The power sensor is a detecting device that can sense the information of the measured power and can transform the detected information into an electrical signal or other required form of information to meet the information transmission and processing. Requirements for storage, display, recording, and control. It is the first step in achieving automatic detection and automatic control. It is also a device that converts measured power parameters (such as current, voltage, power, frequency, power factor, etc.) into DC current, DC voltage and isolates the output analog signal or digital signal. The product conforms to the national standard GB/T13850-1998. Note: True RMS voltage and current transmitters are used to measure voltage or current signals with severe waveform distortion in the power grid. They can also measure non-sinusoidal waveforms such as square waves and triangular waves.
principle
When the power sensor output information meets certain standard requirements, it is also called the power transmitter.
With the continuous development of science and technology, industrial control or detection (monitoring) systems are increasingly demanding electrical isolation sensors, especially in terms of product stability, detection accuracy and functionality. Analog products are incomparable due to their performance and functionality, such as nonlinear correction and small signal processing. Therefore, the digitization of the power sensor is an inevitable trend. Power technology with sensing detection, sensing sampling, and sensing protection is becoming a trend, and sensors for detecting current or voltage have emerged as the times require and are favored by power supply designers in China.
Characteristic parameter
Rated output: 0 ~ 5Vdc; 0 ~ 20mA; 4 ~ 20mA;
Accuracy: 1.0;
Linear range: 0 to 120%;
Response time: ≤300mS;
Isolation withstand voltage: 2500V DC / 1 minute;
Working temperature: -20 ° C ~ +70 ° C;
General technical conditions
â— Reference standards and rules: GB/T13850-1998
◠Relative humidity: ≤93%
â— Accuracy level: 0.2, 0.5
◠Storage conditions: temperature -40~+70°C, relative humidity 20~90%, no condensation
◠Working temperature: -10~55°C
◠Mean time between failures: ≥30000h
Basic classification
According to the characteristics of the input signal, it can be divided into:
DC battery sensor
The most common are shunts, resistor dividers, etc.;
AC power sensor (usually suitable for power frequency sine wave measurement)
The most common are electromagnetic voltage transformers, capacitive voltage transformers, electromagnetic current transformers, etc.;
Inverter power sensor (for AC power measurement of various frequencies and waveforms)
Such as Hall voltage sensor, Hall current sensor, Rogowski coil and variable frequency power sensor. Power frequency is a special case of variable frequency power. Therefore, the variable frequency power sensor can usually be used as a power frequency AC power sensor. In addition, in addition to the Rogowski coil can not be used for DC measurement, several other sensors can also be used as DC power sensors. .
The power isolation sensor is divided into the following six categories according to the detection of the power signal and function.
current sensor
Voltage sensor
Frequency sensor
Power sensor
Temperature Sensor
Cross-line alarm sensor
According to the characteristics of the output signal, it can be divided into:
Analog output power sensor and digital output power sensor, variable frequency power sensor is a digital output power sensor.
Since the digital fuel cell can directly output digital quantities, the A/D acquisition module can be omitted for many applications, which can alleviate system design work. Moreover, compared with the analog quantity, the anti-interference ability of the digital signal is strong, especially the digital signal can be conveniently transmitted by optical fiber, which can completely avoid the loss and interference of the transmission link, and provides a scientific way for realizing high-precision measurement in a complex electromagnetic environment. Protection.
Due to the variety of power sensor products, this paper only introduces a digital signal technology for AC signal power sensors. There are many ways to realize the digitalization of the power sensor. At present, the most common one is the microprocessor technology such as single chip microcomputer, DSP, FPGA, etc., because its application is flexible and can realize various functions. With the continuous development of integrated circuits, many specialized chips have emerged, such as watt-hour meter products, and there are many special-purpose chips available, including digital interfaces and pulse outputs.
related information
Measuring instrument
1 Sensor ARCM-NTC sensor ARCM-NTC directly acts on the device that is measured and can be converted into the same or other kinds of magnitude output according to certain rules.
2 Transmitter P/Q combination transmitter BD-3P/Q/I output is a standard signal sensor.
3 A device or substance that is used to indicate the presence of a certain amount without having to provide a magnitude.
4 The power isolation sensor is a sensor that uses non-electrical media to isolate the measured power and output signals into a specified electrical signal between the measured power and the output signal.
Two measurements
1 The amount to be measured is measured.
2 The amount of influence is not the measured object but affects the measured value or the amount indicated by the measuring instrument. Such as: the frequency when measuring AC voltage.
Three measuring instrument characteristics
1 Accuracy metering device gives the ability to approximate the value of the measured true value.
2 The level or level of accuracy of the measuring instrument (which meets certain measurement requirements and keeps its error within the specified limits).
