Electrical instruments are collectively required to achieve electromagnetic measurement technology tools. Common electrical instrumentation classification: There indicating instrument, more instruments, digital instrumentation and detector circuit, recording meter and oscilloscope, expanding range of devices and converters. Electrical measuring instruments according to different targets, divided into ammeter (ammeter), voltmeter (voltmeter), power meter (wattmeter), meter (kWh meter), ohmmeter, etc; works by different instruments into Department of magnetic, electromagnetic system, electric system, induction system and so on; by the different types of measured power into AC table, DC table, AC and DC tables, etc.; according to the nature and the use of different methods divided into fixed device (switch Plate), portable and smart; according to a different level of error into 0.1, 0.2, 0.5, 1.0, 1.5, 2.5 and 5.0 total of seven rating. The smaller the number, the smaller the error meter, high level of accuracy. For pointer instrument, the measuring mechanism is its core; digital instrument, the digital basic table is its core. Lenovo performed by measuring the radial organization can be a basic overview of the instrument at a glance. As indicating instrument to measure core body → → → four five-part series device meter → structure, principles, technical characteristics, the use of notes, on behalf of the like. That leads to the core by indicating instrument measuring mechanism, according to the function of the different components of its parts were divided into five parts unit. Mechanical and electrical equipment installation, Changzhou non-standard machinery manufacturing, steel machine www.lyjngjgc.com nine cattle