Questions tagged [load-cell]
A load cell is a transducer which converts force into a measurable electrical output.
247 questions
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Why do my HX711 load cell readings drift significantly over time?
I bought four 5 kg load cells (link) and connected them all together (all white cables, all green cables, etc.). Then I hooked them up to the HX711:
When I read the values from the Arduino using the ...
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Instrumentation Amplifier and differential ADC Arduino Mega
I am working on an acquisition system, which measures tension and compression in a load cell. I amplify the signal with the Instrumentation Amplifier INA128P, and after that I connect it to the ...
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Precise Electronic Measurements
I've been looking into various electronic components and noticed rampant 5%, 10%, and even 20% tolerances and accuracies not only in basic components such as capacitors, inductors, and resistors, but ...
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FX29 Load Cell - Sleep Mode vs Update Mode
Context
I'm using an I2C based Load Cell the FX29.
I have been having troubles where the I2C sensor does not give me any data unless I manually unplug and replug the sensor while the Arduino sample ...
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Trying to set up a data acquisition system--have some questions
I'm setting up a data acquisition system for some load cell, pressure ducer, and thermocouple inputs. Currently looking at the LabJack T7 for my ADC and INA125 for my load cell amp. PTs are self-...
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Load cell mathematical model
I'm studying a solution for a weight measuring system that's affected by enviroment vibration - a load cell fixed on a "shaky" frame. My first thought was to use a 3-axis accelerometer (or ...
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Load cell value becomes negative when above certain force
I have a 100 gram load cell with the hx711 amplifier board. I have it wired up to an arduino nano with an NRF24L01 module to send the raw value to another arduino nano.
The problem is that when I aply ...
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hx711 high current consumption
I have one hx711 module connected a 200 kg load cell and I'm measuring a high current consumption: around 13mA where the datasheet says it should be around 1mA.
Cabling is as follows: usb to the mcu (...
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Differential vs. Single-Ended amplification for sensor sampling
I'm designing a load cell amplifier that should be low-cost, and functional in a noisy environment. The load cell is a 1k balanced full-bridge on a single package. The read speed requirement is only ...
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10 µF and 0.1 µF capacitors not making any difference in filtering out noise
I have two circuits (green and brown) featuring a load cell, HX711, and ESP32-C3:
The HX711 and ESP32-C3 go on top of those round female pin header.
The only difference between them is that one is ...
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I2C communication between load cell and Arduino
I am using Load Cell (FX29 Data Sheet) and Arduino for measuring force. Every time I disconnect and reconnect Arduino from USB I get one of the following readings on serial monitor:
Correct expected ...
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INA125 Reference Voltage lower than expected
I am using a INA125 to amplify the signal from a load cell. When I connect everything according to the datasheet as seen below, the reference voltage drops when I connect the load cell. I am supplying ...
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Extending load cell wires for weight transmitter connection
I have a load cell that I want to install in a certain location. I plan to connect its output to a load cell transmitter, which is approximately a meter away from the maximum length of the load cell ...
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Is it normal for load cells (and HX711) to give negative values when there is no load applied?
My load cell (and HX711) gives values like these (44~45 g is with an object put on top):
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Is it possible to see which load cell is accounting for how much of the total weight?
I'm a newb when it comes to electronics, learning it as a hobby and was wondering if it was possible to determine which load cell accounts for what % of weight when connected in wheatstone pattern. I'...
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Load cell simulator-mV/volt generation
I am trying to simulate a full bridge sensor load cell.
Here is the reff to the image: https://www.scribd.com/doc/140674267/Load-Cell-Simulator-v2
Above is the reff circuit I am using. I know that ...
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Tension load cell options
I'm designing something similar to an electronic hanging scale (think a heavy object on the bottom, with a scale attached immediately above it). I am not that familiar with what the most typical way ...
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Is there a switch that turns on when it detects a "pull" of a few grams on a string?
