According to instrument shell protection performance.docVIP

According to instrument shell protection performance, can be divided into common type, dust-proof, airtight, splash proof, waterproof, watertight and flame-proof type, etc. (6) according to the classification, the performance of instrument defense outside magnetic field or electric field can be divided into 1, 2, 3, 4 four grades. Instrument at all levels under the influence of outer magnetic field of an electric field or allow it to change quantity should comply with the provisions of the indicated value. (7) according to the accurate classification, can be divided into seven. Instrument accuracy level: 0.1, 0.2, 0.5, and 1.0, 1.5, 2.5, 5.0. 2. The performance of electrical measuring instruments Electrical measuring instrument is determined by the measured object, the performance of the measured object is different, different performance. Measuring objects include current, voltage, power, frequency, phase, power, resistance, capacitance and inductance parameters, as well as the magnetic field intensity, magnetic flux, magnetic induction intensity, magnetic hysteresis, eddy current loss and permeability parameters. With the progress of technology, integrated circuit as the core of digital instrumentation, microprocessor as the core of intelligent measuring instrument has obtained the development and application of high speed. The instrument not only has the function of the conventional measurement and display, and usually with parameter Settings, switch interface, data communication, etc. [note: inductor is the ability to store electrical energy into magnetic energy and up components. The structure of the inductor is similar to the transformer, but only one winding. Inductance equipment has certain inductance, it only hinder the change of the current. If there is no current through the inductor in the state, the circuit switched on when it will attempt to hinder the current flows through it; if you have any current through inductor in the state, the circuit