How many volts is the voltage in the signal cable

Buy wire and cable to see the quality, to have national standard certification and other qualification certificates, the current market is better is the sail cable, the quality is excellent, and more affordable than peers, after all, it is an old brand, recommended sail cable, I hope mine is helpful to you. At present, Qifan specializes in the manufacture of 220kV and below high and low voltage power cables, wires and cables for electrical equipment, civil cloth wires, overhead insulated cables, computer cables, control cables, rubber cables, aluminum alloy cables, low-smoke halogen-free cables, flame-retardant and fire-resistant cables, mineral insulated cables, irradiation cross-linked cables, prefabricated branch cables, and polar cold-resistant cables, robot cables, ship cables, automobile cluster wires, aerospace cables, nuclear power plant cables, high-voltage and ultra-high-voltage cables, etc. Tens of thousands of specifications, products are widely used in municipal, water...

Each cable has a label, such as a weak wire voltage 450v 750v, there will be such words.

Wire and cable: Wire and cable are wire products that transmit electrical energy, electrical signals and realize electromagnetic energy conversion. Cables usually consist of a core that transmits electricity or signals and a sheath that protects and insulates them.

Cables that contain only one core and are thinner in diameter are often referred to as wires. There are also wires that are not insulated and are called bare wires. The core in the cable is made of a metal material that conducts electricity well, usually using copper (which conducts well) or aluminum (which is less expensive).

The so-called line voltage refers to the voltage between lines 380V, and the phase voltage is 220V between lines and zero.

Phase voltage: The voltage between the live wire and the neutral wire. The phase voltage in our country is 220 volts, 50 Hz.

Line voltage: The voltage between the live wires and the live wires. The line voltage in China is 380 volts, 50 Hz.

Phase voltage, the voltage between the three-phase transmission line (live wire) and the neutral wire is called phase voltage. For example, the voltage in the three-phase four-wire system in the daily electricity system is 380 220V, that is, the line voltage is 380V, and the phase voltage is 220V.

Line voltage, the voltage between each line (live wire) of the three-phase transmission line is called the line voltage, and the size of the line voltage is a multiple of the phase voltage.

Difference Between Line Voltage and Phase Voltage:

For phase voltage, it is generally understood as the voltage between phases, that is, 380V, and the line voltage is understood as 220V.

The phase voltage refers to the voltage between the phase wire, that is, the live wire and the neutral line, and the line voltage is the voltage of any two live wires on the line, that is to say, the phase voltage should be 220V, and the line voltage is 380V.

What comes out of the power plant are three live wires (line voltage). In the use of a transformer to boost the voltage to transport out, the point used is to use a step-down transformer to step down to 400V (still the voltage of the three live wires).

The neutral wire is drawn from the contacts of the three sets of coils of the winding of the step-down transformer, and the transformer is star-shaped, and the four wires here are aligned.

In the receiver through the electric cabinet respectively received the user (load). The three live wires are generally named A, B, C, and the neutral line is n. With a line voltage of 380V, it is connected to A, B, and C. Families are using an, bn, cn. Both 220V phase voltage.

The voltage of the <> line is about 50 volts when the phone hangs up, about 10 volts when it goes off-hook, and its ringing voltage is about 80 volts when there is a ** call-in, and when the bell rings, the ringing voltage is 75 volts, and the frequency is 16 to 25 Hz AC voltage.

At present, the program-controlled switch used, the DC feed voltage is 48 volts, because the lead-acid battery is float charged, the actual voltage is about 50 volts DC when the machine hangs up, when the machine is off-hook, the DC circuit of the phone is turned on, and there is a current in the phone, at this time the voltage drops to 7 to 10 volts, depending on the length of the line, the phone is different.

**The current of the line is very small, and the current in the off-hook state is about 20 to 30 milliamperes, which will not directly cause harm to the human body.

1. How many volts there are in the high-voltage wire, it depends on the place. The average city should be one or two hundred thousand volts. Within the city it may be tens of thousands to thousands of volts.

