Comparison table of fuse & How to choose the specifications of fuse

Glass tube fuse is a type of fuse that mainly protects the entire circuit board and circuit safety by fusing its own fuse when there is an abnormal increase in current, temperature, voltage resistance, etc.

Today, let’s lean about Comparison table of fuse & How to choose the specifications of fuse.

One、 Comparison table of fuse model specifications

Common fuse specifications: (lead not less than 98%, antimony 0.3-1.5%, impurities not more than 1.5%) diameter (mm) rated current (A) rated power (W) fuse current (A) fuse power (W), mainly including rated current, rated power, and fuse power.



Rated current(A) Fusing current(A) Diameter


Rated current(A) Fusing current(A)
0.28 1 2 0.81 3.75 7.5
0.32 1.1 2.2 0.98 5 10
0.35 1.25 2.5 1.02 6 12
0.36 1.35 2.7 1.25 7.5 15
0.4 1.5 3 1.51 10 20
0.46 1.85 3.7 1.67 11 22
0.52 2 4 .75 12.5 25
0.54 2.25 4.5 1.98 15 30
0.6 2.5 5 2.4 20 40
0.71 3 6 2.78 25 50


Rated current(A) Fusing current(A) Diameter


Rated current(A) Fusing current(A)
0.508 2 3.0 1.63 11 16.0
0.559 2.3 3.5 1.83 13 19.0
0.61 2.6 4.0 2.03 15 22.0
0.71 3.3 5.0 2.34 18 27.0
0.813 4.1 6.0 2.65 22 32.0
0.915 4.8 7.0 2.95 26 37.0
1.22 7 10.0 3.26 30 44.0

Two、How to choose the specifications of fuse

  1. Safety certification: The safety certification of the fuse must be determined based on the safety certification required for the entire machine, such as UL or IEC specifications.
  2. Structural dimensions: It is necessary to determine its size based on the space designed in the circuit, such as length, diameter, and whether it has leads.
  3. Rated voltage: must be greater than or equal to the actual application voltage, generally including 24V, 32V, 63V, 125V, 250V, etc.
  4. Breaking capacity: should be greater than the maximum fault current in the circuit.
  5. Rated current: determined based on the following:fuse(1) Normal working current, operating at 25 ° C, rated current of UL specification fuse ≥ normal working current/0.75; The rated current of IEC specification fuses is 2 positive

    Normal working current/0.9.

    (2) Environmental temperature: The current carrying capacity test of the fuse is carried out under the condition of an environmental temperature of 25 ° C. The higher the environmental temperature, the shorter the lifespan of the fuse and its carrying capacity

    The lower the ability, so when choosing a fuse, environmental temperature should be considered.

    (3) Pulse: Pulse generates thermal cycling and mechanical fatigue that affects the lifespan of the fuse. When designing, pulse I2T should be kept small while considering the pulse factor

    The nominal melting heat energy of the fuse is l2T, and the rated value of the fuse | I2T>the actual pulse I2T/Pf Pf: Pulse factor, which varies depending on the number of pulses it can withstand.

    Quick Blow Glass Tube Fuse Assorted Kit FBGTF1033

  6. Testing: The sample selected through the above procedure needs to be tested in the actual circuit to verify whether the selected fuse is suitable. This verification should include positive

    Testing under normal and fault conditions to ensure that the selected fuse plays a protective role in the protected circuit.

    Three、 Precautions for selecting fuses

    1. Do not use too thin fuses. Using thin fuses can easily cause normal current to burn out, resulting in unnecessary power outages. You can’t choose too thick either

    Fuses with excessive current are not easily blown, but they can also easily lead to fires.

    1. It is necessary to choose and use appropriate fuses, and the melting current of the fuse is usually 1.5-2.0 times the rated current. The total power of each household appliance during normal electricity consumption

    If the sum of the rates exceeds 1100 watts, choose a 5-ampere fuse and use a No. 20 fuse with a diameter of 098 millimeters. When the current exceeds 7.5 amperes to 10 amperes, ensure that

    The fuse will automatically fuse to achieve the purpose of protection.

    1. If the selected and used fuse meets the specifications and frequently experiences fuse melting, it indicates that there is a problem with the electrical circuit and equipment, and an electrician should be consulted in a timely manner

    Identify the cause and eliminate potential hazards. Do not replace coarse fuses or simply replace them with copper wire, iron wire, etc. at will.

    FBELE is a professional fuse manufacturer in China, equipped with a complete set of production and manufacturing equipment and testing instruments, with excellent product performance and long service life; Complies with the RoHs directive of the European Union and has passed quality system certification and safety compliance certification

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