\nSensor: A sensor/device that detects or measures a physical property and records, displays, or otherwise responds to it.
\n
\nTransducer: It is a converter/device that converts the changes of a physical quantity such as pressure or brightness into an electrical signal and vice versa.
\nTransmitter: As described in the article “What is a transmitter?” We said that the transmitter is a set of equipment used to produce and transmit electromagnetic waves carrying messages or signals, especially radio or television waves. Such as PM-LT11A
PM-LT11A (Weight Transmitter)
Now that we are familiar with the meaning of each, let’s take a look at the application of each in industrial automation and precision instruments:
\nA sensor is a device that senses the desired physical changes and produces an output signal according to the changes. Such as RTD temperature sensors, thermocouples and strain gauges.
\nTransducer or converter is a tool that converts one type of energy into another type, in the field of instrumentation, it is the output of an electrical signal. In fact, it measures pressure, power, temperature, etc. and creates an electrical signal accordingly.
\nWith the definitions and examples above, it can be said that all sensors are a subset of transducers, but not all transducers are sensors.
\nTo better understand the basic explanation of the transducer, a pressure sensor converts mechanical energy into electrical energy, so it can be classified as a transducer, and a speaker converts electrical energy into mechanical energy (sound), so it can be said to be a transducer, but it is not a sensor.
And the transmitter:
\nThe transmitter is used as a measuring and intermediate signal conversion device. In fact, it amplifies and transforms the signal received from the sensor. Then it produces the output signal with the ability to transfer to the control or display device.
\nIn other words, a transmitter is an intermediate signal converting device that is usually used to measure physical parameters such as pressure, temperature, level, current, etc.
\nConsequently, the difference between sensors, transducers and transmitters is in the type of signal they convert and also in their application in industrial automation and instrumentation. Sensors are used to detect and measure desired physical changes. Transducers are used to convert physical changes into electrical signals. And the transmitters are used to amplify and convert the intermediate signal into a signal that can be transferred to the control device (PLC) or display (HMI).
To check the difference between sensor, transducer and transmitter, we must first check the meaning of each of them.
\nSensor: A sensor/device that detects or measures a physical property and records, displays, or otherwise responds to it.
\nTransducer: It is a converter/device that converts the changes of a physical quantity such as pressure or brightness into an electrical signal and vice versa.
\nTransmitter: a transmitter/set of equipment used to generate and transmit electromagnetic waves carrying messages or signals, especially radio or television waves.
Transmitter literally means sender, in the world of communication, a transmitter is a device that sends radio waves through an antenna.
\nIn the world of process control (industrial automation), a transmitter is a device that converts a signal produced by a sensor into an instrument signal that represents a parameter being measured and controlled.
\nTypically, the transmitter output signal is a standard analog value such as 0 to 10 volts or 4 to 20 mA.
\nIn process control, the output signal of the transmitter is equal to 0 to 100% of the physical parameter sensed in the sensor.
\nIn a weighing system, the weight value is a physical parameter that we intend to measure, the load cell is the sensor, the output signal of the load cell has a non-standard value, the weight transmitter converts this signal to standard values and sends it to the controller (plc or pc or…) sends.
\nFor example, a weight transmitter with a current output of 4 to 20 mA to which a load cell with a capacity of 200 kg is connected will produce 4 to 20 mA per 0 to 200 kg (0 to 100%).
\nThere are other types of transmitters that transmit the processed value digitally, such as transmitters that have Modbus, hart or ethernet communication capabilities. In these transmitters, in addition to the transmission of the process value (pv), more parameters can also be transmitted.
\nNow that we are familiar with the transmitter and sensor, let’s take a look at the location of the transmitter (for example, Pars Mega weight transmitter model PM-LTD11A) in a process control system.
\nAs mentioned earlier, the transmitter converts the signal received from the sensor into process value (pv), which represents the physical measured variable.
\nA controller is a device that monitors the difference between the process variable (pv) and the set point (sp).
