Learn more about Low Voltage Fuses
Learn more about Low Voltage Fuses
A fuse is a type of over-current protective device that is designed to be a sacrificial element in an electrical power system. Fuses are designed to open circuits when excessive over-currents are present and are designed to prevent further damage to the system that might result if the fuse were not present. The use of fuses in a circuit provides cheap insurance should there be an accidental or unintentional fault in the system wiring or components. Low voltage fuses are very common in electrical systems and they come in diverse styles, shapes and sizes. Low voltage fuses are defined as fuses with a voltage rating less than or equal to 1,500V.
What are the main groups of low voltage fuses?
Several fuse systems, showing different shapes, contact styles, technologies, etc. have historically developed in different countries. There are many thousands of different low voltage fuses that exist in the world, however most of them belong to one of the following groups:
Miniature fuses
Miniature fuse are relatively small in physical size and extremely diverse in application. The most common sizes are the 5 x 20mm (M205) and the 6.3 x 32mm (3AG) fuses, which account for the greatest volume sales of this group. Originally designed for automotive applications, today they are used in electronics, instrumentation, audio, power supply protection and thousands of different applications. They are still the largest group of fuses sold in the world by volume.
Cartridge fuses
Cartridge fuses are very popular around the world, making this group a diverse range of fuses & represented by almost every brand. The three most popular sizes for industrial applications are 10 x 38mm, 14 x 51mm and 22 x 58mm and a great range of DIN Rail mountable fuse holders are available for them. For Australian service fuse applications, the 22 x 58mm and 30 x 57mm are very popular and for multimeter applications, a large range of European & American midget fuses is available.
British Standard fuses
Industrial fuses made to BS88 standards are very popular in countries like England, Australia and South Africa. The industrial versions are characterised by either clip-in tags, offset tags or centre tags. To install them in their holders, the usual practice is to screw the fuse to the inside of the fuse holder wedge which then slides into the holder base. British standards (eg. BS1361) also cover service fuses and J-Type fuses.
British Standard Ultra Rapid fuses
Industrial fuses made to BS88 standards are very popular in countries like England, Australia and South Africa. The industrial versions are characterised by either clip-in tags, offset tags or centre tags. To install them in their holders, the usual practice is to screw the fuse to the inside of the fuse holder wedge which then slides into the holder base. British standards (eg. BS1361) also cover service fuses and J-Type fuses.
DIN NH Blade fuses
The DIN NH Blade fuse is sometimes referred to as the 'Eurofuse' because of its popularity in Europe but in fact, this style of fuse is also very popular in China, India, the Middle East, Australia and Africa. It features two lugs attached to the fuse plates which act as a facility for a special 'fuse-puller' tool, two solid tags commonly known as blades and a blown fuse indicator on its top plate. DIN NH fuses are popular due to their low price, availability, blown fuse indicator function and the speed with which a blown fuse can be replaced.
European Standard Semiconductor fuses
There are many varieties of European DIN Standard Ultra Rapid (Semiconductor) fuses that have been manufactured over the years. Some of them were 'limited production run' versions and some of them were 'specials' made by only one brand. The most commonly used styles are the DIN00-80, the Square Body style and the DIN blade style. They are known for their high breaking capacities and their compact sizes and are among the world most advanced designs.
American Standard fuses
American Standard fuses are used in electrical systems in the USA, Canada and South America. In Australia & NZ, they are predominantly sourced as replacement parts for imported American equipment. They are manufactured to UL and CSA standards and are classified according to the following classes: T, J, L, RK5 & RK1.
PV fuses
Photovoltaic, or 'PV' as it is also known, refers to the technology that converts light directly into electricity. Electrical systems that convert the sun's energy into electricity are very reliable as long as they are protected properly. Any solar installation is vulnerable to fault currents or lightning strikes. Today, fuses and surge arrestors are the most effective ways of protecting the wiring and all the electrical equipment in a photovoltaic system. The unique and specific nature of this protection has resulted in the creation of a whole new category of fuse products, known as Photovoltaic (PV) fuses.
Bottle fuses
Bottle fuses, or 'D' fuses are mainly used for domestic applications in Europe as well as some industrial applications. They derive their name from their unique bottle shape and have a colour coded indicator system at one end cap.
Automotive & DC fuses
The world of automotive fuses is expansive. In years gone by, the glass 3AG fuse was widely used in automotive applications but that was eventually replaced with the 6AC and then the legendary ATO blade fuse which is still being used today. In recent years there has been a proliferation of new auto fuse designs and designers have many options. DC fuses are used in forklift and electric lift truck applications but are now also considered to be convenient solutions for other DC circuits.
Marine fuses
SIBA have created a range of fuses specifically for marine applications. The range consists of a 5x25mm cylindrical fuse, bottle shape fuses and ISOMET NH blade fuses along with specialist fuse holders and accessories. They conform to the demanding IEC60269-2-1, VDE0636 and are engineered to the highest quality possible. They are part of the NATO stock number program and frequently used in military applications.
Mining fuses
SIBA have created a range of fuses specifically to meet the stringent demands of mining applications. These fuses are available in various forms including bottle shape, NH Blade shape and cylindrical shape and all conform to the IEC utilization category gB. Designed for 'sparkless' operation, this fuse range is the ultimate fusing system available for demanding mining applications.
Accessories
Many accessories are available for fuse applications including an assortment of fuse pullers, fuse testers and passive voltage indicators. In addition, a large range of fuse theory books, field application manuals and white papers are also available.
Sub-miniature and SMD fuses
Sub-miniature fuses are designed to primarily protect circuits from over-currents that are in a printed circuit board (PCB) environment. They are physically small so that they do not take up a lot of valuable space on the PCB and they are available in either 'through-hole' technology or 'Surface Mount Device' (SMD) technology. Through-hole technology means that the fuse has leads that are soldered to the PCB or the fuse sits in a holder that is soldered on to a PCB. SMD means that the fuse is placed onto a PCB via special adhesive. SMD fuses are the smallest fuses in the world and they often use a conductive film as the element.