What are electrical hazards?

An electrical hazard can be defined as a dangerous condition where a worker could make electrical contact with energized equipment or a conductor, and from which the person may sustain an injury. Under such a case, human body is exposed to a voltage, it acts as a resistor and allows current to pass through it. The value of resistance varies with the physical condition of the human body. Some of the common electrical hazards are: Overhead power lines Damaged tools and equipment Inadequate wiring and overloaded circuits Exposed electrical parts Improper grounding Damaged insulation Wet conditions Preventive measures Electric sparks, loose connection, improper wiring and lack of personal protective equipment can lead to a fire / shock therefore certain precaution should be taken while dealing with an electrical circuit / equipment. Use insulated tools (e.g., spanners) Put covers over the battery terminals Install fuse (e.g., near the battery) Check contact and voltage drop Tighten up screw wherever applicable Check cable and terminal block periodically Always check the voltage between any conductor and any other wires, and to ground Always wear gloves and avoid touching conductive parts (e.g., battery terminals, metal and mounting frames) with bare hands     The post ID for this chapter is 2720. For any suggestion or comment regarding the content, you may write to us at faqs[dot]solar[at]gmail[dot]com. Please quote the post ID in the subject, for better assistance.

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What are chemical hazards?

A chemical hazard is a type of occupational hazard caused by exposure to chemicals in the workplace. Chemical hazards and toxic substances pose a wide range of health hazards such as irritation, sensitization and burns. In order to ensure chemical safety in the workplace, information about the identities and hazards of the chemicals must be available and understandable to workers. Some commonly used workplace chemical hazards include: acids caustic substances cleaning products such as toilet cleaners, disinfectants, mildew remover and chlorine bleach heavy metals, including mercury, lead, cadmium, and aluminium paint pesticides petroleum products solvents photocopier toner, etc. Example: The most common example is the lead-acid batteries which are very common and are also installed in off grid or hybrid solar power plants. Batteries are safe, but caution is necessary when touching damaged cells and when handling lead-acid systems that have access to lead and sulfuric acid. The sulfuric acid in a lead-acid battery is highly corrosive and is more harmful than acids used in most other battery systems. It can cause serious burns and if comes in contact with the eye can cause permanent blindness. Prevention when installing a lead-acid battery: install battery in well-ventilated area keep flames and equipment that create spark away from the battery cover the battery terminal make sure connections are tight and secure use personal protective equipment as per safety regulations.   The post ID for this chapter is 2723. For any suggestion or comment regarding the content, you may write to us at faqs[dot]solar[at]gmail[dot]com. Please quote the post ID in the […]

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What is anti-islanding protection?

Anti-islanding protection is a way for the grid-connected solar inverter to sense when there is a problem with the utility grid, such as a power outage, and shut itself down to stop feeding solar power to the grid. Anti-islanding protection is a mandatory required safety feature that is built into all grid-tied and hybrid inverters that operate in India and various other counties across the globe including US, Germany, etc. This protection feature is required because in case of power failure or outage the utility needs the power lines to be completely safe for maintenance. Some of the regulatory requirements in India for anti-islanding are as follows: according to IEEE 1547 and  Central Electricity Authority of India (technical standards for connectivity of the distributed generation resources) Regulation 2013 – for an unintentional island the grid-tied inverter shall detect the island and cease to energize within two seconds of the formation of an island. according to IEEE 1547 the grid-connected rooftop solar system shall include an adjustable delay (or a fixed delay of five minutes) that may delay reconnection for up to five minutes after the grid voltage and frequency is restored. As per Central Electricity Authority of India Regulation, 2013 the delay shall be for at least 60 seconds.   The post ID for this chapter is 2741. For any suggestion or comment regarding the content, you may write to us at faqs[dot]solar[at]gmail[dot]com. Please quote the post ID in the subject, for better assistance.

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What is an electrical earthing protection?

Earthing is the method of transmitting instant electricity discharge directly to the ground through low resistance wires or electrical cables. It is basically a system designed to protect electrical wires and components from damage caused by sudden electrical power surges. Earthing systems also prevent personnel from electrical shocks in the event of a short circuit. Regardless of system voltage, earthing is required on all solar PV power plants. Its main purpose is to reduce the risk of dangerous electrical shocks to the installer or the user from uninsulated metal parts of a plant. There are two common types of earthing done in solar PV power plants: Equipment earthing – The basic objective of equipment earthing is human safety by preventing the surge of current to an unsafe level. In this metallic body of equipment / devices is connected to the grounding grid to prevent electric shocks to any personnel touching that equipment or device. System earthing – The system earthing is also referred to as neutral earthing. Under this, neutral of the electrical system is directly connected to the earth. Earthing in a solar PV power plant  A rooftop solar power plant earthing is usually divided into two parts based on its electrical construction, AC side and DC side. DC Earthing – These parts cover the equipment in the DC side of the electrical circuit, such as PV modules, module mounting structures, DC junction box, DC Monitoring Box (if any), etc. AC Earthing – These parts cover the equipment in […]

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What are personal protective equipment?