3 The modulus of the difference between the upper and lower limits of the range measurement range. |Upper limit value - Lower limit value |
4 Standard operating conditions (reference operating conditions) Conditions for the use of measuring instruments specified for performance testing or to ensure that the measurement results are effectively aligned with each other. Such as: reference temperature range 15 ° C ~ 35 ° C
5 Rated operating conditions The normal conditions of use specified for the specified metering characteristics of the measuring instrument to be within the given limits. Such as: rated temperature range 0 ° C ~ 50 ° C
6 Extreme operating conditions The extreme conditions specified in order to prevent damage to the measuring instrument or to permanently reduce the metering characteristics. Such as: the limit temperature range -10 ° C ~ +70 ° C
7 The nominal value is marked on the appliance to indicate its characteristics or to guide the use of the value. Such as: the resistance value marked on the resistance, the weight value, the output value on the sensor label.
8 The nominal input value is the input value or input range of the measuring instrument specified to keep the metering characteristics specified by the measuring instrument within a given limit.
Four measurement errors
1 The difference between the absolute error measurement result and the measured true value (expected value, ideal value).
2 The ratio of the absolute error of the relative error measurement to the true value being measured.
3 The absolute value of the error does not take into account the error value of the sign.
Five measuring instruments error
1 Basic error (inherent error) The error that the measuring instrument has under standard conditions. Such as: linearity error, ripple, response time, backlash error, etc.
2 Additional error (impact error) The error that the measuring instrument has under non-standard conditions. Such as: temperature influence, humidity influence, auxiliary power supply influence, influence of measured frequency, influence of measured voltage, influence of measured power factor, etc.
3 Reference the ratio of the absolute error of the error measuring instrument to its range.
4 Maximum deviation between the linear error standard curve and the specified straight line.
5 The return error is the same under the same conditions, the measured value is unchanged, and the stroke direction of the measuring instrument is different from the absolute value of the difference between the indicated values.
6 The deviation of the actual step characteristic and the ideal characteristic from which the quantization error is measured.
Six values
1 RMS: The square root of the mean of the instantaneous value over a period of one cycle. Or 曰 "root mean square value". Vrms = = Vp = 0.707 Vp 2 Average: The average of the instantaneous values ​​over a half cycle. Vavg = = Vp = 0.636 Vp
principle
When the power sensor output information meets certain standard requirements, it is also called the power transmitter.
With the continuous development of science and technology, industrial control or detection (monitoring) systems are increasingly demanding electrical isolation sensors, especially in terms of product stability, detection accuracy and functionality. Analog products are incomparable due to their performance and functionality, such as nonlinear correction and small signal processing. Therefore, the digitization of the power sensor is an inevitable trend. Power technology with sensing detection, sensing sampling, and sensing protection is becoming a trend, and sensors for detecting current or voltage have emerged as the times require and are favored by power supply designers in China.
Characteristic parameter
Rated output: 0 ~ 5Vdc; 0 ~ 20mA; 4 ~ 20mA;
Accuracy: 1.0;
Linear range: 0 to 120%;
Response time: ≤300mS;
Isolation withstand voltage: 2500V DC / 1 minute;
Working temperature: -20 ° C ~ +70 ° C;
General technical conditions
â— Reference standards and rules: GB/T13850-1998
◠Relative humidity: ≤93%
â— Accuracy level: 0.2, 0.5
◠Storage conditions: temperature -40~+70°C, relative humidity 20~90%, no condensation
◠Working temperature: -10~55°C
◠Mean time between failures: ≥30000h
Basic classification
According to the characteristics of the input signal, it can be divided into:
DC battery sensor
The most common are shunts, resistor dividers, etc.;
AC power sensor (usually suitable for power frequency sine wave measurement)
The most common are electromagnetic voltage transformers, capacitive voltage transformers, electromagnetic current transformers, etc.;
Inverter power sensor (for AC power measurement of various frequencies and waveforms)
Such as Hall voltage sensor, Hall current sensor, Rogowski coil and variable frequency power sensor. Power frequency is a special case of variable frequency power. Therefore, the variable frequency power sensor can usually be used as a power frequency AC power sensor. In addition, in addition to the Rogowski coil can not be used for DC measurement, several other sensors can also be used as DC power sensors. .
The power isolation sensor is divided into the following six categories according to the detection of the power signal and function.
current sensor
Voltage sensor
Frequency sensor
Power sensor
Temperature Sensor
Cross-line alarm sensor
According to the characteristics of the output signal, it can be divided into:
Analog output power sensor and digital output power sensor, variable frequency power sensor is a digital output power sensor.
