company news about Composition of arc generated in fuse

        The arc is mainly composed of arc column area, cathode area and anode area:

1. The arc column region is electrically neutral. It is composed of molecules, atoms, excited atoms, positive ions, negative ions and electrons. The positively charged ions are almost equal to the negatively charged ions, so it is also called plasma. Charged particles move in the direction of the plasma and basically do not consume energy, so they can transmit large current under low voltage conditions. The main charged particles that transmit current are electrons, accounting for 99.9% of the total number of charged particles, and the rest are positive ions. Because the length of cathode area and anode area is very short, the length of arc column area can be considered as arc length. The electric field intensity in the arc column area is low, usually only 5-10V/cm.

2. The cathode is considered as the source of electrons. It provides 99.9% of charged particles (electrons) to the arc column. The ability of the cathode to emit electrons has a great impact on the stability of the arc. The length of the cathode area is 10-5~10-6cm. If the cathode voltage drop is 10V, the electric field intensity of the cathode area is 106~107V/cm.

3. The anode area mainly accepts electrons, but 0.1% of charged particles (positive ions) should also be provided to the arc column. Generally, the length of the anode area is 10-2~10-3cm, and the electric field intensity of the anode area is 103~104V/cm. Because the anode material and welding current have great influence on the voltage drop in the anode area, it can vary from 0 to 10 V. For example, when the current density is high and the anode temperature is high, so that the anode material evaporates, the anode voltage drop will decrease, even to 0V.