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Anonymous users2024-02-15Copper cable model selection:
First, the choice of cable model.
When selecting cables, it is necessary to consider the use, laying conditions and safety;
According to different uses, power cables, overhead insulated cables, control cables, etc. can be selected;
According to the different laying conditions, general plastic insulated cables, steel tape armored cables, steel wire armored cables, anti-corrosion cables, etc. can be selected;
According to the safety requirements, flame retardant cables, halogen-free flame retardant cables, fire-resistant cables, etc. can be selected.
Second, the selection of cable specifications.
1.When determining the usage specifications (conductor cross-section) of wires and cables, conditions such as heat generation, voltage loss, economic current density, and mechanical strength should be considered. According to experience, because of its large load current, the cross-section of the low-voltage power line is generally selected according to the heating condition, and then the voltage loss and mechanical strength are checked.
2.Due to its high requirements for voltage level, the cross-section of the low-voltage lighting line can be selected according to the allowable voltage loss condition, and then the heating condition and mechanical strength can be checked.
3.For high-voltage lines, the cross-section is selected according to the economic current density, and then the heating conditions and allowable voltage loss are checked.
4.The mechanical strength of high-voltage overhead lines should also be calculated. If the user has no experience, the relevant professional units or persons should be consulted.
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Anonymous users2024-02-14High voltage refers to the voltage above 35kv, only a single core, can not be made into three cores, it is not safe to use three cores, it is recommended not to use.
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Anonymous users2024-02-13Of course, the high-voltage line is generally a 3-core cable.
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Anonymous users2024-02-12Summary. Kiss can also refer to: but it is not recommended to coil together Three-phase cables are coiled together during use because the cables are too long, and self-inductive electromotive force is generated in the circuit, which hinders the change of current and forms an inductive reactance.
This can cause the cable to heat up or even damage the cable. Three wires piercing the same iron pipe will not produce eddy currents, but there will be circulation between three cables wearing the same iron pipe, which will cause the cable to heat up, thereby reducing the theoretical current carrying capacity of the cable and affecting the service life of the cable, so this method is not allowed. <>
Hello Hello Hello <>Hello Hello
The three cables of the high-voltage single core can be coiled together.
Kiss can also refer to: but it is not recommended to coil together Three-phase cables are coiled together during use because the cables are too long, and self-inductive electromotive force is generated in the circuit, which hinders the change of current and forms an inductive reactance. As a result, the cable will be heated and even damaged and the cable will be damaged.
Three wires worn in the same iron pipe will not produce eddy currents, but there will be a circulation between the three cables in the same iron pipe, which will cause the cable to heat up, thereby reducing the theoretical current carrying capacity of the cable and affecting the service life of the cable. <>
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Anonymous users2024-02-11Summary. Pro-<>
Hello <>
We'll be happy to answer for you. In general, the third core of the three-core cable is the grounding wire, and the first and second cores are load lines, which can be used to connect the power supply of electrical appliances.
Can the three-core cable be used for the local wire?
Hello <> dear <>
We'll be happy to answer for you. The three-core cable can be used on the ground but should be installed according to the actual situation, in general, the three-core cable in the first Qing family is the grounding wire, the first core and the second core are the load line, which can be used to connect the power supply of the electrical appliances. Envy scum.
Hello Kiss Expand information: Three-core cable advantages: 1
High stability: The three wires of Sanchang Paidan core cable are wrapped independently, which makes the cable more stable than the double-core cable, reduces line interference and electromagnetic wave interference, and can provide higher quality signal transmission. 2.
Strong versatility: Three-core cables are widely used in power, communications, transportation, control and other fields, and can be used to transmit high, low voltage, high and low frequency signals and He Tsai data. 3.
High safety: The three-core cable wraps a protective layer on the outer layer of the wire, which can prevent leakage or short circuit, and effectively improve the safety of the wire. 4.
Wide range of application: three-core cable, also known as three-core power cord, can be used in most low-voltage electrical appliances such as ordinary household disturbance resistant appliances, audio equipment, televisions, etc., with a wide range of applications and easy to use. 5.
Strong anti-interference: the three wires of the three-core cable are wrapped separately, which can effectively prevent the wire from receiving external interference and causing noise, and improve the transmission quality of the wire.
I screwed the three wires together, and then connected one end to the angle iron and the other end to the electrical box.
Kiss so that you can connect the electrical box to the angle iron.
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Anonymous users2024-02-10This is because the high-voltage uses three symmetrical power supply.
High-voltage transmission is generally transmitted underground by insulated cables in cities, and overhead lines carried by iron towers are often used in the field.
High-voltage lines usually refer to transmission lines that carry voltages above 10kV. Depending on the GB, the high voltage usually does not contain 1000V.
The purpose of high-voltage transmission itself is to reduce the loss of electric energy, and the loss of electric energy can be reduced by changing the cross-sectional area when the length of the conductor cannot be changed.
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Anonymous users2024-02-09It is because the high voltage uses a symmetrical power supply of three reeds.
1. Three-symmetrical power supply, no need for zero line.
2. According to the provisions of GBT20050-2008, the high-voltage line usually does not meet the 100 high-voltage line, which usually refers to the transmission line that sends 10kV (will 10kV) to voltage.
3. The three-level standard power supply has the advantages of high power, high efficiency, low cost and low loss in power generation and production cost.
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Anonymous users2024-02-08Gaosen pressure adopts a three-phase four-wire system, because the 10kv, 6kv and above lines are mainly used to transmit electric energy, and the electricity emitted by the engine is a, b, c three-phase electricity, and the lines drawn from the engine are three, so the high-voltage lines are three.
The minimum distance between the line and the ground, in the case of the maximum calculated sag, should not be less than the following values:
The low-voltage line (380V) shall not be less than 6 meters through residential areas, and the low-voltage line (380V) shall not be less than 5 meters through non-residential areas;
Medium-voltage lines (6-10kv) through residential areas are not less than meters, and medium-voltage lines (6-10kv) through non-residential areas are not less than meters;
The 35 110kV line shall not be less than 7 meters through residential areas, the 35 110kV line shall not be less than 6 meters through non-residential areas, and the 35 110kV line shall not be less than 5 meters through areas with difficult traffic;
The 154 220kV line passes through residential areas not less than meters, the 35 110kV line passes through non-residential areas not less than meters, and the 35 110kV line passes through areas with difficult traffic not less than meters;
The 330kV line passes through residential areas not less than meters, the 35 110kV line passes through non-residential areas not less than meters, and the 35 110kV line passes through difficult traffic areas not less than meters.
There is no clear distance regulation in China regarding the safe distance between the high-voltage line and the residential building, but there is a relevant standard that can be converted into a local leak: the magnetic induction intensity of the location of the residential building < 100 microtesla, which meets the construction standard. Measured:
The safety distance of the high-voltage line below 1kV is 4 meters;
The safety distance of 1-10kv high-voltage line is 6 meters;
The safety distance of 35-110kv high-voltage line is 8 meters;
The safety distance of 154-220kV high-voltage line is 10 meters;
The safety distance along the 350-500kv high line is 15 meters.
The recommendation for automotive high-voltage wires is to replace them once every 4-50,000 kilometers. Once the high-voltage line is damaged or aged and not replaced in time, the energy value of the ignition will be greatly reduced, the fuel consumption will rise, the power will decrease or even the fire will be cut off.
The high-speed rail will not have to be built not far from the high-voltage line, and the high-speed rail will be repaired according to his route and needs, and it has nothing to do with the distance of the high-voltage line.
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