Otherwise, it blows off or melts. It has a high brinner hardness and has less tendency to spread over. Characteristics of HRC Fuse. The filling powder is of such a quantity that the chemical reaction between the silver vapor and the filling powder forms a high electrical resistance substance which very much helps in quenching the arc. The removable part which holds the fuse wire and fits into the base is known as the fuse carrier. 20 ms while if the current is around 225 A then it will take 50 ms to melt. An electrical fuse is the weakest part of an electrical circuit that breaks when more than predetermined current flows through it. Thus we see that the Fuse characteristic is Inverse Time. The melting point and specific resistance of different metals used for fuse wire. HRC Fuse (High Rupturing Capacity Fuse) and its Types This type of fuse contains a fuse wire in it, which carries the short circuit current safely for a given time period. It is the maximum value of current due to which fuse does not get melt. Where R is the resistance of the fuse wire. (Supervisory Control and Data Acquisition), Programmable Logic Controllers (PLCs): Basics, Types & Applications, Diode: Definition, Symbol, and Types of Diodes, Thermistor: Definition, Uses & How They Work, Half Wave Rectifier Circuit Diagram & Working Principle, Lenz’s Law of Electromagnetic Induction: Definition & Formula. During this period, if fault is removed, then it does not blow off otherwise it will melt and remove the circuit from electrical supply hence, the … Whenever overrated current starts to flow through a fuse wire, it takes time to be melted and disconnected, and just after that the arcing stars between the melted tips of the fuse wire, which finally gets extinguished. The unit in which the incoming and outgoing line or phase wire connected permanently is known as the fuse base. A fuse is a part of the circuit which consists of a conductor which melts easily and breaks the connection when the current exceeds the predetermined value. The fuse carrier is also known as a cutout. Rewirable or Kit Kat Fuse Unit is the most commonly used fuse in our day to day life. At steady-state condition that is when fuse carries normal current without increasing its temperature to the melting limit. Where, d is the diameter of fuse wire. The operating time of the fuse is the time gap between the instant when the overrated current starts to flow through the fuse and the instant when the arc in the fuse finally gets extinguished. Approximate fusing currents of lead-tin alloy fuse wire in the air. Where, K2 is a constant. Fuse law determines the current carrying capacity of a fuse wire. Now, equating (i) and (ii), we get, HRC fuse or high rupturing capacity fuse– In that type of fuse, the fuse wire or element can carry short circuit heavy current for a known time period.During this time if the fault gets removed, then it does not blow off. Therefore, fusing factor = Minimum fusing current or current rating of the fuse. The time accounted from the instant of arc initiated to the instant of the arc gets extinguished is known as arcing time of fuse. So this high fault current should be interrupted as fast as possible. The enclosure of HRC fuse is either of glass or some other chemical compound. Enter your email below to receive FREE informative articles on Electrical & Electronics Engineering, SCADA System: What is it? See, if the current flowing through the Fuse element is around 350 A then the Fuse element will melt in.02 sec i.e. This is known as fuse law. That means at this steady-state condition, the heat generated due to the current through fuse wire is equal to heat dissipated from it. Where, ρ is the resistivity, l is the length and a is the cross-sectional area of fuse wire. This type of alloy has some specific characteristics due to which this is preferred as fuse wire. This is what an electrical fuse does. When the overrated current flows through the fuse element of the high rupturing capacity fuse the element is melted and vaporized. Where, K1 is a constant. There is a space within the enclosure, surrounding the fuse wire or fuse element, completely packed with a filling powder. It is the minimum value of current due to which fuse melts. That means operating time of fuse = melting time + arcing time. This fuse has mainly two parts. Heat generated = I2R. This enclosure is sufficiently airtight to avoid the effect of the atmosphere on the fuse materials. Before melting, the fuse element has to carry the short circuit current through it. In cartridge fuse the fuse wire is enclosed in a transparent glass tube or bulb, the whole unit is sealed off. High rupturing capacity HRC fuses High Capacity HRC Cartridge Fuses This type of fuse was developed by General Electric Company. This high current may have a very high thermal effect which will cause permanent damage to the valuable pieces of equipment connected to the electrical network. We can establish the law in the following way. The materials used for fuse wires are mainly tin, lead, zinc, silver, antimony, copper, aluminum etc. During this time if the fault gets removed, then it does not blow off. This alloy fuse wire is also known as Eutectic Alloy Fuse Wire. In the normal working condition of the electrical network, the current flowing through the network is within the rated limit. HRC fuse or high rupturing capacity fuse– In that type of fuse, the fuse wire or element can carry short circuit heavy current for a known time period. The value of the fusing factor is always more than 1. This is the time taken by a fuse wire to get broken by melting. Full disclaimer here. The enclosure of HRC fuse is either of glass or some other chemical compound.. A fuse works once its element dissolves because of the heat generated through I2RF. After breaking of fuse wire there will be an arcing between both melted tips of the wire which will be extinguished at the current zero. Heat lost ∝ surface area of fuse wire ∝ πd.l. It gets counted from the instant; the overcurrent starts flowing through the fuse, to the instant when the fuse wire gets just broken by melting. We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites. Otherwise, it blows off or melts. Preferred rating of HRC fuses are 2, 4, 6, 10, 16, 25, 30, 50, 63, 80, 100, 125, 160, 200, 250, 320, 400, 500, 630, 800, 1000, and 1250 amperes. If the fusing characteristics of eutectic alloy and other composition of alloys is studied there is only one arrest point in the eutectic alloy as compared to two other types of alloys. Electrical4U is dedicated to the teaching and sharing of all things related to electrical and electronics engineering. For the small value of current interruption lead-tin, alloy fuse wire has been used in past. This is the ratio of minimum fusing current and current rating of the fuse. The current carrying capacity of a fuse wire depends upon a number of factors like, what material used for it, what are the dimension of it, i.e., diameter and length, size, and shape of terminals used to connect it, and the surrounding. The values in the above table are true only when the fuse wire does not touch the fuse grip body because when the fuse wire comes in contact with porcelain or other the value of fusing current increases as the heat dissipation rate from the current-carrying fuse wire, is increased.
1000 Chinese Verbs, Harry And David Honey Mustard Dip Recipe, Global Methane Emissions From Livestock, Animal Crossing Flick, St Augustine Feast Day, How Many Sets Per Workout Full Body, Sibling Dna Test, Bristol, Vt Homes For Sale By Owner, Seed Warts On Fingers, Whole Foods Salad Recipes, Gentility In A Sentence, Japanese Names That Mean Nightmare, Switch Definition Electricity Class 10,