One common misconception about choosing the correct fuse size is that it depends on the load of the circuit. Any wire size or circuit protection recommended by this calculator should be reviewed for adequacy, before installation, by a professional applying the applicable industry standards. Related Post: Difference between Circuit Breaker and Isolator / Disconnector Circuit Breaker Size Calculation for Continuous & Non-contentious Load. Only calculate fuse size yourself when there is no recommended fuse size, and even then only if you possess the appropriate working knowledge and understanding of electrical systems. Additionally, knowing fuse classes are critical for circuit protection in your home as manufacturers set standards to each specific class. This calculator is based on industry standards including NFPA 70, National Electrical Code (NEC). For a household circuit, a 15-amp fuse should be used in this circuit. You consult your inverter’s documentation but don’t find a recommended fuse size. We do not recommend using it for other types of electrical systems. Note: Always use the fuse sizes recommended by the manufacturer when available. Say the calculated fuse rating is 2.2679 amps, use a 3 amp fuse. Fuse rating = (watts/volts) x 1.25 . Things can get ugly fast! Let’s say you’re designing a solar power system and you want to place a fuse between your inverter and battery bank. All Rights Reserved. Fuse Factory expressly disclaims responsibility for any use of this calculator that results in inadequate wire size or circuit protection. These calculators can not account for all possible circumstances, factors or variables pertinent to the selection of an appropriate wire and circuit protecting fuse. The user is further cautioned that the results generated are based upon certain simplifying assumptions, which may or may not be valid for a specific case. The final decision should be made after a review of appropriate standards and guidelines related to your application. Fill out our calculator at the top of the page and it will provide a recommended fuse size based on your inputs. Unfortunately we do not offer them in low amp values at the moment. There are two ways to choose a fuse size: Let’s look at an example for each scenario. Calculate Size of Circuit Breaker or Fuse on Primary and Secondary side of Transformer having following Detail Transformer Details(P)= 1000KVA Primary Voltage (Vp)= 11000 Volt Secondary Voltage (Vs)= 430 Volt Transformer Impedance= 5% Transformer Connection = Delta / Star Transformer is in unsupervised condition. This calculator is a tool to assist people of all skill levels to quickly perform calculations and eliminate unsuitable options. This is almost always in regards to the main power fuse. All electrical systems present a risk of fire and other hazards. Say the calculated fuse rating is 4.9431 amps, use a 5 amp fuse. Calculate Size of Contactor, Fuse, C.B, O/L of DOL Starter Calculate Size of each Part of DOL starter for The System Voltage 415V ,5HP Three Phase House hold Application Induction Motor ,Code A, Motor efficiency 80%,Motor RPM 750 ,Power Factor 0.8 , Overload Relay of Starter is Put before Motor. Your email address will not be published. 4. Read horizontally to the right until the distance is as great or greater than your installation distance. Presets (hexadecimal representation of the fuse settings) can be reviewed and even be set in the last form at the bottom of this page. This fuse calculator makes the following simplifying assumptions: Note: This calculator is designed for solar power systems. Identify the smallest gauge wire the load current will flow through. A common car audio question I get is, "What size should my fuse be?". This calculator may contain errors of entry or calculation. The size of this fuse is dependent on how many solar panels you have and how they are connected (series, parallel, or series/parallel). To choose the right fuse size in this example, simply look for the manufacturer’s recommended fuse size in the charge controller’s documentation. In the case of a 110-volt circuit, using 1200 watts, the calculation would be: 1200/110=10.9 amps. You consult your inverter’s documentation but don’t find a recommended fuse size. Fuses ratings are accurate for operation at 25 Degrees Celsius, When subjected to hotter or colder environments the fuse material will blow at a difference temperature. When outside this range It is important to also take this into consideration for your wiring choices particularly when temperature are hot. Any wire size or circuit protection recommended by this calculator should be reviewed for adequacy, before installation, by a professional applying the applicable industry standards. Fuse rating Calculation: Let we calculate the fuse sizing for 5.5kW 415V three-phase induction … Cheers. Fuse rating = (watts/volts) x 1.25 . ©2018 WWW.FUSEFACTORY.COM.AU RIGHTS RESERVED. Let’s say you’re designing a solar power system and you want to place a fuse between your solar charge controller and battery bank. Identify the load current in the circuit.