Apply 50HZ power frequency voltage to the insulation gap or insulation medium until the gap or insulation medium discharges and breaks down. At this point, the voltage is the power frequency discharge voltage.
Power frequency voltage
Power frequency, 50Hz in China,
Power frequency voltage: line voltage
380v, 6kV,10kV, 35kV,10kV, 220kV, 500kV, 800kV.
What is the power frequency voltage? What is impulse voltage?
A: Sinusoidal AC voltage with frequency equal to 50Hz is called power frequency voltage. Surge voltage refers to the voltage with extremely short action time, such as lightning surge voltage or operating surge voltage.
What is power frequency electricity?
BS300 1 Power Frequency Electrical Parameter Tester (0.05 class) is a series of advanced equipment designed by General Instrument Company, combined with new computer software technology. The functional indexes of the whole machine meet the requirements of the verification method of electric energy metering and verification device and the relevant electric energy metering and verification regulations of the Ministry of Energy. The whole machine has advanced technology, complete functions, compact structure and reliable performance. It can be used as a measuring standard instrument in laboratories and standard rooms.
Main features:
Based on high-speed and high-precision A/D converter, three-phase AC voltage, current, phase and frequency are sampled at the same time, and the true effective values of each phase voltage and current are calculated by mathematical method.
Using mathematical phase-shifting method, the values of active power and reactive power of each phase are accurately calculated.
Using high stability voltage reference as reference, zero and full scale can be self-calibrated periodically.
The long-term stability and high-precision measurement of each range are realized by external calibration without opening the cover.
It can be widely used in laboratories, metrology institutes, power systems and other departments.
Adopt true color TFT display and Chinese menu operation mode.
It can be used as 0. 1 AC voltage, current and power, 0. 1 power frequency phase standard and 0.0 1 power frequency standard or on-site detection.
Voltage, current and power display modes (direct reading, 75 grid, 100 grid, 150 grid), with adjustment precision of 0.0 1%.
Low power consumption, about 15W.
Provide RS232 interface, which can be connected to PC or notebook computer for semi-automatic indicator detection, and can automatically print the test report.
Adopt light aluminum chassis, beautiful. Light weight, less than 9 kg.
Wide working power supply range (220v 5%)
All the key components are imported from foreign famous brand manufacturers, and the production process requirements are extremely strict, which ensures the reliability of the products.
Main technical indicators:
project
technical parameter
Body indicator
measure
quantity
transmit
flow
electric current
press
(three-phase)
The voltage range is 30 v, 60 v10 v150 v, 250 v, 300 v, 450 v, 60 v (extensible).
The measuring range is 0v ~ 800v.
The resolution is 0.00 1%
The voltage measurement accuracy is 0.65438 0%, 0.05% and 0.02% (optional).
The stability is 0.005%/ min.
measure
quantity
transmit
flow
electric current
flow
(three-phase)
The current range is 0. 1A, 0.25A, 0.5A, 1A, 2.5A, 5A, 10A, 25A, 50A, 100A (extensible).
The measuring range is 0a ~ 120a.
The resolution is 0.00 1%
The accuracy of measuring current is 0. 1%, 0.05%, 0.02% (optional) 50A, 100A 0.05%.
The stability is 0.005%/ min.
frequency measurement
The frequency range is 30.000- 1000 Hz.
The resolution is 0.00 1Hz
Accuracy 0.005 Hz
Phase difference measurement
The phase shift range is 0.00-360.00.
The resolution is 0.0 1
Accuracy 0.05 (current input ≥ 50% when voltage input ≥ 57V) 0.1(current input ≥ 10% when voltage input ≥20V)
(Yes) Reactive Power Measurement
Power range 0 ~ 60000 w
Accuracy 0.05% rg (cos φ/sin φ = 1, 0.5l, 0.5c) reactive power 0. 1%RG.
The stability is 0.005%/ min (cos φ = 1).
Power factor measurement
Power factor range-1.000 ~+ 1.000.
Accuracy 0.005
The resolution is 0.00 1
(Yes) Reactive Power Measurement
Accuracy 0.05% rg (cos φ/sin φ = 1, 0.5l, 0.5c) reactive power 0. 1%RG.
that
it
join
count
Measuring voltage input impedance R ≥ 2M.
The measured current input impedance is 0.1va.
Effective value of frequency measurement input voltage ≥ 10V.
The input voltage and current for phase measurement are 50V~400V, 5a ~ 10a (effective value).
The volume is 285 mm× 250 mm×110 mm (length× width× height).
Weighing 9 kg
The working power supply voltage range is 220VAC 5%, 50hz.
Working temperature is 5 ~ 45℃.
Working humidity
What is the power frequency voltage and voltage situation in the world?
Power frequency voltage refers to the unified standard voltage of power industry and electrical equipment stipulated by the state. Power frequency: refers to the frequency of industrial AC power supply, in hertz (HZ). The power frequency voltage of single-phase power supply in China is 50 Hz, 220V V. The power frequency voltage of three-phase power supply is 50 Hz and 380V V. Due to the imbalance of industrial development around the world and the colonial control during World War II, there is no unified international standard for power frequency voltage, and there are great differences in different countries and regions. The following are the power frequency voltages around the world.
Asia
Name of region or country: Power frequency voltage: Taiwan Province, Taiwan Province, China 1 10V/220V, 60Hz, Chinese mainland, China, 220V, 50Hz, 50Hz, Hong Kong 220v, Japan1/0v, Kanto 50Hz, Kansai 60hz, Korea100.