Since the digital fuel cell can directly output digital quantities, the A/D acquisition module can be omitted for many applications, which can alleviate system design work. Moreover, compared with the analog quantity, the anti-interference ability of the digital signal is strong, especially the digital signal can be conveniently transmitted by optical fiber, which can completely avoid the loss and interference of the transmission link, and provides a scientific way for realizing high-precision measurement in a complex electromagnetic environment. Protection.
Due to the variety of power sensor products, this paper only introduces a digital signal technology for AC signal power sensors. There are many ways to realize the digitalization of the power sensor. At present, the most common one is the microprocessor technology such as single chip microcomputer, DSP, FPGA, etc., because its application is flexible and can realize various functions. With the continuous development of integrated circuits, many specialized chips have emerged, such as watt-hour meter products, and there are many special-purpose chips available, including digital interfaces and pulse outputs.
related information
Measuring instrument
1 Sensor ARCM-NTC sensor ARCM-NTC directly acts on the device that is measured and can be converted into the same or other kinds of magnitude output according to certain rules.
2 Transmitter P/Q combination transmitter BD-3P/Q/I output is a standard signal sensor.
3 A device or substance that is used to indicate the presence of a certain amount without having to provide a magnitude.
4 The power isolation sensor is a sensor that uses non-electrical media to isolate the measured power and output signals into a specified electrical signal between the measured power and the output signal.
Two measurements
1 The amount to be measured is measured.
2 The amount of influence is not the measured object but affects the measured value or the amount indicated by the measuring instrument. Such as: the frequency when measuring AC voltage.
Three measuring instrument characteristics
1 Accuracy metering device gives the ability to approximate the value of the measured true value.
2 The level or level of accuracy of the measuring instrument (which meets certain measurement requirements and keeps its error within the specified limits).
3 The modulus of the difference between the upper and lower limits of the range measurement range. |Upper limit value - Lower limit value |
4 Standard operating conditions (reference operating conditions) Conditions for the use of measuring instruments specified for performance testing or to ensure that the measurement results are effectively aligned with each other. Such as: reference temperature range 15 ° C ~ 35 ° C
5 Rated operating conditions The normal conditions of use specified for the specified metering characteristics of the measuring instrument to be within the given limits. Such as: rated temperature range 0 ° C ~ 50 ° C
6 Extreme operating conditions The extreme conditions specified in order to prevent damage to the measuring instrument or to permanently reduce the metering characteristics. Such as: the limit temperature range -10 ° C ~ +70 ° C
7 The nominal value is marked on the appliance to indicate its characteristics or to guide the use of the value. Such as: the resistance value marked on the resistance, the weight value, the output value on the sensor label.
8 The nominal input value is the input value or input range of the measuring instrument specified to keep the metering characteristics specified by the measuring instrument within a given limit.
Four measurement errors
1 The difference between the absolute error measurement result and the measured true value (expected value, ideal value).
2 The ratio of the absolute error of the relative error measurement to the true value being measured.
3 The absolute value of the error does not take into account the error value of the sign.
Five measuring instruments error
1 Basic error (inherent error) The error that the measuring instrument has under standard conditions. Such as: linearity error, ripple, response time, backlash error, etc.
2 Additional error (impact error) The error that the measuring instrument has under non-standard conditions. Such as: temperature influence, humidity influence, auxiliary power supply influence, influence of measured frequency, influence of measured voltage, influence of measured power factor, etc.
3 Reference the ratio of the absolute error of the error measuring instrument to its range.
4 Maximum deviation between the linear error standard curve and the specified straight line.
5 The return error is the same under the same conditions, the measured value is unchanged, and the stroke direction of the measuring instrument is different from the absolute value of the difference between the indicated values.
6 The deviation of the actual step characteristic and the ideal characteristic from which the quantization error is measured.
Six values
1 RMS: The square root of the mean of the instantaneous value over a period of one cycle. Or 曰 "root mean square value". Vrms = = Vp = 0.707 Vp 2 Average: The average of the instantaneous values ​​over a half cycle. Vavg = = Vp = 0.636 Vp
Capacitor For Electric Furnace
Capacitor for Electric Furnace, commonly referred to as capacitors, are capacitors, expressed in the letter C.Definition 1: a capacitor, as the name implies, is a "charging vessel", a device that holds charge.Capacitor.Capacitors are one of the most widely used electronic components in electronic equipment. They are widely used in the fields of interleaving, coupling, bypass, filtering, tuning circuit, energy conversion and control.Definition 2: a capacitor consisting of any two conductors (including wires) that are insulated from each other and are very close together.
Components Capacitors,High Voltage Capacitors,Low Frequency Capacitor,Water Pump Capacitor,Capacitor for Electric Furnace
YANGZHOU POSITIONING TECH CO., LTD. , https://www.cnfudatech.com