Questions tagged [load-cell]
A load cell is a transducer which converts force into a measurable electrical output.
247 questions
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3-wire load cells and wheatstone bridges from a bathroom scale
I am involved with a 4H project looking to take some weight measurements with bee hives and am trying to figure out some 3-wire load sensors to do just that.
I have four 3-wire sensors (load sensors/...
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Need help understanding schematics in LT1019 datasheet
We are currently using AD7795 to get ratiometric reading of 4 load cells. It works, but the chip stocks are rather volatile. So, I am thinking on using much cheaper and easier to come by MCP3424/...
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Digital bathroom scale circuit - how it works?
I'd like to understand how the digital bathroom scales work. I was able to gather that there are four three-wire load cells connected into the Wheatstone bridge as suggested below. The load cells have ...
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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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What kind of a sensor does a arcade punch (boxing) machine have?
I am working on a project, where I have to measure the pressure exerted by a punch. I am trying to understand how an arcade machine works, and see if I could replicate the same mechanism in my project....
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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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How does a bathroom scale automatically power on when I step on it?
When I step on a bathroom scale how does the circuit turn on? I've disassembled these types of weight scales looking for obvious hardware switches, but none exist. I suspect the ADC is configured to ...
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Connect HX711 to a three wire load cell
I have the following load cells:
I'm using the following HX711 amplifier
Every guide i can find on the internet describes how to connect a load cell with four wires to the amplifier. How can i ...
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Is the Excitation Voltage of a load cell a strict specification?
When using load cells (or strain gages generically), is the Excitation Voltage spec provided as a strict minimum -- or is it just a recommendation which one can go below as long as one is OK with a ...
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How to measure weight?
Last few months I am working on personal project -- I want to measure weight of beehive during the year and then save the results. Beehives has usually from 100 to 200 kg and during one day, the ...
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Does this loadcell's creep mean that I can not let a constant load on the loadcell?
I want to build a connected scale that I can set coffee powder (for example) on it and check over the internet how much of coffee I still have without going to see it.
Usually all loadcells have a ...
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Load Cell Amplifier AD620
I know AD620 is an old part but it is available at my place. I intend to develop a Load Cell amplifier. Load cell is 2mV/V. I am planing to use AD620 for it. Following are my calculations:
Excitation ...
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How to mount a Half Bridge Load cell
I have half bridge load cells similar to the ones in the image below. While I understand the circuitry and hooking up the differential output of the load cell to an INA, I am not sure how these are ...
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Arduino Leonardo + 3 wire Load Cells + INA125P – Analog Signal Bounce / Noise
I actually have a software background so my experience in electrical engineering is somewhat lacking. Never the less, I have given my first Arduino project a go and for the most part I am quite happy. ...
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Difficulties reverse engineering a digital bathroom scale
I apologize if this has been discussed elsewhere and for the length of the post. This is a group project and we plan to take the weight value from the scale and send it via a WiFi connection to ...
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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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Load cells in series
I am working with building a digital scale (of sorts) and have a single load cell working connected to my microcontroller.
If I wish to use multiple load cells, can I simply connect their signal ...
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Connecting 4 load cells in parallel
I have 4 strain gauge load cell to calaculate actual weight.I want to use summing method for 4 output signals. I searched at internet for summing box schematic I found this pic
Now if V1 , V2 , V3 , ...
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Load cell and amplifier
I'm trying to get a reading from a Digi-Star load cell.
I'm using the INA122 instrumentation amplifier, the schematic is attached.
Nothing complicated, I connect the cell output directly to the ...
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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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Detecting foot steps
I'm building an interactive disco dance floor. Like the light up dance floors from the 70's, but each floor panel should be able to detect when it's being stepped on and possibly light up to show this....
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Combination of four half-bridge load cells
I have a kitchen weight scale containing four half-bridge load cells, each cell associated to one foot of the scale.
I want to hack it to use it as a pressure sensor and link it to an Arduino ...
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Power Electronics for 3.3v or lower MSP430 + 10v sensor
After asking around I realized that switching regulators should be used to regulate the power going to the MSP430. I'm wondering (I'm not very informed in the topic of power electronics) how can I ...
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Do ADS12XX circuit need an amplifier?
I'm working on a project that use various analog sensors (load cells, microphone, pressure, etc.) All of them have an analog standard output (mv/V). I'm using a Raspberry Pi. I want to choose a module ...
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HX711 with RaspberryPi and python
I have been working to create a digital scale for IOT project, using HX711 ADC.