\nThen, according to the result of comparing pv and sp, it determines what action to take and finally produces a digital or analog signal at its output. Controllers are usually a plc.
\nTransmitter literally means sender, in the world of communication, a transmitter is a device that sends radio waves through an antenna.
\nIn the world of process control (industrial automation), a transmitter is a device that converts a signal produced by a sensor into an instrument signal that represents a parameter being measured and controlled.
\n",seoDescription:"Transmitter-Parsmega-What is transmitter-Weight Transmitter-Loadcell-Indicator",link:"/articles/post/what-is-a-transmitter",publishDate:"2023-04-05T07:34:21",seoJsonLd:_},{id:637,slug:"the-difference-between-4-and-6-wire-load-cells",title:"The Difference Between 4 and 6 Wire Load Cells",content:'Depending on the model, the load cells have 4 or 6 wires with a wire shield. 6 wire types in addition to power +, power -, signal + and signal – terminals (Ext+, Ext-, Sig+, Sig-) have two other wires, sense + and sense – (Sen+, Sen-) or reference+ and reference- are.
\nThe resistance of electric wires depends on factors such as temperature and length. Considering this, it can be said that changes in temperature and length can cause changes in the voltage drop on the wire, which the 6-wire system allows to compensate for these changes.
\n4-wire load cells are sensitive to thermal variations and are calibrated with standard cable lengths. For this reason, it is recommended not to shorten the cable length of 4-wire load cells; In the case of weighing systems, displays and transmitters with 6-wire input and junction box, it is recommended to use 6-wire load cells to compensate for the voltage drop on the cable between the display and the junction box.
\nIf you are using a weight display or a weight transmitter with 4-wire capability, it is recommended to use a shielded cable with a suitable cross-section (at least 1 mm), so that the voltage drop will be as low as possible.
\nIn case of using 6-wire load cell, there is no need to observe these things.
\nThe sense or reference wires are connected to the sense terminals (Sen+ and Sen-) of the display and by measuring the actual voltage that reaches the load cell, it increases the accuracy of weight calculations.
\nFor this reason, using 6-wire load cells is preferable to 4-wire. Also, by increasing or decreasing the length of the wire, the accuracy of the load cell does not change.
Depending on the model, the load cells have 4 or 6 wires with a wire shield. 6 wire types in addition to power +, power -, signal + and signal – terminals (Ext+, Ext-, Sig+, Sig-) have two other wires, sense + and sense – (Sen+, Sen-) or reference+ and reference- are.
\nThe resistance of electric wires depends on factors such as temperature and length. Considering this, it can be said that changes in temperature and length can cause changes in the voltage drop on the wire, which the 6-wire system allows to compensate for these changes.
Wide range of port 485 baud rate (from 2400 to 230400)
\nModule status LED Indicator
\n10-bit Analog to Digital converter
\n1 CT input
\nWorking temperature range: -30 ~ +75 degrees Celsius
\nRS485 serial communication with MODBUS protocol support
\nCurrent and voltage analog output
\n","Connector","1","230 VAC","7Segment","walled","compact plastic","24-bit analog to digital converter
\n4 digit display with scaling capability
\nModbus RS485 serial communication
\nWith inputs: 4~20ma, 0~20ma, 0~5V, 0~10V
\nThe possibility of connecting a resistance ruler
\nAbility to connect to PLC, HMI and computer
\n","https://enpanel.parsmega.com/wp-content/uploads/2023/04/PM-AD11.jpg","https://enpanel.parsmega.com/wp-content/uploads/2023/04/PM-AD11-Usermanual.pdf","PM-AD11","Most of the transmitters used in industrial automation have analog output, and many times it is necessary to show the parameters measured by the transmitters to the user in addition to being transferred to the processing unit. The PM-AD11 analog indicator has a 16-bit analog input that accepts 0-20mA, 4-20ma, 0-5V, 0-10V analog signals as input and displays it using a 4-digit display. It also provides the possibility to scale the input. RS485 port can be very useful for transferring information to HMI or PLC. This analog indicator signal has 3 output relays, which can be programmed for different applications.
