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Application example one: Apply AnyBus serial gateway to realize Modbus Plus to Profibus conversion. Question raised: Rema Control AB, located in Vasteras, Switzerland, is a well-known provider of automation solutions for sawing and grinding equipment. In one project, the customer requested to upgrade the entire factory to a system composed of Siemens S7 controller and Profibus-DP bus. However, the existing saw processing measurement system still uses an old Modicon PLC and is connected to the Modbus Plus network. This system works well and should be preserved, while other parts of the plant should be upgraded. To this end, Rema Control had to find a solution to access existing Modbus Plus network data through the new Profibus-DP network. Solution planning: Rema Control uses the AnyBus serial gateway to convert data from the Modbus Plus network to the Profibus network in two steps. A Modbus Plus serial gateway acts as an adapter for the Modbus Plus network and performs 32-byte data input and output on the Modbus Plus network. On the Profibus side, the Profibus gateway is used as a Profibus slave station and is also configured for the input and output of 32-byte data. Then apply the RS-422 serial port settings to realize the internal interconnection of the two AnyBus gateways. The Modbus Plus gateway is configured in Modbus RTU master mode and the Profibus gateway is configured in Modbus RTU slave mode on its serial line. Lennart Hedman, head of system integration at Rema Control, said, “The AnyBus gateway helps us solve a difficult customer problem, allowing our customers to integrate existing measurement systems into the new Siemens S7 automation system. The flexible settings of the AnyBus gateway can select some specific data from the Modbus Plus system and easily map these data to Profibus through another gateway." Additional reminder: HMS can currently provide a simpler way to interconnect two local networks. The latest AnyBux-X series products can interconnect any two local networks with almost no settings required. Application example two: Realize communication conversion between RS232 and Profibus in Modbus master control mode. This example shows a motion controller with ModBus RTU serial protocol. AnyBus serial gateway serves as the ModBus master device to read and write data from the motion controller. In the AnyBus serial gateway configuration program command process, the ModBus master device configures its scan list. The AnyBus configuration program defines all ModBus commands, registers, data mapping and timing. Afterwards, the AnyBus serial gateway controls the ModBus communication of the motion controller and selects data for input/output through the built-in Profibus interface. Through this interface, data is transmitted to the Fieldbus master device and its PLC controller via Profibus. In the picture: 1． Equipment serial port output data bytes. 2． AnyBus serial gateway handles the underlying handshake signal and data validity check (CRC) to ensure that the data will not be erroneous. If all data obtained from the serial device is valid, it is stored in the memory of the AnyBus serial gateway itself. If the data is invalid, AnyBus will automatically request the serial device (RS232) to retransmit. This ensures the accuracy of data selected from memory for transmission to the Fieldbus master device. 3． Data bytes taken over by the PLC Fieldbus master. Note that the AnyBus Serial Gateway only sends a portion of the data stream taken over from the serial device. 4． Data bytes taken over from PLC Fieldbus. These bytes are used by the PLC for input/output data from the Fieldbs network. Only the actual data selected from the serial device is stored and processed by the PLC. From the PLC's perspective, the PLC can ignore that the motion controller is actually a serial interface and treat it as having a built-in Profibus interface. If the Profibus in this example is replaced by Ethernet, it can select the data in the Anybus serial gateway memory to read and write based on the SSI script or Java application of the network server, so that the temperature regulator can run online through the network. source: Control Engineering Chinese Website A few years ago, ultrasonic level meters did not have the long-lasting and accurate sensing capabilities. Today, technological advancement has made this function of ultrasonic level meters increasingly powerful. These new technologies make MHZ ultrasonic level meters easier to use, more flexible and less expensive. Compared to traditional ultrasonic sensor designs, these new features * * Expanded its application scope. Today, MHZ brand ultrasonic level meters can help mechanical designers find innovative solutions to reduce costs, improve quality control efficiency, and enhance inspection functions in many industrial fields. And its application in the field of packaging is becoming more and more in-depth. More comprehensive protection Now, MHZ ultrasonic level meter adopts several advanced technologies, allowing it to be used in areas where traditional equipment cannot work.: The ultrasonic level meter uses a protective cover with IP67 and IP69K protection levels and can detect in humid environments (such as bottle washing machines) ； Built-in temperature compensation circuitry compensates for drastic temperature changes that may occur during normal day and night shift operation ； Special coating on sensor surface protects against harmful chemicals ； Advanced filter circuit makes the ultrasonic level meter immune to the influence of factory environmental noise ； New converter design makes it loss-proof * * Enhanced and can be used in unclean environments. More convenient to use·The new generation of ultrasonic level meter is more convenient to use and has the following characteristics: The button is designed on the sensor housing, making it easier to set the far and near sensing range ； Just place the target in front of the sensor and press the button ； The sensor can automatically distinguish the window size and target distance ； The setup is simple and the same ultrasonic level meter can be used in different environments. ·DIP switch programming allows a sensor to be customized for a specific application. Other programmable features include: Response time, output type, analog or discrete, and other special settings