I'm working on my first Raspberry Pi project. I'd like to turn my project "on" when a force, of a few grams, is applied to a string (i.e. "pull the string" to turn the unit on, the ...
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Matching ADC and encoder data in time
I'm trying to measure load and elongation in homebrew testing machine. The load is measured by the AD7791 ADC and elongation is measured by linear incremental encoder (quadrature encoder + MCU ...
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ADC count not stable when tapping into a commercial weight scale SPI
I am in the process of designing a weight scale.
To test whether I could achieve the same results in the software I decided to disconnect the MISO, MOSI, SCK and CS from a commercial weight scale MCU ...
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Methods for improving/smoothing the load cell signal
I am using a Delta AS02LC-A cell module and a Zemic 25 kg load cell. Here are some details of the load cell calibration certificate:
And this is the appearance, specifications and wiring diagram of ...
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Why does bathroom scales use half bridge load cell rather than 4 full bridge loadcell in parallel? Except for the price, is there any other reasons?
I have been wondering why does bathroom scale uses 4 half bridge loadcell connected like this figure bellow rather than using 4 full bridge loadcell connected in parallel? Except for cheaper ...
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Load cell trouble, part 2. I have huge, rapid drift, and variation
I've posted very recently about my trouble with load cells. Baffled at how poor my results are. Huge drift to the point that I wouldn't even call it drift. Very noisy readings, too, but I don't know ...
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All load cells and ADCs I've tried give horrible readings. Don't understand how anyone makes anything with them. Losing my mind
I've been fighting with load cells for something like two weeks now. Lost two USB ports on my laptop to 12V in the process. Yet to hear of anyone having this much trouble. Looking for help.
Here are ~...
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load cell calibration with HX711
I am trying to calibrate four 50kg Weight Sensors with Arduino's HX711 Amplifier AD Module. I am getting a variable range of errors. I am using this video as a reference link below. It shows me use a ...
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How to use a load cell?
This is the first time I'm handling a professional load cell, and nobody else at my company has worked with them before.
I'm quite sure I've broken the load cell. I just checked the datasheet and see ...
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Making an automated rig for chemistry test. Cannot read a load cell accurately. Constant drift
I'm making this rig to measure rates of carbonation. It's sensing 6 different variables including mass of sample. The board is Wi-Fi capable (ESP32 WROOM), so I can publish results wirelessly and see ...
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Why is does my INA121 instrumentation amplifier not amplify my load cell's signal at high loads?
I am applying a high load (150-200lbf) to a (mV Wheatstone bridge) load cell rated for 200lbf (link to datasheets at bottom), and amplifying the differential signal with the INA121 instrumentation ...
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DG408 Multiplexer Issue
I connected a DG408 8:1 Multiplexer to 6 Futek Load Cells; the signal of each load cell was amplified by an "ICA-1H" strain gauge amplifier. The output signal of the multiplexer was ...
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How do I read a load cell just with this data?
I have a load cell (capability = 23 kg or 50 lb.) Its output is 2 mV/V. I have read that that means 2 mV per each excitation volt.
The power connection of this load cell is +15V-GND, so 0.002 * 15 = ...
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Inaccurate measurement double load cell circuit
I’m building a circuit with two load cells and I have some issues getting accurate measurements. At first I just soldered the load cells onto the load cell amplifier but as the connections seemed bad ...
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Using an ESP32 with a load cell with 5 V recommended excitation voltage
I am making an IoT device using an ESP32 that powers a load cell with 5 V recommended excitation voltage. I know the ESP32 output is 3.3 V, but I need it to be 5 V. Is there a way to do this with a ...
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Load Cell Bridge Resistances are ok but I cannot get reading from load cell
I have planar beam load cells that are not functioning. I bought a digitizer which was giving me a reading error which alerted me to an issue. So I unplug the cells from the summation box and I am ...
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Creating a Strain Gauge Load Cell
I want to make my own load cell; how specific do the materials need to be?
