Interface load cell

We offer a full line of low-cost Data Acquisition and Control modules which can be daisy chained together and connected to a single communications port of a PC or Laptop. Our HMI Software as pictured above is specifically designed to communicate with these modules and can be set up very quickly and easily by the novice with little or no programming skills.

Advanced programmers can utilize the power of this software by writing complex scripts, conditional statements, and control logic that will run in the background. Easy 2-point calibration to set zero and full scale readings.

Can also include a combination of digital input channels, digital output channels, analog output channels, and thermocouple input channels. Load Cell Interface Definition A typical load cell is used to measure weight, force, pressure, or tension, and is commonly used in an industrial setting for various functions.

For example, it can be used on a production line to determine the quantity of product pieces being added to a container, or used in a testing application to determine the amount of force a product can withstand before failure. These load cells use a wheatstone bridge to convert the pressure to a voltage which can be measured by a load cell interface module such as what's shown above.

interface load cell

These modules read the voltage and convert it to a digital format which can be delivered to a host computer via the USB or RS port. These modules can also be calibrated by the user to convert the readings to any engineering units of choice so that the number shown on the computer screen directly represents the information of interest.

The DAQ modules are offered in two different footprints as shown above, enclosed in a case with full electrical isolation, or a non-isolated bare OEM circuit board. Both of these versions are stackable and can be mixed together if desired. Carrier Sense CS is the monitoring of the data bus for a period of inactivity before a DAQ module is allowed to begin its own transmission.

Multiple Access MA means that once the bus is free, every DAQ module in the network has an equal opportunity to transmit a frame. And Collision Detection CD uses non destructive bit wise arbitration to preserve the integrity of a data frame when two or more DAQ modules try to transmit at the exact same time. And since the data frame that wins arbitration remains intact during a collision, there is no additional communications delay when a collision occurs no matter how often it happens.

Host Communications To communicate with the DAQ modules, commands are sent to the individual units by including a header character at the beginning the address so that it can be routed to the appropriate unit. If using multiple units connected together, the DIP switch for each unit should be set to a different position so that it will be assigned a different header character. Each DAQ module has its own command set used to configure it, operate the functions, and to read data from it.

These commands are listed in the product data sheets. ModCom has a communications dialog box which can be used to transmit individual commands to the DAQ modules and see the data coming back. This is helpful in learning the style of the command-set protocol and testing the hardware that's attached to the DAQ module. It is highly recommended that this testing be done prior to setting up any complex control programs.

For each input channel there are three factory calibrated modes which will return the results listed in voltage, and two user programmable custom modes which will return the results listed in any direct linear engineering units of choice. To calibrate a custom mode, first set the zero point, then either apply a known stimulus and tell the module what number you want to see on the computer screen, or tell the module what exact voltage you want to represent one unit of measurement. The gain and offset for this particular input channel will be automatically re-calibrated to meet this criteria.

For more information, see "User Programmable Modes" shown below. Input Channel Scanning During normal operation, the Load Cell Interface module continuously scans all channels in the background regardless of whether or not they are being polled by the host. At any time a READ command is issued, the 8 samples associated with that particular channel are average together and the results will be the data which is returned to the host.

This 8 times averaging smoothes out the readings and reduces the jitter shown on the computer screen. User Programmable Modes The Load Cell Interface modules incorporate a bit floating point math routine which provides data conversions using calibration coefficients stored in non volatile memory. Each of the modes selected with the MODE command has its own set of calibration coefficients.

There are two modes which can be programmed by the user to display the results of each READ command in the linear engineering units preferred.

Mode 5 has a range of SPAN can be used if a known output reading can be generated by the load cell. Sensor manufacturers often include a shunt resistor for this purpose and when attached to the sensor's bridge, will cause it to output a voltage which represents a specific reading. Applying a known weight to a load cell also works well. After setting up the sensor so that it outputs the known reading, transmit the SPAN command with the value field containing the reading that should be displayed on the computer screen.

Multiplying the value by multiples of 10 will increase the resolution.This chip is designed for high-precision electronic scale and design, has two analog input channels, programmable gain of integrated amplifier. The input circuit can be configured to provide a bridge voltage electrical bridge such as pressure, load sensor model is an ideal high-precision, low-cost sampling front-end module.

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interface load cell

Communicating with the Balance Module requires a driver for the HX sensor. The simplest way to install the driver is to download the HX library. Refer the image above for your references. Download the sample source code below, open and upload this sample source code into your Arduino IDE.

Load Cells

NOTE : You can change your calibration factor before uploading the code OR you can adjust it later in the serial monitor box since the code allow you to add and substract the value of calibration factor. When you has succesfully uploaded the sample source code into your Arduino Uno Board. Open Serial Monitor and it will show u as shown in the picture above.

You have to calibrate only once for each load cell. We did not use the correct calibration factor. You have to set your own calibration factor for your load cell. Check on this video and tutorial to learn on how to set the calibration factor for load cells. Remember that each load cell with different weight ie.