for detecting liquid level. ·Ultrasonic level meters typically have multiple outputs contained within a single sensor. A sensor can have two separate discrete outputs, so one sensor can detect two different distances. For other sensors, there are both discrete and analog outputs in the same sensor to allow both measurement and alarm output. These features make the ultrasonic level meter flexible and suitable as an alternative to other sensor technologies. Because ultrasonic level meters are easy to use and flexible in application, they can make a huge contribution to significantly increasing productivity and improving quality in the field of industrial automation. The principle of use of ultrasonic level meter There is a frequency converter in the ultrasonic sensor. When the converter element vibrates, the frequency converter emits inaudible high-frequency sound waves in one direction. If the sound wave hits an object and reflects back, the transducer can receive the echo signal. The sensor determines the distance to the object based on the time between sending out the ultrasonic pulse and returning the echo signal. Typically, the sensor can be set to a distance range via a button. The sensor determines whether there is an object within the range of these settings. For example, when an ultrasonic level meter mounted on the top of a liquid tank or pallet emits sound waves into the interior of a container, the length of time it takes for the echo to return can indicate whether the container is full, empty, or half full. Some ultrasonic level meters use a transmitter and a receiver transducer respectively. This bi-directional mode ultrasonic sensor is suitable for situations where edge detection or faster response times are required, or when used in humid environments. Ultrasonic sensors should be the first choice when detecting transparent objects, liquids, dense materials with any surface (rough, smooth, shiny) and irregular objects. However, ultrasonic level meters are not suitable for high temperature environments or pressure tanks, nor can they be used to detect large foam objects. The following are important things to consider when applying ultrasonic level meters: ·Range and Size The size of the object to be detected directly affects the maximum range of the ultrasonic sensor. The sensor must detect a certain sound level before it can output. Large parts can reflect most of the sound back to the ultrasonic sensor, allowing the sensor to detect the part at its maximum sensing range. Small parts reflect only a smaller portion of the sound, resulting in less sensing range * * Zoom out. ·Objects to be Detected The ideal object for ultrasonic detection should be large, flat, dense, and perpendicular to the front of the transducer. The most difficult objects to detect are those that are small and made of sound-absorbing material (such as foam rubber), or that are at an angle to the transducer. Some difficult-to-detect objects can be detected by having the sensor detect a background surface and then react to a detection target object between the sensor and the background. Detecting liquids is easy if the liquid level is stationary and perpendicular to the sensor surface. If the liquid level fluctuates significantly, the sensor response time can be extended to average the fluctuation changes to obtain more consistent readings. However, ultrasonic level meters cannot accurately detect liquids with foamy surfaces because the foam will deviate from the direction of sound propagation. The reverse ultrasonic mode of the ultrasonic level meter can be used to detect irregularly shaped objects. In reverse ultrasonic mode, the ultrasonic sensor detects a flat background, such as a wall. Anything that passes between the sensor and the wall blocks the sound waves. The sensor detects this interference to identify the presence of the object. ·Vibration, whether from the sensor itself or from nearby machinery, can affect the accuracy of distance measurements. Rubber anti-vibration devices can be used when installing ultrasonic level meters to reduce such problems. Guide rails are also sometimes used to eliminate or * * Reduce component vibration. ·The attenuation sensor is also designed with temperature compensation to accommodate slow changes in ambient temperature. However, it cannot regulate temperature gradients or rapid changes in ambient temperature. ·Sound waves may be reflected by nearby objects such as guide rails or fixed rods. To accurately detect target objects, the effects of nearby sound-reflecting surfaces must be reduced or eliminated. In order to avoid mis-detection of nearby objects, ultrasonic level meters are equipped with LED indicators to instruct operators during installation to ensure correct installation of the sensor and reduce the risk of mis-measurement. New uses In the past, it was difficult and expensive to use ultrasonic level meters in some areas. Now, due to the reduced cost and ease of use, mechanical designers have gradually begun to use ultrasonic sensors in these areas. In industrial applications, ultrasonic level meters can be used to detect liquid levels, detect transparent objects and materials, control tension, and measure distances. Application industries that use ultrasonic level meters include packaging, bottling, material handling, and the automotive industry. Here are some examples of uses: Used in bottling plants to inspect bottles ； Used in food processing plants to detect and control liquid levels in liquid tanks ； Controlling the material transport speed on the packaging line by monitoring the tension between two rollers ； Inspect pins on car engine blocks. Today, the industrial uses of ultrasonic level meters are rapidly expanding. What was once a costly and unreliable technology is now easy to use and affordable. Ultrasonic level meters are now routinely used in process monitoring to improve product quality, detect defects, determine presence, and other aspects. These sensors also increase productivity by reducing scrap generated by damaged parts and the resulting downtime. The technology also continues to develop new products along this direction. At present, how to make all walks of life realize the application potential of ultrasonic level meters in manufacturing is a major challenge we face, including in aspects such as quality control, process control and inspection.