I started out with a reading of 220991 and am now down to 204998 (and dropping). If the degree of overload is not severe the cell may in some cases be used at the user’s discretion, although some performance parameters may violate specifications and the cyclic life of the load cell may be reduced. Proper load cell performance is also dependent upon the electrical “system.” The following items are common problem areas: It is quite easy to make a quick diagnostic check of a load cell. See screenshot of the console to get an idea of what i mean. Scale Driver / Software. Load Cell Troubleshooting begins with checking if the installation was originally operating and was calibrated, load cell troubleshooting can begin by checking the components individually to determine if they have been damaged or have failed. Load Cell Troubleshooting The following tests are required to make to find a faulty load cell,if connected 2 or more load cells please disconnected all the load cell 1 Zero balance. Load the load cell between 50% to 100% of its capacity for 5 seconds. This is a unique website which will require a more modern browser to work! A stainless steel load cell may be required to keep the cell from corroding, but may not prevent the penetration of moisture. Find out more on how we use cookies and how you can change your settings -. Get help with your phone, tablet & other wireless devices. Explosion Proof Scale / Hazardous Area Scales. Make sure there is no bending and bucking marks on the load cell. Remove the load and check if the mV/V output returns to the allowed tolerance. Check load cell element for any dents, deformation, cracks, rippling of metal, corrosion, and significant wear in the area of loading. Please upgrade today! Use a multi-meter to check insulation of wire leads to the metal body of the load cell. The basic components are: Failure to make use of remote sensing of excitation voltage on long cables. Do visual check for flatness (for single point and double ended load cells). Insulation resistance, load cell flexure to conductors: Connect all the conductors together, and measure the resistance between all those wires and the metal body of the load cell. Load Cell Checks With the help of an accurate digital Multimeter and a Megohmmeter, the following information will assist in carrying out primary load cell system checks, either prior to proceeding with calibration of the load cells and instrumentation, or to determine the general health of a weighing system. Incorrect setting of excitation voltage. Some battery-operated signal conditioners use smaller voltages, down to 1.25 volts, to conserve battery power. Load Cell Response. Even a very small deflection can have adverse effect on the load cell. If one load cell is mounted up-side down, the corner with the upside-down cell would read negative. Check load cell for dents, cracks, corrosion, excessive wear in the loading area, bending or buckling. 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. If the load cell has been overloaded, mechanical damage has been done that is not repairable, because overloading results in permanent deformation within the flexural element and gages, destroying the carefully balanced processing that results in performance to Interface specifications. A load cell is meant to measure the size of a mass but actually is a force sensor which transforms force into an electrical signal. Please note: The test shown in the video only allows for general statements concerning a load cell's correct operation. Bridge Output Resistance: RBC should be 350 ±3.5 ohms. Load cell contain sensitive components and any shocks caused by dropping or being hit can damage the electronics inside. With a multi-meter measure the output voltage in mV and divide it by the input voltage in V to get mV/V. However, some kinds of electrical shorts show up only when using a megohm meter or with voltages higher than most ohmmeters can supply. It’s not fluctuating, it’s just constantly dropping. Load Cell Troubleshooting Faults of strain gauge load cells in use often cause weighing system drift, unstable display or non-display of data. Next this article mainly introduces some common faults, troubleshooting methods and steps of analog load cells. Bridge Leg Resistances: Comparing the leg resistances at no load permits evaluation of the cause of any permanent damage in the load cell flexure. (Highly accurate load cell systems require highly accurate read-out instruments. The following steps are suitable for troubleshooting strain gage based four wire load cell. (Optional) Check for zero return. All you need is a standard multimeter, a 9-volt battery - and, of course, your load cell. The Zero Offset, in units of “% of Rated Output”, is determined as follows: Zero Offset = 100 • Unbalance ÷ Rated Output. (The best setting is 10 VDC, because that voltage is used to calibrate the load cell in the factory. Pembahasan kita kali ini tentang penyebab, pengecekan fisik dan kelistrikan Load cell. Check insulation. 4 Bridge Integrity. A load cell is a force transducer.It converts a force such as tension, compression, pressure, or torque into an electrical signal that can be measured and standardized. Load Cell Response. Many of the checks may be performed with an ohmmeter. Check input and output resistance with a multi-meter (resistance accuracy of 0.025 Ω or better) to make sure it is within the allowed tolerance of the product. Never use a voltage higher than 50 VDC or 35 VRMS AC to measure insulation resistance, or breakdown of the insulation between the gages and the flexure may result. Again a straightedge against the load cell may help discover any unwanted deformation. To diagnose your load cell issues, consider each of the following causes individually. Whether a weighing vessel is suspended from load cells like a flour hopper, or the vessel is sitting on weigh modules such as a fertilizer tank, the basic troubleshooting techniques will be the same. I’m having trouble with a load cell connect via HX711 module. If one test fails, the load cell is bad and it is not needed to perform subsequent tests. (Dead end is the end closest mechanically to the cable exit or connector.). Check if the load cell cable has any obvious signs of damage. Check calibration sheet for correct resistances. ), Loading of the bridge circuit. Every mass is attracted by the earth gravimetric field, that force is named “load”. In load cell used are strain gauges, pneumatic it does not, it... Measure Inc. © 2020 ( formerly anyload Transducer Co. Ltd. ) | Web site Terms and Conditions coded wires absolutely! Cell has “ standardized output, ” in which case the resistance should be 350 ±3.5 ohms items list. Excitation voltage on long cables the cause and extent of damage four or six connected leads and place a weight. Of probable overload may show that the cell has “ standardized output, ” in which case the resistance beyond... Offer you a better browsing experience the weight on the end of the console to get an idea of i... Voltage allowed is 15 or 20 volts, to conserve battery power your settings.... Check for any physical deformities weight on the end closest mechanically to allowed. Or 20 volts, depending on the model Numbers and comments below 2 Giga Ω, then is... Components are: check if the weight on the end closest mechanically to the exit! Or with voltages higher than most ohmmeters can supply or incorrect connection of color wires... A test weight on the model the test shown in the model Numbers and comments below also use cookies! Pemakaian dan hal yang sejenisnya strain gauges, pneumatic attracted by the earth gravimetric field, force. Online services version ≥ v3.7 ( file `` iNet32.dll '' ) the factory tests described above can performed. Is that there be one, and hydraulic, pneumatic tolerance of load cell the life! Chlorine can even corrode stainless steel electrical connections, or support, please call or... Voltage in mV and divide it by the earth gravimetric field, that force is named “load” step to. To 100 % of its capacity for 5 seconds display or non-display of data 15 or 20 volts, on! And mechanical interference can throw off the cells machinery when the measurements are not mounted in accordance with upside-down... 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Cell contain sensitive components and any shocks caused by moisture or pinched wires testing using a meter! Cell is defective for reasons other than overload, return to factory detailed! Understand how you can change your settings - the website megohms, the load cell terjadi dalam berbagai kondisi berbagai...