Usage:Magnetic Sensor
Type:Optical-Electronics Sensor
Theory:Hall Sensor
Output:Analog Sensor
Model Number:JLK-7DC300A
Material:Polymer
Output model class:Analog sensor
Working principle:Magnetic sensor
Sensor class:Energy consumption sensor
Texture of material:polymer
1 open loop current sensor principle: magnetic flux generated by the primary side current IP high quality core aggregation in the magnetic circuit, Holzer element is fixed in the air gap is small, the linear detection of magnetic flux, the output voltage Holzer Holzer devices through a special circuit processing, secondary output and primary side output voltage waveform consistent with this voltage, can accurately reflect the changes of the primary current. A current sensor can Holzer current measurement of various types, from DC to tens of kHz alternating current, the working principle of the basis of Holzer is the main effect of B when the primary guide line passes through the current sensor, the primary current IP will produce magnetic field lines, the original focus on the core around the edge, the built-in Holzer electrode in the core gap in the produce and the primary magnetic flux is proportional to the size of the voltage of only a few millivolts, the electronic circuit To change this tiny signal into the secondary side current is IS, and the following relation: C when the primary side current IP flows through a long wire, will produce a magnetic field around the wire, and the size of the current flows through a wire is directly proportional to the magnetic field, the magnetic field produced by Holzer gathered in the ring. The magnetic element in the air gap is measured and output, the output voltage of the VS accurately reflect the current of primary side IP. The nominal output rating is generally 4V.
Holzer sensor advantages
1., a wide range of measurement: it can measure any waveform of the current and voltage, such as DC, AC, pulse, triangle waveform, etc., and even the transient peak current and voltage signals can also be faithfully reflected;
2. fast response: fastest response time is only 1us.
3., the measurement accuracy is high: its measurement accuracy is better than 1%, the accuracy is suitable for any waveform measurement. The common transformer is an inductive component, which influences the waveform of the measured signal after its insertion. Its general accuracy is 3%~5%, and it is only suitable for the 50Hz sinusoidal waveform.
4. linearity: better than 0.2%
5., dynamic performance is good: response time fast, can be less than 1US; common transformer response time is 10~20ms.
6. bandwidth: signals within the 0~100KHz frequency range can be measured.
7., high reliability, average trouble free working time is long: the average trouble free time is >5 10 hours
8., overload ability, measuring range: 0--- dozens of AMPS ~ tens of thousands of amperes
9. small in size and light in weight
When using the B Holzer current sensor, the following precautions should be followed:
1, in order to obtain better dynamic characteristics and sensitivity, it is necessary to pay attention to the coupling of the primary coil and the auxiliary coil. It is necessary to have a good coupling. It is better to use a single wire and the wire is fully filled with the aperture of the Holzer sensor module.
2, when the DC current flowing through the primary coil of the sensor, and the secondary circuit is not connected to the power regulator or | side open circuit, the magnetic circuit is magnetized, and remanence affects the measurement accuracy (when used to first turn on the power and the measuring end M), when this happens to demagnetization processing. The method is that the secondary circuit does not supply power, and in the primary coil, an alternating current of the same magnitude is added and the value is gradually reduced.
3, Holzer sensors have a strong ability to resist external magnetic interference, but in order to obtain higher measurement accuracy, when there is a strong magnetic field interference, we should take appropriate measures to solve. There are usually ways:
The direction of the module is adjusted so that the influence of the external magnetic field on the module is minimal;
Cover the module with a metal shield against the magnetic field.
4. The best accuracy of measurement is obtained under the rated value. When the current being measured is much lower than the rated value, the best accuracy can be obtained. The original side can use multi turns, but the space position of the conductor should be noted.
5 current sensors must be based on the rated current effective value, appropriate selection of different specifications of the product. If the current is measured for a long time, it will damage the terminal amplifier tube (magnetic compensation type), and in general, the overload time of 2 times shall not exceed 1 minutes.
6 voltage sensor must according to product specification in the original side into a current limiting resistor R1, so that the original side to obtain rated current, in general circumstances, 2 times the duration of overvoltage shall not exceed 1 minutes.