For example, is it necessary to buy all the cleaning and gluing equipment shown in strain gauge installation videos? Or can I ...
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What components are used for pressure sensing in a DanceRush Stardom dance pad?
This is an arcade rhythm game called DanceRush Stardom, a similar concept to Dance Dance Revolution, but the dance pad acts more like a large screen and tracks both feet.
Here is an example video of ...
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ADC CS5532: "digital gain scaling" - ADC Calibration without full scale signal
I'm making a digital weight scale with Arduino and CS5532.
My problem is to calibrate adc with the offset signal and a known weight signal that is not full scale point.
The CS5532 allows me to ...
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Why does HX711 load cell amp not have an I2C address?
Context: I am trying hook up the TI CC26X2R1 dev board to a 5 wire load cell to act as an end device in a Thread network. I use the Sparkfun HX711 load cell amp to amp and as an ADC (links for both ...
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What is the maximum frequency that I can get reliable weight data from a strain gauge load cell?
I need to build a scale that uses a strain gauge load cell such as the one below:
https://cdn.sparkfun.com/datasheets/Sensors/ForceFlex/TAL220M4M5Update.pdf
The weight data will need to be stored with ...
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Coin cell holder not powering circuit
I use a 3023 Keystone electronics, through-hole coin cell holder in my circuit. When I connect the Arduino to my computer, it gets powered up without any issue and my circuit works just fine.
The ...
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Thermoelectric EMF problem for low voltage measurement load cell
The resolution of a load cell is highly dependent on its capacity. That's because the higher the resolution and the higher the capacity, the smaller the voltage change. For example, many companies ...
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Comparing ADC noise parameters
I'm looking at two ADC parts the ADS1230 and the ADS1231; the 1231 is an almost pin-compatible upgrade (if you don't need the ×64 gain setting) which provides 24-bit resolution and some more noise ...
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What is the ideal method of sensing whether 4 points on the bottom of a device are all depressed to indicate contact?
I am trying to place a sensor or switch on each corner of some desktop PCs so that if they are lifted an event is triggered like locking the computer or encrypting it.
So far I have considered small ...
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How to improve HX711 to feed two or more load cells in parallel?
HX711 datasheet
Load cells I'm using
I have typical load cells and want to connect them in parallel directly to the HX711 "A" section of the amplifier.
The load cells have an input ...
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How can I calculate the values of the four resistors in a Wheatstone bridge?
I measured black-red = 400ohm, green-white = 350ohm in a 5kg loadcell.
How can I calculate the resistor values?
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How to read four load cells with a single ADC input?
I am currently using strain gauge based load cells and want to weigh 1-5kg granular products on whatever container with 4loadcells beneath. I encountered a problem with connecting load cells in a ...
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Question regarding the ADC MCP3201 interfacing with PIC16F72 microcontroller
I provide the 1.2 MHz clock to SCK pin to the ADC from PIC clock pin, but how I can receive the data from MCP3201 ADC, which provides a 12 bit binary data on SPI pin SDI of PIC? Buffer of PIC is 8 bit ...
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How do I remove bathroom scale auto shutoff feature?
I’m a software guy so please excuse any silliness in this question.
I need a scale which will not shut off on its own and continuously show changing weight values.
Although I may have no choice but to ...
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How can I synchronize load cell and sensor for sensor calibration?
I have made a glove with some cheap pressure sensors with weight ∝ 1/resistance.
DESIRED OUTPUT
I now want to create a dataset with columns "Actual Weight" and "Glove Sensor Readout&...
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HX711 load cells giving wrong readings
I have four HX711 cells in a Wheatstone configuration. I use them from home automation to measure bed presence. It worked correctly for a few weeks, but suddenly stopped working (cannot get any useful ...
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HX711 zero factor
I have three load cells (YZC-1B). These load cells' capacity is 50 kg. I guess I use Bogde's HX711 library.
In monitor, the zero factor for the first two load cells is 8,000,000, but for the last load ...
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