Voltaic sensor and transformer how type selecting?

The voltaic clamp of 1% precision, but very regretful and current not so the voltaic clamp of high accuracy. We understand voltaic sensor below / the knowledge of transformer, facilitating everybody type selecting. Normally voltaic sensor / transformer is a changeover of big electric current be measured in order to facilitate to be the same as the small electric current with inphase frequency or realize segregation. According to different commutation principle, have commonly be based on door of effect of electromagnetism induction principle, suddenly Er, magnetic flux the voltaic sensor of these a few kinds of technologies / transformer. One, transformer of voltaic transformer electric current is similar to primary v/LIT all over the ground number is very few, sub the transformer with v/LIT all over the ground more number. Below good case the first time of class electric current become inverse ratio than be being compared with v/LIT all over the ground number, voltaic commutation scale with sub and rated electric current is tagged first, for example " 300A/5A " , state the electric current that be measured is 5A to electricity is exported when rating 300A. Because secondary coil all is put in leakage feeling and resistor first, and curve of magnetization of excitation electric current, core is nonlinear, can bring about transformer to produce ratio sum of errors phasic error. Use at metric the transformer accuracy of plan cost is commonly 0.

1~1 class. By transformer principle knowable, it cannot measure dc electric current, normally the design is labour frequency to measure, accuracy is the parameter below labour frequency, bandwidth is narrower, do not suit to be used at harmonic is analysed and be not sine to measure. Transformer of use electric current notices certainly cannot will sub open a way, will produce high pressure to endanger person and equipment security otherwise. 2, the core inside clamp of voltaic clamp electric current is divided into two parts, avoid to disconnect to be measured loop, special facilitate measure and use very extensive. Have be based on electromagnetism induction principle and suddenly Er effect two sort. The voltaic clamp that is based on electromagnetism induction principle and transformer are same, core is divided into two parts, core of the two parts when closing needs close together couple, clamp of some electric current is sub joined resistor output is voltage signal, the output that does not have internal resistance is voltaic signal. Be closed by two parts core the influence of degree, voltaic clamp precision compares transformer difference normally. The voltaic clamp that is based on electromagnetism induction no less also can measure communication only. The voltaic clamp that is based on suddenly Er effect machines an air gap to place Huoer component in core. Use suddenly Er component to measure the magnetic induction intensity in air gap, differ according to controlling fashion, have open loop and closed circuit two sort. The suddenly Er element with open loop suddenly Er use nicer degree of linearity, suddenly Er component outputs voltage direct ratio at be being measured electric current. Closed circuit suddenly Er use technology of 0 magnetic flux, there is compensation coil on core. When class has the electric current that be measured to produce magnetic flux in core first, suddenly Er component detects the magnetic induction intensity in core, it is voltaic drive to compensate coil through losing feedback to change this error voltage, the magnetic flux in quits core, be measured finally electric current and the flux size that compensate coil generation are consistent way is opposite, be measured through measuring the electric current that compensates coil to be able to compare conversion to go out according to v/LIT all over the ground number electric current. Clamp of open loop and closed circuit suddenly Er electric current can measure dc and communication. Open loop suddenly Er suffers core nonlinear with Huoer the influence such as component temperature character, precision and degree of linearity are poorer, but cost is low. The degree of linearity to suddenly Er component depends on closed circuit suddenly Er lesser, core job falls in 0 magnetic flux, what compare open loop because of this precision is tall. But core of activity of voltaic clamp existence closes degree is paid no attention to consider an issue, not was equal to excel almost 0.

Of 1% , can accomplish 1% had been very high index. Suddenly Er component needs to offer working voltage, because clamp of these two kinds of electric current wants power supply, report of bad news of coil of compensation of drive of need of closed circuit suddenly Er is bigger. 3, sensor of electric current of the type that close a mouth normally like clamp of Huo Er electric current, also have open loop and closed circuit suddenly Er two sort, output is electric current or voltage signal. Because shut buccal form, the voltaic clamp precision that compares same kind is tall. Have the voltaic sensor that uses technology of magnetic flux door additionally, precision excel 0.

05% , achieve 12ppm even, but this sort sensor is very costly and very flimsy. Once in use did not fall to circumstance of sensor power supply, have the electricity that be measured, can cause sensor damage. 4, voltaic sensor / transformer and electric current of analyzer of power of PA5000 of power analyzer join are measured direct input and sensor input two groups of port, the sensor that should use / when transformer output is voltaic signal, the electricity that receives PA5000 inputs port directly, use sensor according to place / transformer installs PA correctly " CT " coefficient of proportionality, be like 300A/5A, criterion CT=300A/5A=60. The voltaic sensor that should use / when voltaic transformer output is voltage signal, the exterior sensor port that receives PA5000 (BNC interface) , use sensor according to place / transformer installs PA correctly " sensor rate " , the unit is MV/A, if voltaic clamp parameter is 1000A changeover to be 1V, criterion sensor rate is set for 1mV/A. CNC Milling CNC Machining