Thus, you will have to set calibration factor for each load cell with different weight. Thanks for the instructable - it has helped me get going quickly with my project using the HX One thing though: I was slowed down by the use of the.

I don't have any program on my PC that extracts that type of file. This is just a few dozen lines of code, so I don't understand why it would need to be compressed. Simply inserting the text so someone could copy and paste would be easiest. Next easiest would be to make the uncompressed Arduino. Reply 7 weeks ago.Request a Quote. Request a CAD File. Please login or register for Product Pricing and File Access. If you need to measure 1 pound 4. With many variants and configurations our fatigue-rated load cells provide up to million fully rendered cycles.

The gaged sensors in every load cell are individually inspected and tested, and certified to meet our rigid standards. See datasheet for available models, additional capacities, connectors, options, and accessories.

For a free downloadable CAD viewer, click here. For sales, service, or support, please call or contact us. This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are as essential for the working of basic functionalities of the website.

We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience. Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website.

These cookies do not store any personal information. Capacities from lbf to 50K lbf 1. Options Available for 2nd, 3rd Bridge and Overload Protection.

Models, and are available.Tovey Engineering manufactures force transducers and force calibration systems with industry leading accuracy and reliability. We focus exclusively on test measurements, materials testing, and metrology markets, offering a variety of standard products, special transducer designs. Our standard force products are used for research and development, material testing, creep and fatigue testing, component testing, sub-assembly testing and final assembly testing.

A range of product measurement uncertainties are available to meet everyday requirements up through high performance applications. Tovey Engineering manufactures force transducers from 1 to 1 million lbf with industry leading accuracy and reliability. Tovey offers a variety of column-style and shear web load cells for high capacity applications. Products can be readily customized to meet special customer requirements.

Special transducers conforming to specific customer configuration requirements have met stringent creep, non-linearity, hysteresis, moment sensitivity, and temperature sensitivity. On different special projects, Tovey transducers have achieved creep of Tovey offers both automated transfer-standard and deadweight force calibration systems. TEI systems have been engineered over the last 20 years to achieve very low uncertainties with maximum ease-of-use for cal lab personnel. Automated system measurement uncertainties are as low as 0.

Tovey also manufactures custom calibration systems for advanced transducer calibration. These include multi-axis load cell calibrators, systems for oversized load cells, systems permitting environmental control, and other applications. Using the same high quality load frames that are machined and built for customers, along with some of the most stable and accurate instrumentation available, Tovey Engineering is able to perform consistent load cell force calibrations.

Tovey Engineering offers accredited force transducer calibration from 1 to 1 million lbf. Tovey is the leading supplier of automated force calibration systems to the US military, with systems achieving total measurement uncertainty of 0. Above: Compression style transfer standard systems for a military customer, part of a project involving 31 systems. Tovey Engineering offers strain gaging services to the industry including engineering the project, installing strain gages, wiring the circuit, installing appropriate protective coatings, and testing for function.

Tovey will perform services in our facility when possible or do field installations when necessary. The same standards and methods used for Tovey transducer manufacture are used in component gaging, resulting in high quality, reliable strain gage installations. Tovey Engineering calibrates instrumentation using high accuracy and high precision reference standards with direct traceability to NIST.

Proper characterization of calibration transfer errors, as well as comparison calibrations with NIST and other metrology labs at all levels, allows Tovey Engineering to perform uncompromising and repeatable calibrations that can be trusted. Tovey manufactures all load cell and system components in-house, for close quality control and to meet exacting standards and short lead times. High performance special transducer designs can be rapidly prototyped with integrated design, finite element analysis, and manufacturing softwarethen tested and verified at a high level.

All Tovey load cell flexures, machined system components, adapters and similar parts are machined in-house in the machine center. Tovey transducers incorporate significant know-how related to strain gage application that is critical to part performance. Tovey Engineering is located in sunny Phoenix, Arizona.

Great for outdoor activities and high performance transducers. On different special projects, Tovey transducers have achieved creep of. Tovey offers both automated transfer-standard and deadweight force calibration systems. Tovey Engineering offers accredited torque calibration from 1 tolbf-in. Above: Tovey instrumenting the cruise stage of the Mars Rover.

All Rights Reserved U.Sensors are devices usually electro-mechanical which help us measure a physical parameter such as temperature, pressure, force, acceleration etc. Most sensors require power to be provided to a sensing element and an electrical signal is then generated after the measurement. A load cell is a sensor or a transducer that converts a load or force acting on it into an electronic signal.

This electronic signal can be a voltage change, current change or frequency change depending on the type of load cell and circuitry used.

There are many different kinds of load cells. We offer resistive load cells and capacitive load cells. Resistive load cells work on the principle of piezo-resistivity. This change in resistance leads to a change in output voltage when a input voltage is applied. Capacitive load cells work on the principle of change of capacitance which is the ability of a system to hold a certain amount of charge when a voltage is applied to it.

