For wires and cables used in electrical equipment, we need to know some details, such as applications, selection requirements, etc. Today I will give my friends a detailed introduction to the applications and classifications of wires and cables used in electrical equipment, as well as selection requirements, etc. .
Application and classification of wires and cables for electrical equipment
Wires and cables for electrical equipment are suitable for fire protection systems with high requirements in power plants, chemical industries, tunnels, stations, high-rise buildings, etc. They are especially suitable for power supply lines for emergency power supplies and indoor fire-fighting equipment, power supply lines from emergency power supplies to signal lights, and emergency power supplies to ventilation. Power supply lines for smoke exhaust equipment, etc.
The rated voltage is low. The operating voltage of these wires and cables is 450/750V and below, with the highest not exceeding 0.6/1kV. The operating voltage of signal and instrument cables is generally 300/500V and below. There are strong electricity and weak electricity. The carrying capacity of the cable is determined according to the usage requirements of the cable. There are various types of insulation materials and sheath materials used in cables, with different performance indicators. Cables are widely used, but they are highly specialized and generally cannot be used universally.
Classification of wires and cables for electrical equipment:
1. Low-voltage distribution wires and cables mainly refer to fixedly laid and mobile power supply wires and cables. Such as general rubber and plastic insulated wires, rubber and plastic insulated flexible wires, shielded insulated wires, rubber sheathed flexible cables, etc.
2. Signal and control cables mainly refer to the wires and cables used to transmit signals or control operations between the control center and the system. Such as control cables composed of various insulating materials and sheaths, control cables for intrinsically safe circuits, low-smoke halogen-free resistance electronic computer control cables, etc.
3. Instrument and equipment connection lines mainly refer to the internal installation lines and external lead lines of instruments and equipment. For example: IE grade K3 instrument installation wiring cables for nuclear power plants, flexible cables for signal and power equipment for water conservancy project observation, flame retardant instrument wires and cables, fluorine insulated computer cables, etc.
4. Transportation wires and cables mainly refer to wires and cables used in supporting automobiles, motorcycles, ships, airplanes, etc. Such as insulated wires for road vehicles, aviation wires, ship cables, rolling stock cables, elevator cables, etc.
5. Geological resource exploration and mining wires and cables mainly refer to wires and cables used for coal, ore, and oil field exploration and mining. Such as: oil platform cables, geological exploration cables, coal mine flame retardant cables, mining wires and cables, etc.
6. DC high-voltage cables mainly refer to wires and cables used in X-ray machines and electrostatic equipment. Such as: photography light source cables, DC high-voltage flexible cables, high-voltage electric furnace cables, high-voltage cables for electron microscopes, etc.
7. Special wires and cables mainly refer to wires and cables that are resistant to high temperatures, fireproof, and used in nuclear power plants. Such as cables, fluoroplastics or silicone rubber used in nuclear power plants.
8. Heating cables mainly refer to wires and cables used for domestic heating, plant cultivation, pipe insulation, etc. Such as: self-controlled temperature heating cable, mineral insulated heating cable, etc.
Requirements for the selection of wires and cables for electrical equipment
1. When selecting, you should fully understand the variety specifications, structure and performance characteristics of wires and cables to ensure product performance and extend service life. Wires and cables for electrical equipment include high temperature resistance, cold resistance, different softness, and shielding properties. They must be selected reasonably according to the conditions of use.
2. The selection of wires and cables should also be considered in conjunction with the use of connectors and the reasonable wiring design of the entire machine. In the wiring design of wires and cables, various external damage and interference factors (mechanical, heat, lightning, electricity) should be avoided as much as possible. and other factors) or take corresponding protective measures. The distance, position difference, fixing method and spacing during laying, the form and performance of connectors, configuration methods, cooperation with other line equipment, etc. must be carefully studied and designed correctly to ensure the safety of wires and cables. Reliable to use.
Basic characteristics of wires and cables for electrical equipment
1. Electrical properties
Conductive properties: resistance of conductive core (DC resistance of wire) and current carrying capacity. Electrical insulation properties: insulation resistance, voltage resistance characteristics, etc.
2, Mechanical properties
Refers to tensile strength, elongation, bending, elasticity, softness, vibration resistance, wear resistance and impact resistance, etc.
3. Thermal performance
Refers to the heat resistance level of the product, operating temperature, heating and heat dissipation characteristics of the cable, current carrying short circuit and overload capacity, thermal deformation and thermal shock resistance of synthetic materials, thermal expansion of materials and dripping performance of impregnated or coating materials, etc.
4. Corrosion and weather resistance
Refers to resistance to galvanic corrosion, resistance to biological and bacterial erosion, resistance to chemicals (oil, acid, alkali, chemical solvents, etc.), salt spray resistance, sunlight resistance, cold resistance, mildew resistance and moisture resistance, etc.
5. Aging performance
It refers to the ability of a product and its constituent materials to maintain its original performance under the action of mechanical (force) stress, electrical stress, thermal stress and various other external factors, or under external climate conditions.
6. Other performance
Including material characteristics (such as hardness, creep of metal materials, compatibility of polymer materials) and certain special use characteristics of the product (such as flame retardancy, etc.)
Through the above content, we have already understood the application and classification of wires and cables for electrical equipment. It can be seen that the applications of wires and cables for electrical equipment are very wide. When choosing, everyone should choose according to the selection requirements.
