The system of EJA transmitter is mainly composed of inductive digital water level sensor, power circuit, signal conditioning circuit, MCU (C8051F020) minimum system, RS-485 interface (MAX485), 4-20mA output (AD421), and PC , The function of network communication can be realized through the monitoring software of the PC upper computer.
The working principle of EJA transmitter is designed according to the idea of imitating biology and applying neural network design idea. The inside of it is also covered with circuit boards of neurons, and the outside is mainly made of plastic insulating materials, which are generally made of rods.The sensor is mainly composed of an ultra-audio generator and a transmitting head to emit detection signals into the water. Several sampling induction element circuits receive the detection signals through the medium water. The signal voltage obtained after detection by the capacitive coupling detection circuit realizes the direct sampling of the water level signal. Digital sampling sensor.Each of its neuron circuits outputs digital signals in the form of switching pulses. After statistics, the switching digital signals are modulated into analog signal currents (non-standard current signals) and output to the signal conditioning circuit for further processing.
The signal conditioning circuit of the EJA transmitter is mainly to convert the non-standard current signal output by the sensor into a voltage signal to prepare for the C8051F020 analog-to-digital conversion. After the analog-to-digital conversion of the single-chip microcomputer, the sensor signal can be converted into a digital signal, and then it can easily store hydrological data, output 4-20mA standard current signal through the electronic furnace AD421, and RS-485 interface output.
Introduction to common professional terms of EJA transmitter
There are professional terms in their own industry, and EJA transmitters are naturally no exception. In EJA transmitters, we often hear many professional names, but many outsiders or people who are not very familiar with EJA transmitters may not know the meaning. To this end, we have listed the most common professional terms about EJA transmitters for everyone to introduce:
1. Absolute error: the difference between the measurement result of the EJA transmitter and the true value, that is, the measured value-true value = absolute error.
2. Quotation error: It is the ratio of the absolute error of the EJA transmitter to the range, expressed as a percentage, that is, absolute error/range×100%=reference error.
3. True value: The true value in the EJA transmitter is the true value of a variable itself.
4. Relative error: The relative error of the EJA transmitter is the ratio of the absolute error to the measured value. The ratio of the commonly used absolute error to the value indicated by the instrument is expressed in percentage, that is, the sum quoted error? Absolute error/indicated value × 100% = Relative error.
The above introduces the common professional terms of EJA transmitters. Only by understanding what the professional terms mean can we communicate well with the people in the industry. Or it can be a good choice when purchasing EJA transmitters.