The problem
Since it is crucial to have wifi connection, I use Raspberry Pi, to control the scale.
Everything works well,...
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What is the pressure/force sensor used in the Beddit?
The Beddit sleep-tracking device (Beddit and @indiegogo) has a pressure sensor that looks like a thin (~0.3mm?), flexible tape about 2ft long. The tape seems to be constructed of several layers ...
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What does %FS (Full Scale) represent in load cell?
Lets say that a load cell has these specifications:
Rated Load = 500 g
Rated output = 1 mV/V
Excitation voltage = 12 V
Creep = 0.02 %FS / min
Then the output range should be 0--12 mV.
Does %FS mean ...
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Monitoring a large array of load cells
I have a large array of 8x8 load cells I'd like to monitor, and I'm looking for an efficient way to do that.
Obviously, one option is 64 independent instrumentation amplifiers, but that's expensive ...
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Cheap load cell and ADS1232 strange oscillation
I'm using four of these load cells wired in parallel and connected to an ADS1232. Overall the device (scale) is working well, but I am seeing a strange signal over a period of a few minutes after I ...
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Build a scale without computer
I need to build a scale that is not attached to any computer. The goal is to weigh a dustbin and show the weight value on a small LCD screen. The weight I want to measure is approximately 10 kg, but I ...
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Remove spikes from Load Cell readings
I have developed load indicator interfaced with load cell to display the value of load. The device is to be used in on-line weighing of a bag that is moving over the conveyor. Due to the mechanical ...
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AD620 in-amp reference pin
I have a weighing scale project using a 200kg load cell with a rated output of 1mV/V. I used 5V as excitation voltage and an Ad620 in-amp for my amplifier. I only need atleast the 0-100kg so I only ...
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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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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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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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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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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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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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Why there is a resistor soldered across output (green) and excitation (black) in a S-Beam load cell?
As the photo displayed above, it is a S-Beam load cell. We selected the same color of wires that connect the header of the load cell. As we can see, there is a resistor soldered across output (green) ...
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Configuration of load cell on digital scaling
UPDATED!
Anyone can tell me how to configure the load cell (like mine is MLC902) on digital scale? How is the calculation voltage output when is loaded by 50kg or 100kg?
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Problem of noise with load cell and INA125P + Arduino Uno
I am here with a problem that I cannot solve. Here are the facts:
I have a load cell : http://www.robotshop.com/en/micro-load-cell-50-kg.html
that I want to use in both directions, from -30kg to 30kg ...
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What sampling frequency do I need for a non-periodic signal?
I have a load cell attached to a crimping press (20mV Full-scale differential voltage). The press presses down on the load cell when it's crimping a terminal and the load cell outputs a differential ...
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Why aluminium for load cells?
I am currently working with load cells for weighing small masses. Almost all of them, as far as I have looked, have been made from aluminium. Given that repeatability is critical, why aluminium and ...
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Three-wire load cell and HX711 weight compensation
In my project I use a 3-wire load cell (like this (3-wire 50kg), but mine were purchased from eBay) and an HX711 for weighing.
My wiring is like this (but I use an Arduino Mini Pro 3.3 V):
Apparently ...
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How to connect a load combinator to a load amplifier for load cells
I would like to link 4 load cells sensors to an arduino. I am trying to follow this tutorial. I am using this load combinator
and I need to connect it to this load amplifier
The combinator has E+ E- ...
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Arduino with Weighing Scale
Let me preface this by saying I'm a total beginner to this. My area is Software, not usually electronics; and I haven't done any since I was in high school.
I've done a lot of reading about ...
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Understanding load cell and instrumentation amplifier
I want to build a weight scale with 0.1 gram resolution. But I have some problems in my initial stage.
I am using a load cell with sensitivity of 1mV/V and excitation voltage of 3 V.
With no weight,...
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Hacking a four load sensor based personal weighing scale
I am trying to hack a personal weighing scale.I had taken help of this tutorial but the language used in this is not very easy to understand due to the non-standard naming used for load sensor wires, ...
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Multiple ADC readings in Arduino Uno with INA125 problems
First my system used four cheap resistive load cells (maks 5 kg, input 5 VDC) to measure COG of a quadrotor. The measurement pan dimensions are 60 cm x 60 cm and made from glass (...
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Hooking up a load cell to a temperature logger
I have an idea for little project where I want to log weight changes (standalone) on a bee hive, preferably low-cost.
Now there's a lot of cheap temperature loggers on the market, for example this ...
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