What is Mineral-insulated copper-clad cable?

Mineral insulated cables operate continuously at a temperature of 250 ℃ and can sustain power supply for 3 hours at temperatures ranging from 950 ℃ to 1000 ℃. They can work close to the melting point of copper at 1083 ℃ for short or extraordinary periods. Due to the excellent performance of mineral insulated cables, they are suitable for circuits with rated voltages below 1000V.

The use of mineral insulated cables

Mineral insulated cables are commonly used in important electrical engineering fields, such as hazardous areas, important public facilities, personal and property safety areas, and are commonly used in airports, firefighting, high-rise buildings, libraries, shopping malls, hospitals, etc; Mineral insulated cables can be permanently used once installed and laid.

Mineral insulated cables are composed of high conductivity copper conductors, mineral (magnesium oxide) insulation materials, and seamless copper pipe sleeves. When cables are used in situations where copper is corrosive, a layer of anti-corrosion protection outer sheath is added to the outermost layer. Mineral insulated cables have advantages such as fire, waterproof, explosion-proof, non combustible, smokeless, non-toxic, and fire-resistant.

Structure of mineral insulated cables

1. Cable conductor: Made of high conductivity metal copper as the conductor.

2. Insulation layer: High temperature resistant and non combustible inorganic minerals are used as insulation materials.

3. Isolation layer: Made of inorganic mineral materials.

4. Outer protective layer: Made of low smoke non-toxic plastic or metal materials, with good anti-corrosion properties.

The main performance of mineral cables

(1) Fire resistance performance: Due to the fact that mineral cables are all composed of inorganic substances, they will not cause a fire, cannot burn or support combustion, and will not produce toxic gases. Even if there is external flame combustion, the cables can still operate normally. After the fire is cleared, the cable does not need to be replaced. It is a true fireproof cable, providing a foolproof guarantee for the fire line, and has passed the test of International Electrotechnical Commission IEC331.

(2) High current carrying capacity: since the normal operating temperature of Mineral-insulated copper-clad cable can reach 250 ℃. IEC60702 stipulates that the continuous operating temperature of Mineral-insulated copper-clad cable is 105 ℃. This is in consideration of the terminal sealing materials and safety needs. Even so, its cutoff is far more than other cables. Because magnesium oxide powder has a better conductor coefficient than plastic, the same operating temperature, the cutoff is larger. For lines above 16mm, a section can be reduced, For areas that do not allow human contact, two cross-sections can be lowered.

(3) Waterproof, explosion-proof and corrosion resistant: since the cable is sheathed with Low smoke zero halogen high flame retardant material, it has high corrosion resistance (plastic outer sheath is only required in the case of individual chemical corrosion), and the conductor, insulation and sheath are compact and solid. Therefore, it not only has the ability to prevent damage from water, moisture, oil, and some chemical substances, but also can be used in places with explosion hazards and various explosion-proof equipment and equipment connections. Recommended product: Power cable

(4) Overload protection: When the circuit is overloaded, plastic cables may cause insulation heating or breakdown due to overcurrent or overvoltage. For Mineral-insulated copper-clad cable, as long as the heating cannot reach the melting point temperature of copper, the cable will not be damaged. Even if the breakdown occurs instantaneously, the high-temperature magnesium oxide at the breakdown point will not form carbides. After the overload is cleared, the performance of the cable will not change and can still be used normally.