Working principle of weighing transmitter

Working principle of weighing transmitter

1:Working principle of weighing transmitter:

The weighing transmitter load cell amplifier can realize stable, reliable, and high-precision industrial weighing. It converts the weak signal (mV level) output by the load cell into a readable weight signal by amplifying and converting it into a readable weight signal. The results can be output via Ethernet, serial bus, Bluetooth, etc., and various specified industry standard signals can be converted and output according to requirements for other equipment to use.

The weighing transmitter load cell amplifier adopts a high-performance weight transmitter with a guide rail installation method, which is used in conjunction with a strain gauge sensor. The weighing transmitter load cell amplifier can be used to convert the connected weighing sensor signal into a stable signal that can be used by the PLC system or PC. The weighing transmitter is suitable for applications that require local display or use the panel for parameter setting. The parameter setting and calibration of the instrument can be carried out using the buttons on the panel, or by using the "deltaCOM" software based on the Windows environment. All the setting parameters can be stored in the computer, and the parameters can be downloaded from the computer when the transmitter load cell amplifier is replaced. This requires the use of the full version of the deltaCOM software. The weighing transmitter load cell amplifier provides two relay-type output nodes with a response time of less than 20 milliseconds, which is particularly suitable for high-precision weight setpoint control applications. The core of the weighing transmitter adopts the digital A/D converter designed by NOBEL Company to provide stable, accurate and fast signal conversion. It can communicate with the PC/PLC system through the standard RS-485 communication port using MODBUS RTU protocol. The field bus communication function can also be realized by using the module.

2:Weighing transmitter load cell amplifier adjustment method

2.1: Preparation for debugging

The power supply positive, signal positive, signal negative, and power negative of the sensor are respectively connected to E+, S+, S-, E- of the amplifier. The power supply voltage of the amplifier is 24V/0. The power supply is connected to the load cell amplifier's 24V (pin 10), and the power supply is negative to the load cell amplifier's GND (pin 7).

2.2: Voltage output adjustment

2.2.1. Make the sensor no load, adjust the voltage output zero potentiometer RW1, so that the output voltage (between VO and GND) is 0V.

2.2.2. Put a weight of a certain weight (the weight of the weight is represented by A, and the full range of the sensor is represented by B. The weight of the weight should be greater than 30% of the sensor range), and adjust the voltage full-scale potentiometer RW2 so that the output voltage is A/B*5 (voltage output 0~5V) or A/B*10 (voltage output 0~10V). For example, if the sensor is 8kg and the weight is 4kg, the output voltage should be 4/8*10=5V.

2.2.3. Use weights of different weights to verify the output (the weight of the weight is represented by A, and the full range of the sensor is represented by B), and the output voltage should be A/B*5 (voltage output 0~5V) or A/B*10 (Voltage output 0~10V).

2.3Current output adjustment

2.3.1. Make the sensor no load, adjust the voltage output zero potentiometer RW1, so that the output voltage (between VO and GND) is 0V.

2.3.2. Make the sensor load cell no load, adjust the current output zero potentiometer RW4 so that the output current (between IO and GND) is 4mA.

2.3.3.Put a weight of a certain weight (the weight of the weight is represented by A, and the full range of the sensor is represented by B. The weight of the weight should be greater than 30% of the sensor range), and adjust the current full-scale potentiometer RW3 so that the output current is (4+16*A/B) mA. For example, if the sensor is 8kg and the weight is 4kg, the output current should be 4+16*4/8 = 12mA.

2.3.4.Take off the weight, if it is not 4mA at no load. Repeat the process 2 and 3. Until the no-load is 4mA, put a weight of A (the sensor range is B) and the output current is (4+16*A/B) mA.

2.3.5.Use different weights to verify the output (the weight of the weight is represented by A, and the full range of the sensor is represented by B), and the output current should be (4+16*A/B) mA.

Note: No load on the sensor means that there is no heavy object on the sensor. If there is a weighing pan, and the weighing pan is heavy (greater than 10% of the full scale of the sensor), the zero point may not be adjusted to 4mA.

3:Weighing transmitter load cell amplifier purpose:

The weighing transmitter load cell amplifier is a multi-purpose weight signal conversion device with serial digital signal output, small size, light weight, and reliable performance. It is suitable for various applications of resistance strain type load cell such as tension, tension, pressure measurement, weighing type material level, hopper scale, balance scale, crane scale, tension and compression testing machine. At the same time, it can meet the digital upgrade of analog sensors, and is widely used in industrial weighing and force measurement in various industries such as food, light industry, metallurgy, building materials, chemical industry, non-ferrous metals, energy, machinery and so on.