For common parallel plate capacitors, the capacitance is directly proportional to the amount of overlap of the plates and the dielectric between the plates and inversely proportional to the gap between the plates.

A load cell is made by using an elastic member with very highly repeatable deflection pattern to which a number of strain gauges are attached. In this particular load cell shown to the right, there are a total of four strain gauges that are bonded to the upper and lower surfaces of the load cell.

When the load is applied to the body of a resistive load cell as shown above, the elastic member, deflects as shown and creates a strain at those locations due to the stress applied. As a result, two of the strain gauges are in compression, whereas the other two are in tension. The four strain gauges are configured in a Wheatstone Bridge configuration with four separate resistors connected as shown in what is called a Wheatstone Bridge Network.

An excitation voltage - usually 10V is applied to one set of corners and the voltage difference is measured between the other two corners. At equilibrium with no applied load, the voltage output is zero or very close to zero when the four resistors are closely matched in value.


That is why it is referred to as a balanced bridge circuit. When the metallic member to which the strain gauges are attached, is stressed by the application of a force, the resulting strain - leads to a change in resistance in one or more of the resistors. This change in resistance results in a change in output voltage. This small change in output voltage usually about 20 mVolt of total change in response to full load can be measured and digitized after careful amplification of the small milli-volt level signals to a higher amplitude V or V signal.

These load cells have been in use for many decades now, and can provide very accurate readings but require many tedious steps during the manufacturing process. Resistive Load cells come in various shapes and sizes to meet diverse application needs. Here we show you a few common types:. The millivolt output is not large enough to be measured accurately by an average voltmeter or DMM. One needs to amplify the signal carefully to obtain a signal large enough to be measured with a voltmeter or to be input into a typical PLC or Micro-controller that has a Analog to Digital Converter.

In order to amplify the signal, we offer an analog load cell signal conditioner called AI Once the output signal is amplified to a known 0. Once the output signal has been amplified, one can calibrate the load cell by applying known loads and calculating a linear equation that best fits the curve. Loadstar Sensors uses NIST traceable equipment to calibrate sensors and provides a calibration certificate with all its products.Our facility produces them in several shapes and sizes.

This helps us produce the most accurate and reliable data possible. Therefore, with the wide variety of load cell specs we have in stock, most customers are able to use an off-the-shelf application. However, our engineers can also work with you to design a custom load cell to fit your exact needs.

Contact us so that we can help you find a solution that fits your needs. Download or Print the Load Cell Brochure. For sales, service, or support, please call or contact us. This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are as essential for the working of basic functionalities of the website.

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This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information. Home Products Load Cells. You are currently searching and filtering the Home Products Load Cells product category. To search all products, please visit our Products Page. Types All types. Models All models.

Request Quote. Contact Us. Live Chat. Yemen Zambia Zimbabwe.Flintec load cells are highly accurate and built to last.

interface load cell

We pride ourselves on the quality of our products and the service we provide. Our load cell sensors are available globally. If your application requires a custom solutionour expert engineers can help. A load cell is an electro-mechanical sensor used to measure force or weight.

It has a simple yet effective design which relies upon the well-known transference between an applied force, material deformation and the flow of electricity. They are incredibly versatile devices that offer accurate and robust performance across a diverse range of applications. As technology explodes forward, many new and exciting applications are emerging that also stand to benefit from using load cells. New advances in robotics, haptics and medical prostheses, to name a few, all need effective ways to measure forces and weights.

New types of load cells are continuously being designed to meet the needs of this ever-changing market. A typical load cell consists of two parts: the main body and an attached electrical circuit. Typically, it is made from high-grade steel or aluminium, which ensures mechanical reliability, and predictable and uniform strain distribution.

The electrical circuit is housed within the load cell, tightly bonded to the main body. The circuit includes strain-gauges which are specialised parts of the circuit designed to sense the deformations of the main body. These strain-gauges consist of thin, electrically conductive wire or foil arranged in a tight zig-zag pattern. This pattern makes them sensitive to stretch and compression along their length, but insensitive across their width.

As such, they can be precisely positioned to sense forces that run along particular axes. For example, shear beam load cells have their strain gauges positioned at a degree angle to the loading axis, so as to maximise the detection of the shear strain running through the load cell.

When we use load cells, one end is usually secured to a frame or base, while the other end is free to attach the weight or weight-bearing element. When force is applied to the body of the load cell, it flexes slightly under the strain. This is similar to what happens to a fishing rod when a fisherman hooks a fish. He secures the rod with his hands while the fish applies a force on the other end through the line. The result is the fishing rod bends.

When this occurs, the deformation is very subtle. Because the strain-gauge circuit is tightly bonded to the load cell, it deforms in unison with the main body.

interface load cell

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