\nAnother unique feature of the PM-AD11 analog display is the ability to connect a resistance ruler.
\n","PM-AD11-Parsmega-Analog Indicator-Weight Indicator-Weight Controller","5 ingredients mixer program (manual emptying)
\n4 ingredients mixer program (automatic draining)
\nTanker and silo emptying program
\n5 relay output
\n3 digital inputs
\nTwo rows of 7-segment displays
\nDisplays the status of the outputs
\n4 buttons to set menus
\nRS485 and RS232 ports
\n24-bit analog to digital converter
\nIt has a 16-bit analog output
\nAbility to connect to PLC and HMI
\n","https://enpanel.parsmega.com/wp-content/uploads/2023/04/WI01.jpg","PM-WI01 is a weight indicator with several programmable programs for a variety of weighing systems. By using two rows of 6-digit 7-segment type displays, this indicator provides the possibility of displaying various parameters in addition to ease of settings. In this weight controller, like other Pars Mega indicators, an ADC with 24-bit accuracy has been used, which has created an extraordinary resolution of 1:100,000.
\n","کنترلر وزن-PM_WI01-ParsMega-کنترلر-وزن-Weight_Indicator-Indicator-Weight Controller","https://enpanel.parsmega.com/wp-content/uploads/2023/04/PM-CTR11A.jpg","https://enpanel.parsmega.com/wp-content/uploads/2023/04/PM-CTR11A-Usermanual-1.pdf","PM-CTR11A Manual","PM-CTR11A is a current transformer converter to standard analog signal and digital value. This module is capable of measuring currents with different waveforms (waveforms with different cutting types) by using a True RMS converter chip. It is for connecting to a current transformer with an output of 5 amps. This module has the ability to connect to the computer and control equipment such as (HMI and PLC) through the RS485 serial port. It also has the ability to convert the output current of the current transformer to the following standard analog signals.
\n0-10 volts
\n0-5V
\n0-20 mA
\n4-20 mA
PM-CT11A is a current transformer converter to standard analog signal and digital value. This module is by default for connecting to current transformer with 5 amp output. This module has the ability to connect to the computer and control equipment such as (HMI and PLC) through the RS485 serial port. It also has the ability to convert the output current of the current transformer to the following standard analog signals.
\n0-10 volts
\n0-5V
\n0-20 mA
\n4-20 mA
LED display panel with large dimensions
\nRS485 serial communication
\nRS232 serial communication
\nThe possibility of specifying different weight units
\nSupport for common displays in the market
\nParsMega, Keli, Laumas, Yaohua
\n","-99999~999999","https://enpanel.parsmega.com/wp-content/uploads/2021/06/PM-RD01-1.jpg","https://enpanel.parsmega.com/wp-content/uploads/2021/06/PM-RD01.jpg","https://enpanel.parsmega.com/wp-content/uploads/2023/05/PM-RD01-Usermanual.pdf","PM-RD01 Manual","The remote display is used to display weight information in large dimensions in open environments and long distances. Pars Mega model PM-RD01 remote display is designed using an LED panel, which enables the display of 6 digits with high resolution and large dimensions. .
\nIn addition to being connected to Pars Mega products, PM-RD01 display can be connected to common weight indicators.
\nThe ability to connect via RS485 and RS232 and various software features have turned this model into a complete display.
