The construction site of the solar photovoltaic power generation system, like the construction site of other projects, has many unsafe factors, including many electric and non-electric dangers. The vast majority of photovoltaic system projects are constructed outdoors, in the wild or on the roof. When installing and testing photovoltaic power generation systems, we must always be alert to potential physical, electrical and chemical hazards that may occur, such as sun exposure, insects and snakes. Bites, bumps, sprains, falls, burns, electric shocks, scalds, etc., to name a few.
1. Common security hazards
(1) Physical hazards
When operating the photovoltaic power generation system outdoors, the electrical equipment is usually operated with hands or power tools. In some systems, related operations on the battery are also required. A little careless operation may cause burns to the operator. , electric shock and other physical hazards. Therefore, it is very important to use the tools correctly and safely and to take the necessary protective measures.
(2) Solar radiation
Photovoltaic power generation systems are installed in sunny places without shadows. Therefore, when construction work is carried out under the scorching sun for a long time, you must wear a sun hat and apply sunscreen to protect yourself from being burned by the scorching sun. In hot weather, drink plenty of water and take a few minutes of rest in the shade every hour of work.
(3) Insects, snakes and other animals
Wasps, spiders and other insects often inhabit the junction box, the outer frame of the photovoltaic array and the protective shell of other photovoltaic systems. In some remote fields, snakes also often appear. Likewise, ants will also inhabit the PV array foundation or around the battery box. Therefore, certain precautions need to be taken when opening the junction box or other equipment enclosure. Before working under or behind the photovoltaic array, you need to carefully observe the surrounding environment to avoid unexpected situations.
(4) Cuts, bumps and sprains
Many components of photovoltaic systems have sharp edges and corners, which may cause injury if you are not careful. These parts include the aluminum alloy frame of the battery module, the flange of the junction box shell, the burr of the bolt and the nut, and the burr of the bracket edge. Wear protective gloves, especially when drilling and sawing metals. In addition, when working under a low photovoltaic array or system equipment, be sure to wear a safety helmet to avoid accidentally hitting your head.
When transporting batteries, battery modules and other photovoltaic equipment, pay attention to the force evenly, or carry it with two people to prevent sprains caused by excessive force.
(5) Thermal burns
Under the sunlight of summer, the temperature of the glass surface and aluminum alloy frame of the photovoltaic array will reach above 80°C. To ensure safety and prevent skin burns, be sure to wear protective gloves when operating the photovoltaic system in summer, and try to avoid hot spots.
(6) Electrical damage
Electric shocks can cause burns or shocks, muscle contractions or trauma, and even death. If the current flowing through the human body is greater than 0.02A, it will cause harm to the human body. The higher the voltage, the greater the current flowing through the human body. Therefore, whether it is direct current or alternating current, photovoltaic power or grid power, as long as there is a certain voltage, it will cause damage. Although the output voltage of a single battery module is not very high, the output voltage of a dozen modules connected in series is often higher than the AC voltage output by the inverter. In order to avoid electric shock damage during operation, one is to ensure that the relevant power supply is cut off; the other is to use a clamp ammeter to test the line current as much as possible; the third is to wear insulating gloves.
(7) Chemical hazards
Off-grid photovoltaic power generation systems often use batteries as energy storage systems, and lead-acid batteries are one of the common batteries. Lead-acid batteries use sulfuric acid as the electrolyte, which is highly corrosive and may leak during operation or spray during charging. The skin can be chemically burned if it comes into contact with exposed areas of the body. In addition, the eyes are particularly vulnerable, and the clothes will burn a hole. Although the electrolyte leakage of sealed lead-acid batteries is relatively rare, it is still necessary to be just in case.
In addition, the battery will emit a small amount of hydrogen during the charging process. Hydrogen is a flammable gas. When the hydrogen accumulates to a certain concentration, it is very prone to explosion or fire when it encounters an open flame or electric spark. Therefore, the place where the battery is placed should be well ventilated to avoid the accumulation of flammable gas and avoid injury to personnel caused by explosion or fire accidents.
2. Security protection
The safety protection of the construction site, not only to protect yourself, but also to protect the surrounding partners who are working and operating together. First of all, they must wear protective equipment, and they must also care, remind, and cooperate with each other during work, and each construction worker. We must maintain a certain vigilance and must not be paralyzed. For things that require two people to work together, or work that requires two people to be present, don’t do it alone, and don’t reduce labor costs to save time and money. Safety is the biggest saving.
Commonly used safety protective equipment are helmets, protective glasses, gloves, shoes, seat belts, protective aprons, etc.
The helmet protects the head from being bruised or injured by falling objects.
The protective glasses have two functions, one is to protect the eyes from the stimulation of strong sunlight, and the other is to prevent acid splashing during the installation and maintenance of the battery system.
There are many kinds of gloves, and different work contents should choose different gloves. Wire gloves can be used for installation operations; canvas gloves can be selected for moving metal objects with sharp angles or burrs; rubber acid-resistant gloves can be selected for battery maintenance operations; high-voltage insulating gloves should be selected for electrical testing. Of course, you can also choose high-quality full-function gloves for operation.
The choice of shoes depends on the workplace and environment. If the photovoltaic construction site is a new industrial environment, it is best to wear hard-toed labor protection shoes; if it is a ground or mountain environment, it is best to choose standard work shoes or hiking shoes; if it is on the roof For homework, it is best to choose rubber-soled work shoes.
A protective apron is required when operating the battery.
Seat belts are required for operations on roofs, ladders and other environments