels.<\/p>\n Conduit carries electricity from PV arrays to an inverter mounted in a utility closet. At right is a DC disconnect.<\/p>\n<\/blockquote>\n<\/div>\n Solar power systems come in two basic types,<\/strong> depending on whether the electricity they produce flows into the electrical grid, or into a bank of batteries for local use:<\/p>\n Solar equipment for all system types is found on building exteriors and indoors. For a standalone system, the conduit will lead from the inverter to the battery bank, currently always located indoors (garages are a favorite spot). But again, electrical storage technology is evolving very fast, so when working around a building with off-grid solar, be sure to ask where the bank is located and where the conduit or cable bundle enters the building.<\/p>\n This grid-tied system integrates a \u201ctime of use\u201d smart meter on an external wall. At left is an AC disconnect.<\/p>\n<\/blockquote>\n<\/div> Rooftop PV arrays and their associated cables and equipment are easily damaged.<\/strong> Take care around rooftop thermal systems as well.<\/strong>\n
Before starting any job, locate solar power components so you can stay a safe distance away from them.<\/h4>\n<\/div>
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<\/i><\/i><\/span>System types and equipment<\/span><\/a><\/h4><\/div>
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\n<\/strong>In any PV system, wires from multiple panels are gathered through a combiner box whose output cable runs through a conduit down from the roof to an inverter. For a grid\u2011tied system, the next point on the circuit is a disconnect switch that can be opened by utility personnel. This switch isolates the PV system from the grid in order to safely work on grid equipment. Next on the circuit is the utility\u2019s electric meter. Meters and disconnects are usually located on the building exterior, while inverters are typically inside a garage or basement. For buildings with multiple meters, such as apartments and condominiums, meters may be located indoors.<\/p>\nBe alert for combiner boxes, inverters and meters. Off-grid systems also use batteries.<\/h4>\n<\/div>
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<\/p>\n<\/blockquote>\n<\/div>\n<\/i><\/i><\/span>Rooftop solar safety<\/span><\/a><\/h4><\/div>
\nIf you\u2019re performing gutter or downspout cleaning or repair, exterior painting or plastering, or any other work that takes you near a solar rooftop, keep these tips in mind:<\/p>\n\n
<\/p>\n
\nRooftop thermal systems are used to heat water. The simplest ones, often called \u201cpassive thermal,\u201d move water through an array of narrow pipes on which sunlight is focused through glass. Other types, collectively called \u201cactive thermal,\u201d use a pump to move the water through the pipe system. Take care around these installations and their input and output pipes.<\/p>\nKeep tools, supplies and equipment away from rooftop solar panels, mounts, cables, conduits and water pipes.<\/h4>\n<\/div>\n
![\"Ground](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/ground-level_solar_image.jpg\")
<\/p>\n![\"PV](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2020\/05\/pv_image.jpg\")
<\/p>\n![\"solar](\"https:\/\/domsafety.com\/contractors\/wp-content\/uploads\/2021\/03\/solar-roof.png\" "\\"solar")
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