Wiring steps for explosion-proof permanent magnet motor circuits

Explosion-proof permanent magnet motors are mainly used in coal mines, oil and gas, petrochemical and chemical industries. In addition, it is also widely used in textile, metallurgy, city gas, transportation, grain and oil processing, papermaking, medicine and other sectors. As the main power equipment, explosion-proof motors are usually used to drive pumps, fans, compressors and other transmission machinery. We have previously learned about the reasons why explosion-proof permanent magnet motors heat up, so what are the wiring steps for explosion-proof permanent magnet motor lines? Let’s find out together below!

The explosion-proof permanent magnet motor is connected to the power supply using a rubber-covered soft cable. The wiring steps are as follows:

1. Clean the stains on the outside of the junction box and peel off the insulation of the cable.

2. Remove the outlet gland, cable guide sleeve, sealing ring and junction box cover.

3. Put the outlet gland, cable guide sleeve and sealing ring on the cable, then connect the power core wire and ground core wire of the cable to the terminal and screw respectively, and we must also pay attention to the exposed part of the wire not to be exposed on the bow. Type washer outside.

4. After installing the sealing ring, install the cable guide sleeve, outlet pressure plate and junction box cover.

5. During the disassembly and assembly process, attention should be paid to protecting the explosion-proof surface from damage. 204-1 anti-rust oil should be applied during assembly. After installation, the explosion-proof surface must fit tightly.

Explosion-proof permanent magnet motors can be divided into explosion-proof motors, increased safety motors, positive pressure motors, non-sparking motors and dust explosion-proof motors according to the explosion-proof principle.

In a very short period of time, a large amount of energy is released, high temperature is generated, and a large amount of gas is released, causing high-pressure chemical reactions or state changes in the surrounding medium. The rapid release of energy will cause violent impact and damage to surrounding objects.

Three conditions must be met for an explosion-proof motor to explode:

① Explosive substances: substances that can react with oxygen (air), including gases, liquids and solids. (Gas: hydrogen, acetylene, methane, etc.; liquid: alcohol, gasoline; solid: dust, fiber dust, etc.)

② Oxygen: air.

③ Ignition sources: including open flames, electrical sparks, mechanical sparks, electrostatic sparks, high temperatures, chemical reactions, light energy, etc.

The explosion-proof reasons for explosion-proof permanent magnet motors are as follows:

Explosive substances: Many production sites produce certain flammable substances. Explosive substances exist in about two-thirds of underground coal mines; in the chemical industry, explosive substances exist in more than 80% of production workshop areas. Oxygen: Oxygen is everywhere in the air. Ignition source: A large number of electrical instruments are used in the production process. Various friction sparks, mechanical wear sparks, static sparks, high temperatures, etc. are inevitable, especially when instruments and electrical failures occur.

Objectively speaking, many industrial sites meet explosion conditions. When the mixed concentration of explosive substances and oxygen is within the explosion limit range, if an explosion source exists, an explosion will occur. Therefore, it is very necessary to take explosion-proof measures.