Modbus is an application-layer protocol that defines a data unit (ADU) that is independent of the underlying network and can communicate over Ethernet (TCP/IP) or serial links (RS232, RS485, etc.) (Ethernet ADUs and serial ADUs are slightly different). On serial links, the Modbus protocol has two transmission modes – ASCII mode and RTU mode. Among them, ASCII is the abbreviation of "American Standard Code for Information Interchange" in English, and the Chinese translation is "United States National Information Exchange Standard Code"; RTU is the abbreviation of "Remote Terminal Unit" in English, which translates to "Remote Terminal Unit" in Chinese.
In ASCII mode, each 8-bit byte is split into two ASCII characters for sending, such as hexadecimal 0xAF, which will be decomposed into ASCII characters "A" and "F" for sending, and the number of characters sent is doubled compared to RTU. The ASCII mode has the advantage of allowing an interval of up to 1 second between two characters without incurring communication failures, and this mode uses the Longitudinal Redundancy Check (LRC) method to check for errors.
In RTU (Remote Terminal Unit) mode, each byte can transmit two hexadecimal characters, such as hexadecimal 0xAF, and directly send them in hexadecimal 0xAF (binary: 10101111), so its sending density is twice as high as that of ASCII mode. The RTU mode uses cyclic redundancy check (CRC). Most of Banner's products support Modbus communication, the following are the products that support Modbus RTU:
▲The measurement grating supports Modbus RTU communication ▲The pickup indicator supports Modbus RTU communication ▲All wireless products of Banner Engineering support Modbus RTU communication
What is Modbus TCP?
Modbus TCP and Modbus RTU are basically the same, but there are some differences:
The slave address becomes less important and is ignored in most cases. In a sense, the slave address is replaced by an IP address
CRC checksum becomes less important or even negligible. Since the check already exists in the TCP packet, Modbus TCP simply cancels the CRC check in order not to reinvent the wheel.
TCP mode is generated to allow Modbus data to be transmitted smoothly over Ethernet, using TCP502 port. The physical layer, data link layer, network layer, and transport layer of the protocol are all based on the TCP protocol, and the Modbus protocol is only modified and encapsulated in the application layer. After the receiver unpacks the TCP packet, it reobtains the original Modbus frame, parses it according to the Modbus protocol specification, and re-encapsulates the returned packet into the TCP protocol and returns it to the sender. Different from the data format transmitted by serial links, TCP mode removes additional addresses and checks, and adds packet headers. Most of Banner Engineering products support Modbus communication, the following products support Modbus TCP:
▲The security controller supports Modbus TCP communication ▲All Banner engineering vision products support Modbus TCP communication ▲Banner 2D code readers all support Modbus TCP communication ▲Some wireless products of Banner support Modbus TCP communication
|
More on that
|
Problem solving for Banner's QCM series of color sensors
1. Discrete photodiode with color filter
The traditional practice of sensing color is to combine three to four photodiodes on a single chip, with red, green, and blue color filters placed on the surface of the photodiode (usually two blue color filters are combined together to compensate for the ...
|
|
Banner Sensors - Introduction to the features and advantages of fiber optic sensors
High sensitivity
Lightweight and flexible, easy to install and buried
Electrical insulation and chemical stability. Optical fiber itself is a highly insulating and chemically stable substance, which is suitable for harsh environments such as high-voltage isolation and flammable and explosive in power systems and chemical systems
Good security ...
|
|
What are the application areas of Banner Sensors – Laser Displacement Sensors?
1. Scale determination: identification of the orientation of small parts, monitoring of whether there are parts on the conveyor belt, exploration of material stacking and masking, manipulator orientation (east and west center orientation) control, equipment condition detection, equipment orientation exploration (through small holes), liquid level monitoring, thickness measurement, ...
|
|
Banner Sensors – A common term for pressure sensors
Pressure is one of the important parameters in industrial production, and in order to ensure the normal operation of production, it must be monitored and controlled. The following are common terms used when selecting pressure sensors:
Standard press
The magnitude of the pressure expressed by atmospheric pressure is greater than the atmospheric pressure ...
|
|
Banner Sensors - An introduction to the classification of pressure sensors
1. Strain gauge pressure sensor
Strain gauge pressure sensors are sensors that measure pressure primarily by measuring the strain of an elastic element. Depending on the material, strain gauges are divided into metals and semiconductors. When the conductor and the semiconductor material are mechanically deformed, their resistance value will change.
|
|
Banner Sensor - How to install a magnetic scale displacement sensor magnetic tape
1. The magnetic tape can be directly pasted on the surface of the equipment, and the two ends are fixed with screws;
2. The magnetic tape can be directly installed in the reserved groove;
3. The magnetic tape can be pasted in the aluminum alloy protective shell provided by the manufacturer, and then the magnetic ruler can be fastened to the equipment with the mounting bracket.