03/01 Personal protective equipment, commonly referred to as “PPE”, is the equipment worn to minimize exposure to hazards that cause serious workplace injuries and infection. The hazards addressed by protective equipment include physical, electrical, heat, chemicals, biohazards, and airborne particulate matter. PPE is the last line of defence in protecting workers from hazards in the workplace. Before requiring workers to wear PPE to protect them from a specific hazard, the employer must try to eliminate the hazard or reduce it as much as possible. PPE is not the most effective safety measure because it places only a barrier between the worker and the hazard. The hazard still exists; so if the right PPE is not worn properly or when it is needed, or the PPE fails (for example, gloves leak), the worker is not protected. Types of Personal protective equipment Head Protection  Head protection is an essential element in providing workers with protection from heavy impact, falling and low-hanging objects, and electrical hazards. A hard hat should be worn in all situations where there are head protection hazards. All forms of head and scalp protection must be of the suitable head size and correct fit. It should have some ventilation and an easily adjustable headband/chin strap, where appropriate. Class G and H hats protects from electrical shocks up to 2,200 volts and 20,000 volts, respectively.The relevant standards are BS EN 397 and BS EN14052. Proper use and care of the hard hat Always wear your hard hat while you are working […]

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How to identify and assess workplace hazards?

A key step in any safety protocol is to conduct a thorough hazard assessment of the work environment and equipment at a workplace. In a hazard assessment, it is important to be as thorough as possible because after all, you can’t protect your workers against hazards you are unaware of. Therefore, there should be a nominated trained safety officer for conducting formal risk assessments at each workplace or project site. To identify and assess hazards, safety officers or trained employers and workers should: collect and review information about the hazards present or likely to be present in the workplace. conduct initial and periodic workplace inspections of the workplace to identify new or recurring hazards. investigate past illnesses, incidents, and close calls / near misses to determine the underlying hazards, their causes, and safety and health programme shortcomings. group similar incidents and identify trends in injuries, illnesses, and hazards reported. consider hazards associated with emergency or non-routine situations. determine the severity and likelihood of incidents that could result for each hazard identified, and use this information to prioritize corrective actions. You can understand the steps necessary to assess your workplace safety hazards for self-assessment here. [LINK to the document/template can be added after checking with trainers/GERMI]. One can also study the ‘Recommended Practices for Safety and Health Programs’ issued by the Occupational Safety and Health Administration, United States.     The post ID for this chapter is 2688. For any suggestion or comment regarding the content, you may write to us […]

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About Phase-II of Grid Connected Rooftop Solar Programme

Ministry of New and Renewable Energy (MNRE), Government of India has launched the Phase-II of Grid Connected Rooftop Solar Programme that provides a subsidy for installing rooftop solar systems. The programme is being implemented through electricity distribution companies and provides a subsidy for the household owner and Group Housing Societies to set up solar systems on the rooftop of their residence/residential campus. 40% subsidy will be provided for installing a rooftop solar system of up to 3kW capacity; 20% subsidy is available for installing a rooftop solar system beyond 3kW and up to 10kW capacity; 20% subsidy will be provided for Group Housing Societies/Residential Welfare Associations for installations up to 500 kW (at 10 kW per house) for common facilities. Click Here to study the Operational Guidelines on implementation of Phase – II of Grid Connected Rooftop Solar Programme. Note: Subsidy benefit from MNRE is available for the residential sector only.        

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When should you install a rooftop solar system?

Though installing a solar PV system has multiple advantages, the installation is a comparatively large investment to make. Thus prior to approaching any installer, it is crucial that the consumer should check if it fulfills the following prerequisites: Roof rights: As the solar PV system would preferably continue to generate electricity for 20-25 years, the consumer has to check if she/he has the right to use the rooftops for installing the solar PV system. Location: The performance of the solar PV system would depend on the amount of direct sunlight the system receives. Thus the consumer has to check if the nearby buildings/ trees do not cast any major shadows throughout the day. How long are you are going to live in your house? Though you will see an immediate reduction in your electricity bill after installing a PV system, however, it will take 4-5 years to recover the initial capital invested. Thus you may install a PV system if you plan to stay in the same house for the long term. Type of roof: This is an important aspect to consider before installing a PV system. The solar panels can be installed on almost each and every rooftop. However, the type of roof may have an effect on the effort and the cost of the structure. If you happen to use terracotta shingles, you may need to find the installer who is experienced and skilled enough to work with such types of rooftops. Did you check the above preconditions […]

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What to check in the proposal provided by the Installer.

Before selecting the installer for setting up a solar PV system, it is important to check the following from the proposals submitted by the installer. Minimum generation guarantee: The solar PV system generates electricity and must be warranted by a minimum generation guarantee. The minimum generation depends on a number of factors including the location, design orientation etc. and should be provided by the installer during feasibility analysis. The consumer should compare the minimum generation guarantee and the compensation rate offered by the installer.   

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What is shadow analysis and why is it important for solar PV installation?

A shadow falling on a solar PV module blocks the flow of solar energy and eventually, the modules generate hotspots/gets damaged through rise in temperature. The shadow could be on the nearby trees, buildings or even the PV module array installed ahead. The efficiency of a PV module at any time reduces in direct proportion to the area of the shadowed part of the module, therefore it becomes highly important to conduct shadow analysis during the feasibility study and designing a rooftop solar power plant. The shading experienced in solar PV plants can be identified as follows: Self-shading- the shadow that occurs on a PV module due to another PV module. Shading due to near objects – the shadow that occurs due to nearby objects which may be present within the vicinity or rooftop, around the installed PV modules. Some of these may affect the plant for a certain time of the day or for the entire day depending on their location, height, distance from the solar module. The shadow that may occur due to far away obstructions like newly built highrise buildings, towers etc. that may cast shadows on the solar power plant. Such situations are rare and at times unpredictable for the future. Identifying a PV array location When designing a solar system there is often the need to understand how long a shadow will be so that row spacing between solar PV modules can be properly designed. Keeping in mind that the sun travels in an arch […]

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