Surge protective devices (SPDs) are often backed by fuses and small circuit breakers or molded-case circuit breakers. When these elements are coordinated with SPDs, they should remain unaffected during rated surge current conditions, ensuring the normal dissipation of surge current while maintaining a residual voltage (Ur) on branch circuits below the protection level of the electrical equipment (Up). … Read more
Photovoltaic power plants, closely connected to the lives and production of people, are raising high concerns across the industry regarding how to ensure the “safety” of photovoltaic power stations, especially in the case of retrofit distributed photovoltaic systems installed on building rooftops. Countries worldwide have made related regulations concerning the DC-side voltage, DC arc protection, … Read more
Modular Contactors are divided into AC contactors (voltage AC) and DC contactors (voltage DC), and they are used in power generation, distribution, and utilization scenarios. In a broad sense, contactors refer to electrical devices used in industrial electricity, where a coil carries current to create a magnetic field, closing the contacts to control electrical loads. Before installing AC … Read more
Introduction In the rapidly evolving world of solar energy, ensuring the safety and efficiency of your solar power system is paramount. A critical component in achieving this is the Solar (PV) DC Miniature Circuit Breaker (MCB) with an enclosure box. This article guides you through the straightforward installation process of this essential element, particularly vital for systems … Read more
As a protective component in the DC side configuration of photovoltaic power stations, the design of DC fuses varies across different schemes. This article first describes the protective principle and application scenarios of fuses, combined with the technical requirements of various standards, and proposes parameter configuration requirements for photovoltaic DC fuses. It then discusses the issues and … Read more
Basic Composition of Household Photovoltaic Distribution BoxesTypically, the household distribution box consists of a knife switch, a self-resetting over and under voltage protector, circuit breakers, surge protectors, and backup circuit breakers for surge protectors. Circuit BreakersCircuit breakers (air switches, miniature circuit breakers) mainly provide overload and short circuit protection in circuits, and are also used … Read more
Fuses are active components primarily used for overload and short circuit protection in low-voltage distribution networks and control circuits. They can also be used for overload protection of cable conductors and protection of power electronic components. A fuse consists of a fuse base and a fuse (fuse element). When a fuse wire is connected in … Read more
Since photovoltaic combiner boxesare installed in outdoor environments, it is necessary to consider lightning protection for these boxes. For this purpose, a photovoltaic DC-specific lightning surge protector (i.e., lightning arrester) is paralleled at the DC output part of the combiner box. The combiner box is a complete installation in the photovoltaic power generation system that ensures … Read more
A circuit breaker, including high voltage and low voltage types, is an electrical protection device available in various forms, all featuring arc extinguishing devices. The air break switch, officially known as an air-type low voltage circuit breaker, is a specific type of circuit breaker mainly used in low voltage circuits. It utilizes air as the medium … Read more
Low Voltage Circuit Breakers Low voltage circuit breakers, also known as automatic switches, are electrical devices that serve as manual switches and can automatically provide under-voltage, over-voltage, overload, and short-circuit protection. They are used for distributing electrical energy, infrequently starting asynchronous motors, and protecting power lines and motors. In cases of severe overload, short circuit, … Read more