There may be hundreds of thousands of volts between provinces, and the highest is about one million volts. 2. According to the voltage safety level, it can be divided into: safety voltage

Usually below 36V, the national regulations below 42V; According to the national standard "GB3805-83" safety voltage, the voltage series used to prevent electric shock accidents and supplied by a specific power supply is specified. China stipulates the following five levels for power frequency safety voltage, namely 42V, 36V, 24V, 12V and 6V). Low pressure:

1000V or less, 220V and 380V are more typical; High voltage: AC 1000V and above voltage is collectively referred to, DC 800KV and below is called high voltage. The more typical ones are 10kv-220k; Ultra-high pressure:

330kv-750kv；5: UHV: 1000kV AC, 800kV DC or above; ）。

3. According to the difference between high and low voltage, it is based on the voltage value of electrical equipment to the ground. The voltage to the ground is higher than or equal to 1000V. The voltage to the ground is less than 1000V, which is low voltage.

That is, AC 1000V and above voltage is high-voltage voltage.

The standard line voltage is 380V, and 400V is not normal according to the pass rate of +7% and -10% respectively for the allowable deviation of 220V single-phase power supply voltage.

The reason for the voltage drop of the cable In English, "voltagedrop" is the voltage drop, and "drop" means "to pull down". The voltage drop in a power line is due to the presence of resistance in the conductor. Because of this, no matter what kind of material (copper and aluminum) is used in the conductor draft, it will cause a certain voltage loss of the line, and this loss (voltage drop) is not greater than 5% of its own voltage, and it will not have consequences for the electric drive of the line.

For example, if the voltage drop of a 380V line is 19V, that is, the circuit voltage is not lower than 361V, there will be no big problem. Of course, we want this pressure drop to be as small as possible. Because the pressure room itself is a kind of power loss, although it is inevitable, we always hope that the pressure drop is within an acceptable range.

Calculation formula of line voltage dropIn general, calculating the voltage drop of the line is not complicated, and the following steps can be used. Calculate line current ii=p Where: p - power (kW); u-Voltage(kv); cos - power factor (.

The XXKV voltage system in China refers to the line voltage of the power supply system, so in the 0kV system, the power line voltage is 10kV. Considering the problem of the voltage drop of the power supply side and the load side, the general power supply side is 10kV on the load side, and the power supply side is 5% higher than the load side to make up for the voltage drop of the line.

Although the 10kV system is a low-current grounding system and generally does not have a neutral lead-out, there is generally no phase voltage for the load. However, when measuring the power supply, there is still the voltage of the power supply side to the neutral point, including the phase voltage sail key through the electric bench during the protection, and the phase voltage is: 10 3=.

6 The 10kV system generally adopts the operation mode of neutral point suspension, or grounding through the arc suppression coil, and the voltage of the single opposite ground is also called the phase voltage.

Generally, high-voltage lines are usually transmission lines that transmit voltages of more than 10kV (including 10kV). According to China's high-voltage policy, high-voltage usually does not contain 1000V. The voltage levels of China's domestic high-voltage transmission lines are generally divided into:

35kv, 110kv, 220kv, 330kv, 500kv, 750kv, etc. Among them, 110kV and 330kV are mostly used in the northern region. Generally, the transmission voltage below 220 kV is called high-voltage transmission, the transmission voltage between 330 and 750 kV is called ultra-high voltage transmission, and the transmission voltage above 1000 kV is called UHV transmission.

The safety distance between the high-voltage line and the residents: 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 distance between the high-voltage line and the ground: 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) through the residential area is not less than 6 meters, and the low-voltage line (380V) through the non-residential area is not less than 5 meters; 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; 154 220kV line through residential areas not less than meters, 154-220kV line through non-residential areas not less than meters, 154-2200kV line through traffic difficult areas not less than meters; The 330kV line is not less than a meter through residential areas, the 330kV line is not less than a meter through non-residential areas, and the 330kV line is not less than a meter through the royal chain traffic difficult areas.

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.