\n","By connecting to the main weight indicator, the remote display provide the possibility of displaying the weight in larger dimensions. The PM-RD01 remote display provides the possibility of displaying the weight in the dimensions of 64 x 16 cm by using the LED panel.\r\nIt also supports common indicator protocols.","8 isolated inputs
\n8 Isolated Relay output(5 Amp)
\nLED display of input and output status
\nRS485 serial communication
\nAbility to connect to PLC, HMI and computer
\nHas a power indicator LED
\nHas a LED indicator for performance (Status)
\n",0,"https://enpanel.parsmega.com/wp-content/uploads/2021/06/PM-RIO18L-2.jpg","https://enpanel.parsmega.com/wp-content/uploads/2023/04/PM-RIO18-Usermanual.pdf","PM-RIO18L Manual",'No need for a separate power supply (powered via USB)
\nIsolated electric circuit between USB and bus 485 up to ±15KV ESD
\nData sending and receiving rate up to 3Mbps
\nWith screw terminal for RS485
\nIt has an LED display for sending, receiving and feeding
\n",0,"https://enpanel.parsmega.com/wp-content/uploads/2021/06/PM-US01-ISO.jpg","PM-US01 is a USB to RS485 converter. which enables the exchange of information with RS485 networks through the USB port. In this way, by connecting the converter to the computer, a COM port is added to the system, which provides the possibility of sending and receiving information.
\n","This module is used to convert USB port to RS485 industrial port. RS485 is used in most industrial equipment such as transmitters.\r\nThe isolation of this converter helps a lot in the stability and speed of data transfer.","Can be installed on the board
\nTwo rows of 7Segment displays with the ability to display various parameters
\nAnalog output 4~20mA and 0~10V
\nRS485 port
\nModbus RTU and Modbus ASCII protocol
\n3 digital inputs and 5 relay outputs
\n","https://enpanel.parsmega.com/wp-content/uploads/2021/03/PM-LD01.jpg",'This weight indicator is an evolved version of the PM-LD01 model, and an advanced 24-bit ADC is also used in this indicator. In addition, with the help of designing hardware and software filters, it has been able to achieve resolution of 1:100,000.
\nThe PM-LD01A indicator also has the ability to convert the weight value into standard analog signals that can be used in PLC. The analog output accuracy of this indicator is 16 bits, which is acceptable accuracy in weighing systems.
\n',"Weight indicator PM-LD01A is a full-featured weight indicator, accuracy 1:100,000, using 24-bit ADC chip, 5 relay outputs, 4 application programs for outputs, 3 programmable inputs, and analog output with 16-bit accuracy of voltage and current. PM-LD01A is a unique weight indicator.",0,"0-10V; 0-5V; 0-20mA; 4-20mA","https://enpanel.parsmega.com/wp-content/uploads/2023/04/PM-LD01-UserManual.pdf","PM-LD01A Manual","The ability to support a variety of network settings
\nIt has RS232 and RS485 ports
\nIt has a segment 7 display with a character height of 5 cm
\nSupply voltage 12 to 36 volts (220 volts if ordered)
\nIt has a frame with IP68 degree of protection
\nThe working temperature range is -30 ~ +75 degrees Celsius
\nRTU/ASCII Modbus support
\n","https://enpanel.parsmega.com/wp-content/uploads/2021/06/PM-RD02-1.jpg","https://enpanel.parsmega.com/wp-content/uploads/2021/06/Capture.jpg","https://enpanel.parsmega.com/wp-content/uploads/2023/05/PM-RD02-Usermanual.pdf","PM-RD02 Manual","PM-RD02 is a remote display that supports Modbus RTU/ASCII protocol and has the ability to connect to all types of HMI, PLC and computer, and also has the ability to connect to weight indicators.
\nremote displays are always used next to a main indicator and receive and display information from it. Secondary indicators often have larger dimensions than the main indicator. In fact, one of their uses is to display information in larger dimensions.
\nIn addition to connecting to common market indicators such as ParsMega, Lamas, Kelly, Yahua, PM-RD02 has also provided the possibility to be used as a Modbus indicator, in this way it can be connected to all kinds of PLC, HMI and computer.
\nIP68 physical protection enables this indicator to work easily in all environmental conditions with high humidity and pollution.
\n","Remote displays are mostly used next to indicators like the weight indicator and display the values calculated by them in larger dimensions, the PM-RD02 display also has the ability to display the values sent from Modbus. This ability makes this module have many different applications. The suitable dimensions and waterproofness of this indicator enable its installation in all environments.",'