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To calculate a fuse rating, manufacturers work from a simple equation: Power (watts) = Voltage x Current (amps) What we really want to know with this equation is the current (amps). Amps = Watts / Voltage. So, let’s say we need to work out the fuse rating for a washing machine. 850/120 = 7.08 amps.
How do you calculate fuse rating?
The fuse rating can be calculated by dividing the power used by the appliance by the voltage going into the appliance. For the lighting circuit, the fuse current rating should be minimum 2 times the full load current of the total number of lighting.
How do you figure what size fuse you need?
Example: For a 4 AWG single wire outside an engine room, maximum fuse amperage is 150A. B Calculate MINIMUM FUSE AMPERAGE by multiplying product amperage rating by 125%. Minimum fuse amperage provides more protection for the wire but may result in nuisance blows. Example: 80A x 125% = 100A.
What fuse do I need for 240v?
100 Watts divided by 240 Volts equals 0.42 amps +10% which equals 0.46 Amps. So from this calculation the ideal fuse would be 1 amp. However most manufacturers put a 3 amp fuse in the plug as standard.
Do fuses formula?
Fuse Rating = Wattage / Voltage Let us learn here how to calculate fuse rating of any electrical appliance with a neat example.
Can I use a 5 amp fuse instead of a 13 amp?
Yes. The 13amp plug is designed so you set the fuse to the device. So in your case, if the light or radio only needs a 5amp fuse, you use that size.
What are the standard fuse sizes?
Standard sizes for fuses and fixed trip circuit breakers, per 240.6, are 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 125, 150, 175, 200, 225, 250, 300, 350, 400, 450, 500, 600, 700, 800, 1000, 1200, 1600, 2000, 2500, 3000, 4000 5000, and 6000 amps.
What is a 3 amp fuse used for?
Plugs for appliances rated up to about 700 watts should have a 3-amp fuse (coloured red). For example: 3A Fuse – Table lamp, standard lamp, television, video, computer, mixer, blender, fridge, freezer, power drill, jig saw, soldering iron.
Can I use a 250V fuse for 12V?
I have used 250V fuses on 12V circuits without relevant voltage drop (less than 0.5V). But the quality of the fuses may differ. I can confirm that they were working as some of these fuses blew instantly when short circuited. The best way is to measure the voltage before and after the fuse and see if it’s acceptable.
Can I use a 13 amp fuse instead of a 10 amp?
If you replaced it with 13A fuse, it will allow current more than 10A, so it may possible that other components may get damage due excessive current flow than specified. If TV components can sustain up to 13 A current, you can replace it.
Can you put a 3 amp fuse in a 13amp fused switch?
A 3A fuse is the safest to use and should be used for appliances at 700w or less. Appliances rated above 700w should use a 13A fuse. Be extra cautious when using a 13A fuse and try using a 3A fuse if and when it’s possible.
What is current formula?
Current is usually denoted by the symbol I. Ohm’s law relates the current flowing through a conductor to the voltage V and resistance R; that is, V = IR. An alternative statement of Ohm’s law is I = V/R.
Can I use a 3A fuse instead of 5A?
A 3A fuse was used for a reason. If you replace it with a 5A fuse you will lose part of the protection the 3A fuse was intended to provide. In case of a failure of the device the fuse is suppose to protect, the result of using a larger fuse could be to damage the device to the extent that it could not be repaired.
What happens if you use the wrong amp fuse?
Fuses are present to protect the components of the electrical system. Rather than destroying the circuit when there is a surge of power, the fuse blows to protect it. If you use a fuse with the wrong amperage, the fuse won’t blow as intended, damaging the circuit and resulting in a much larger repair bill.
Can you put a 10a fuse in a 5A plug?
Possibly yes. It is possible to short out a circuit by overdrawing more than 5 Amp by removing the 5 Amp fuse and putting in a 10 Amp fuse.
What are the fuse ratings?
The standard voltage ratings used by fuse manufacturers for most small- dimension and midget fuses are 32, 63, 125, 250 and 600.
How is motor fuse rating calculated?
Motor Fuse sizing calculation: In other words, the fuse rating is equal to 1.25 times the full load current. V(V-L) = Line to Line Voltage in volts. For continuous operation, the fuse rating is less than the 125% is not recommended since all the motor is designed to run 120% of the full load rating.
What are the 3 types of fuses?
Different Types of Fuses – Constriction, Working & Characteristics DC Fuses. AC Fuses. Cartridge Fuses. D – Type Cartridge Fuse. HRC (High Rupturing Capacity) Fuse or Link Type Cartridge Fuse. High Voltage Fuses. Automotive, Blade Type & Bolted Type Fuses. SMD Fuses (Surface Mount Fuse), Chip , Radial, and Lead Fuses.
What are 5A fuses used for?
5A Fuse. Used mainly for lighting circuits.
What is a 1 amp fuse used for?
1 AMP Ceramic Fuse are suitable for various different uses. These include providing reliable performance and cost-effective circuit protection. They are ideal for use in plugs to protect cables from melting or catching fire if they are overloaded.
Can I use a 250V fuse in place of 125V?
For example, a 125V fuse can be replaced with a 250V fuse of equal amplitude while the voltage of the application is 250V or lower, but a a 250V fuse can’t be replaced with a 125V fuse of equal amplitude if the voltage of the application exceeds 125V.
What does 250V P mean on a fuse?
250V = Max working voltage. P = RoHS compliant (lead free)Oct 11, 2015.
Can I use 240v fuse for 12V?
240 volts may be the maximum safe voltage rating for it. 15 amps is 15 amps, and it will be quite OK to use with 12 volts.
How many amps is a 250V fuse?
Semiconductor Fuse – 250 Volts The 250 volt semiconductor fuse is a current limiting, very fast-acting, fuse rated to 250 volts AC and up to 250 volts DC. Current ratings range from 1 to 2,500 amps. The maximum interrupting rating, is 200,000 amps AC and 100,000 DC.