Europe
Name of region or country AC voltage Russia 220V, 50Hz UK 240V, 50Hz France 127V/220V, 50Hz Germany 220V, 50Hz Ireland 220V, 50Hz Italy 127V/220V, 50Hz Switzerland 220V, 50Hz Netherlands 220V, 50Hz Denmark 220V, 50Hz Poland 220.
Meizhou
Region or country name AC voltage US 1 10V or 220V, 60Hz, 460V, 60Hz, 3Ph Canada 120V or 240V, 60Hz Brazil 127V or 220V, 60Hz.
What is the power frequency voltage? What is impulse voltage?
A: Sinusoidal AC voltage with frequency equal to 50Hz is called power frequency voltage. Surge voltage refers to the voltage with extremely short action time, such as lightning surge voltage or operating surge voltage.
What are power frequency and frequency conversion?
When the frequency conversion-power frequency switching occurs, the frequency conversion bomber appears, which leads to various explanations, making the frequency conversion-power frequency switching an insurmountable threshold.
For example, some people say that "the phase sequence of inverter output must be consistent with the power frequency phase sequence before it can be cut in" and so on. If the phase sequence of the inverter output is really consistent with the power frequency, then when switching from frequency conversion to power frequency, the inverter will still explode and the air compressor will still trip. Obviously, the reason is definitely not because of any phase sequence, phase, etc.
I'll tell you a simple method. Use voltmeter to measure the voltage between inverter output and power frequency phase line. No matter how you adjust the phase sequence, phase or other output of the frequency converter, the measurement result is the power frequency 380V line voltage.
The voltage between the output end of the frequency converter and the power frequency phase line is the power frequency 380V line voltage. Can I switch between frequency conversion and power frequency directly? Can direct switching not explode or trip?
Therefore, the technical secret of frequency conversion-power frequency switching is that the output end of the frequency converter cannot be shorted to the power frequency. As long as the output end of the inverter can't be shorted to the power frequency, your method will certainly ensure the success of switching.
How to ensure that the output of inverter is not short-circuited to power frequency? The method is simple. You use a contactor 1 to disconnect the inverter output from the motor, then use a contactor 2 to connect the power frequency with the motor, and use the normally closed contact of contactor 1 to connect the electromagnetic coil of contactor 2, that is, contactor 1 and contactor 2 must be interlocked. This ensures that the output of the inverter will not be short-circuited with the power frequency, and your switch will never explode or trip again.
Precautions for operation:
1, to switch the power frequency motor, the parking mode is set to free parking, and soft parking is prohibited;
2. Cut off the contactor of the motor from the output end of the frequency converter, and the control stop button is the same as that of the frequency converter, that is, when the frequency converter stops, the contactor coil will be powered off, thus cutting off the connection between the motor and the frequency converter;
3. Cut off the contactor of the motor from the output end of the inverter, and its control start button is interlocked with the inverter start button, that is, the inverter can be started only after the contactor is connected to the motor;
4. The motor is connected to the power frequency contactor, and its coil control loop is controlled by the normally closed contact of the contactor at the inverter output cut-off motor to ensure that the inverter output cuts off the motor and is connected to the power frequency;
5. If the switching process is fast and accurate, that is, the shorter the time the motor runs out of power inertia, the smaller the speed drop, and the less "impact", that is, the motor switches at rated current;
6. Here, pay attention to the phase sequence when the motor is connected to the power frequency to ensure that the motor rotates uniformly after switching!
7, power frequency to the motor should be set up isolation circuit breaker;
"Switch the 400 kW motor and the high voltage side trips."
1, it seems that everyone has doubts about the switching power frequency of high-power motors;
2. Don't worry about the power generation problem when the motor moves inertia, but what causes the trip?
3. There are two issues worth considering. One is that after the large motor leaves the power supply, the winding still has electrostatic voltage due to the distributed capacitor, and there is operating overvoltage when switching;
4. The other is that the motor has not been completely separated from the frequency converter (for example, the arc has not been extinguished), and the power frequency is switched prematurely, forming a power frequency short circuit;
5. The solution is: first stop the inverter freely, then separate the motor from the inverter, and then switch to the power frequency, so that the switching trip caused by the above reasons can be discharged;
6. Be sure to control the time difference! ! !
The switching between frequency conversion and power frequency is controlled by PLC. The secret of the switch is that there should be a delay of 0. 1 second from frequency conversion free parking to motor removal, and a delay of 0.2-0.4 seconds from motor frequency conversion removal to power frequency connection, and the whole process should be completed within 0.5 seconds at most.
Power frequency voltage15min
Household power frequency voltage refers to AC 50HZ power supply voltage, which has nothing to do with voltage level, but only with voltage frequency.
What is the power frequency reference voltage?
The frequency of 50Hz AC is referred to as power frequency power supply for short, that is, the voltage is obtained from 50Hz AC power supply as a reference value or signal.
What is the undervoltage when the power frequency power drops?
The rated voltage of 220V is actually lower than198v; ; The rated voltage of 380V is actually lower than 342V, which is theoretically undervoltage. The allowable voltage fluctuation of general electrical appliances is 65438 00%. Before the transformation of rural power grid, the rural power consumption conditions were very poor. In order to adapt to the power supply situation of rural power grid, the voltage of equipment used by some electrical appliance manufacturers is more than 20% lower than the rated voltage.