subject: The Working Principle Of Intelligent Instruments, Characteristics And Development Trends - Equipment [print this page] The emergence of intelligent machines, which greatly expanded the application of traditional instruments. Intelligent instrument with its small volume, strong function, low power consumption advantage, quickly in the household appliances, research institutes and industrial enterprises have been widely used.
1. The working principle of intelligent machines
Sensors pick up information and the measured parameters into electrical signals, interference is removed by the filter into the multi-channel analog switches; by the MCU by way analog switch to the strobe signal input channels one by one into the programmable gain amplifier, amplified signal by the A / D converter into a corresponding pulse signal into the microcomputer; microcomputer based instrument for the corresponding initial set of data operations and processing (such as non-linear correction, etc.); operation results be converted to the corresponding data display and printing; while MCU operation results are stored in the chip FlashROM (Flash Memory), or E? 2PROM (electrically erasable memory) set the parameters of the comparison operation, According to calculation results and control requirements, the corresponding output control signals (such as alarm trigger, relay contacts, etc.). In addition, intelligent instruments can also be composed of PC, distributed control system, the lower position by the microcontroller as a measuring signal and data collected through the serial communication of information transmitted to the host computer?? PC machine, the overall management of PC machines.
2. Intelligent Instrument Features With the continuous development of microelectronic technology, integrates a CPU, memory, timer / counter, parallel and serial interface, watchdog, preamplifier or A / D, D / A converter circuit in a VLSI chip-chip (ie, SCM) emerged. To the main microcontroller, computer technology and measurement control technology together, forming the so-called "Intelligent Measurement and Control System", which is intelligent instruments.
Compared with traditional instrumentation, intelligent instruments has the following features:
automation. Instruments such as keyboard scan the entire measurement process, range selection, switch start closed, data collection, transmission and processing, and display print and so on with a single chip, or micro-controller to control the operation, to achieve the full automation of measurement process.
with self-test features, including automatic zero adjustment, automatic fault with the state test, automatic calibration, self diagnosis and auto-range conversion. Smart meters can automatically detect the fault location and even failure. This self-test can be run at startup equipment, but also can run in the instrument, which greatly facilitate the maintenance of the instrument.
with data processing, which is one of the main advantages of intelligent instruments. As a result of a single chip smart devices or micro-controller, so many of the original can not be solved by hardware logic or can not solve the problem, can now use the software very flexible solution. For example, the traditional digital multimeter can only measure resistivity, AC and DC voltage, current, etc., and intelligent digital multimeter is not only able to carry out such measurements, but also with the measurement results, such as zero shift, taking on average, demand extreme, statistics analysis of complex data processing functions, not only to heavy users of data processing from the liberation, but also effectively increase the measurement accuracy of the instrument.
ability to have a friendly man-machine dialogue. Intelligent instruments using the keyboard instead of the traditional instruments in the switch, the operator simply by typing the command, you can achieve some kind of measurement. At the same time, intelligent instruments, through the operation of the instrument display, work status and processing results of the survey data tell the operator, makes the operation more convenient and intuitive.
operation with the ability to be programmed. General intelligence apparatus are equipped with GPIB, RS232C, RS485 and other standard communication interfaces, can be easily and PC machines and other equipment needed for the user with the composition of multiple functions of the automatic measurement system to perform more complex testing tasks.
3. Overview of Intelligent Instrument
80 years, microprocessors are used in instruments, keyboard instruments began to move toward the front direction of the development of measurement systems often by IEEE? 488 bus connection.