...
|
|
Banner Sensors – The emitter of a photoelectric sensor has several light sources
1. Red LED – visible light, easy to adjust.
2. Infrared LED – high energy invisible light.
3. Red laser – visible light, its physical properties are ideal for small object detection and large detection ranges.
...
|
|
Banner Sensors – Classification and Advantages and Disadvantages of Infrared Sensors
Infrared sensor is a kind of sensor that uses infrared rays to process data, which has the advantages of high sensitivity, and the infrared sensor can control the operation of the driving device. Infrared sensors are commonly used for non-contact temperature measurement, gas composition analysis and non-destructive testing.
|
|
Banner Engineering launches BSP02 series small PLC upstart
United States Banner Engineering grandly introduces a new generation of high-speed, high-performance BSP02 series programmable logic controller, which is Banner's outstanding masterpiece, the new upstart in small PLC! Compared with the first generation of BSP01, BSP02 has a faster execution speed; More application directives; Larger IO expansion; And support straight ...
|
|
Banner Sensors - An introduction to the classification of fiber optic sensors
According to the modulation form of the light measured object, it can be divided into: intensity modulation type, polarization state type, phase type and frequency type;
According to whether the light interferes or not, it can be divided into: interference type and non-interference type;
Depending on whether it is possible to continuously monitor the measured as the distance increases, it can be divided into ...
|
|
Wiring method for Banner R58 sensor
1. The wiring method of various sensors is basically the same, and the pressure sensor generally has a two-wire system, a three-wire system, a four-wire system, and some five-wire systems;
2. The two-wire system of the pressure sensor is relatively simple, one wire is connected to the positive pole of the power supply, and the other wire is the signal line through the instrument.
|
|
Banner Sensors – Routine maintenance methods for pressure sensors
1. Prevent the debris from being deposited in the catheter and the sensor from coming into contact with corrosive or overheated media.
2. When measuring gas pressure, the pressure intake should be opened at the top of the process pipeline, and the sensor should also be installed in the upper part of the process pipeline, so that the accumulated liquid can be easily injected into the process pipeline.
...
|
|
Banner Sensors – The difference between a level sensor and a level switch, a level controller, a level transmitter, and a level gauge
Liquid level sensors
A liquid level sensor is a common sensor that measures the position of a liquid level, and it is an output that converts the height of the level into an electrical signal. The liquid level sensor is a modular circuit, which has the advantages of acid resistance, moisture resistance, shock resistance, corrosion resistance, etc., and the circuit contains constant current feedback ...
|
|
Banner Sensors – the development trend of smart temperature sensors
The three foundations of modern information technology are information collection (i.e., sensor technology), information transmission (communication technology), and information processing (computer technology). Sensors belong to the cutting-edge products of information technology, especially temperature sensors are widely used in industrial and agricultural production, scientific research and life.
|
|
Banner Sensors – A way to test the quality of pressure sensors
First, the test method of pressure sensor
The test on pressure sensors mainly includes the following aspects:
Resistance test
Output signal test
Overload test
1. Resistance test
The test machines are as follows: power supply, multimeter, ammeter, ...
|
|
How to adjust Banner's sensors
1. Optical adjustment
The factory setting of the sensor is a large range, and this setting is subject to change. Note: Only use your finger to press the button.
2. Set the range (when stationary)
1. Adjust the sensor with a reflector;
2. Press the button for about 3s until two ...
|
|
Banner Sensors – Precautions for the use of grating displacement sensors
1. Add a protective cover as much as possible, and clean up the chips and oil splashed on the ruler in time to strictly prevent any foreign matter from entering the inside of the grating ruler sensor housing.
2. When plugging and unplugging the grating displacement sensor and the plug holder of the digital display, the power should be turned off.
3. For the extension of the dust seal ...
|
|
Banner Sensors – the measuring principle of fiber optic sensors
(1) The principle of physical optical fiber sensor, which uses the sensitivity of optical fiber to environmental changes to convert the input physical quantity into a modulated optical signal. Its working principle is based on the optical modulation effect of optical fibers, that is, the optical fiber's response to external environmental factors, such as temperature, pressure, electric field, ...
|
|
An introduction to the working principle of Banner photoelectric sensors
Photoelectric sensors are controlled by converting changes in light intensity into changes in electrical signals.
In general, photoelectric sensors are composed of three parts, which are divided into: transmitter, receiver and detection circuit.
The transmitter is aimed at the target to emit a beam, and the emitted light ...
|
|
Banner Sensors - Introduction to the characteristics of fiber optic sensors
1. High precision, fast response speed, wide range of linear features, good repeatability of use, high signal-to-noise ratio of detection signal, due to the mass production of optical fiber, low price, can be widely used.
2. The optical fiber is made of dielectric material quartz, which transmits optical signals, so it is safe ...
|
|
Contact
working hours