The best accuracy of 7 current voltage sensor is in the primary side of the rated value under the conditions, so when the measured current is higher than the rated current sensor, sensor should be chosen correspondingly large; when the measured voltage is higher than the rated value of the voltage sensor, should adjust the current limiting resistor. When the measured current is lower than the rated value is below 1/2, in order to get the best accuracy, can use multiple cycles of way.
8) insulation withstand voltage 3KV sensor can work normally for 1KV and below, AC system and 1.5KV and below DC system
The use of unit 9 at the request of good dynamic characteristics when using a single copper busbar and the best aperture with big generation small or more cycles, will affect the dynamic characteristics.
10 in the Holzer sensor high current direct current system, for some reason, the work power supply open circuit or malfunction, then the core produce bigger remanence, is worth noting. Remanence precision. The demagnetization method is without working power supply, communicating at the original edge and gradually decreasing its value.
11 sensor external magnetic field ability is: distance sensor 5 ~ 10cm, a more than the sensor original side current value 2 times the current, the resulting magnetic field interference can resist. For three-phase high current wiring, the phase distance should be greater than 5 to 10cm.
12, in order to make the sensor work in the best measurement state, it is better to use a regulated power supply.
13 magnetic saturation point and circuit saturation point of the sensor, so that it has a strong overload capacity, but the overload capacity is time limited. When the test overload capacity, more than 2 times the overload current shall not exceed 1 minutes.
14, the original side current, bus temperature shall not exceed 85 degrees, which is decided by the characteristics of ABS engineering plastics, users have special requirements, optional high temperature plastic shell. A in addition to the installation wiring, real-time calibration, calibration, pay attention to the work environment of sensors, through the following methods can also improve the measurement accuracy:
Application of Holzer current sensor [/b]
In recent years, high power transistor, thyristor rectifier and the use of a large number of automation system, AC frequency converter and PWM circuit is widely used, making the circuit not only the traditional 50 weeks of sine wave, different waveform appears. For this kind of circuit, the traditional measurement method can not reflect the real waveform, and the current and voltage detection components are not suitable for the sensing and detection of medium, high frequency and high di/dt current waveform.
A Holzer effect sensor that measures the current and voltage of an arbitrary waveform. The output can truly reflect the waveform parameters of the input current or voltage. Aiming at the shortcomings of the Holzer sensor temperature drift, is controlled by the compensation circuit can effectively reduce the temperature influence on the measurement accuracy, to ensure the accuracy of the measurement; has the characteristics of high precision, convenient installation, low price.
The Holzer sensor is widely used in inverter, inverter, UPS power supply, communication power supply, electric welding machine, electric locomotive, transformer substation, CNC machine, electrolytic plating, microcomputer monitoring, power monitoring and detection of current and voltage isolation facilities.
| | JLK-7DC300A/DC4-20ma | | Holzer current transducer |
| Working environment | ambient temperature | -25+80 | Storage temperature | -40+115 |
| relative humidity | ≤90% | Barometric condition | Normal atmospheric pressure |
| Electrical parameter | Rated current range | DC300A | Nonlinear error | 0.1% |
| output voltage | Ip=±Ipn DC5±1%V | Measuring current range | DC600A |
| Overload factor | Infinite | working frequency | 40-20khz |
| Work power | ±15V±5%V | Power waste | +35 -20ma |
| Insulation impedance | | Dielectric Strength | 2.5kV50hz1Min) |
| Offset voltage drift | -40-85±1MV/ | Output voltage drift | -40-85±1MV/ |
| Zero voltage | 25mv | Linearity | Ipo=0±Ipn1%FS |
| response time | 50A/us 10-90% 5us | bandwidth | 0-3Db 40-20khz |
| Mechanical parameter | Once through core | 25mm | Outline size | 75*74*22mm |
| Two terminal | 508 terminal connection | | |
| Shell | PBT flame retardant material | Potting | Epoxy resin adhesive |
| weight | 220g | tolerance | ±0.3mm |
| Offset voltage | Ipo ±30mv | Magnetic offset voltage | Ipo=±Ipn-0 ±30mv |
