Questions tagged [load-cell]
A load cell is a transducer which converts force into a measurable electrical output.
201
questions
-1
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55 views
Power management design for a portable weight scale
I want to design a portable personal bluetooth weight scale with an HX711 24-bit ADC.
Right now, my first prototype is powered directly from a CR2032 battery, and if you take into account its ...
1
vote
0answers
76 views
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 ...
0
votes
2answers
99 views
Electrical noise in 18650 3.7V lithium batteries
I'm interested in knowing the electrical noise in Volts of modern 3.7V lithium batteries, specifically my model is NCB18650B, but since I don't have an oscilloscope I can't measure it. On the internet ...
0
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2answers
88 views
Question on load cell amp HX711
How do you make a load cell's amp HX711 measure both positive and negative values, or how do you set the center value for it? The main point is how to set the reference voltage (?) or something else ...
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0answers
32 views
Connector for load cell
I'm working on a scale that uses a tin-plated connector between the load cell and the PCB where the ADC is mounted. The connector is JST ZH (4pins) tin-plated.
During testing of this design, I have ...
0
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2answers
66 views
CS5530 - Read serial data through SPI [closed]
I am trying to read data from a CS5530 using SPI.
I have gone through the complete datasheet but I don't understand what is missing. I am getting the same value every time even after changing the load ...
1
vote
1answer
40 views
Wheatstone Bridge strain gauge thermal compensation design
I'm designing a full Wheatstone bridge for measuring the bending strain in a steel bar.
I have a circuit available to me that uses an ADS1232 to measure the output of the wheatstone bridge.
When ...
0
votes
2answers
81 views
Oscilloscope or bench multi-meter for ultra high sensor sample rate measurement
I need a device to measure the output of a load cell at very high sample rates. I am aiming for a sample rate of at least 100 kHz. For this goal, I wanted to ask if it would be better to use a bench ...
0
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0answers
27 views
Arduino Load Cell Limitations
I came across this forum in my research on load cells for a project at work. I had order the load cell and an amplifier/display but turns out there's no way for the display to show lbs it only shows ...
0
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1answer
79 views
Minimize load cell amplifier noise and interference INA122P
I am trying to simulate car pedals with load cells. For that I wired up 2x20kg load cells and 1x 100kg load cell each wired to a INA122P which join up at a stm32f103c8 blue pill board.
The circuit ...
0
votes
1answer
108 views
Calibrating 500 kg load cell with ESP32 and HX711 without putting actual 500 kg on it! 3 V excitation
I am making a 500 kg scale using ESP32 and HX711. It is battery powered and using 3 V excitation.
In calibration process , I increase the weight by 50 kg steps and read the HX711 output and then use ...
12
votes
3answers
1k views
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/...
0
votes
1answer
64 views
HX711 powered directly from coin cell
Is it a good idea to use HX711 in a project (personal weight scale) that is powered directly from a coin cell (CR2032) without any external or its internal voltage regulator? I shut down the whole ...
0
votes
1answer
62 views
Parallel load cells on a same current source
I need to read 4 load cells with relatively low resolution (12 bit is OK) and frequency (10 SPS is sufficient). The prototype used 2 ubiquitous HX711 breakouts with each powering two load cells in ...
0
votes
2answers
54 views
Dimming energy with load cell
I'm a lawyer with no technical background. I'm just a geek! :D
I wonder if it is possible without using a micro controller can a load cell dim the amount of energy supplied by a 3V battery?
The ...
0
votes
1answer
126 views
Connecting multiple full bridge load cells together with HX711
I am doing a project where I need to connect 2 or 3 full bridge load cells (the one with 4 wires) together. I have read that to have such an arrangement I need to connect the load cells in parallel ...
0
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0answers
43 views
need help with small load cell and ADC
I am working on a project where I should be able to measure as low as 1mg load change. The acceptable error margin would be 0.1 mg. I am planning to use load cell with total capacity less than 10g ...
0
votes
2answers
35 views
Does shunt calibration of a sensor also correct for zero error?
In the datasheet for a load cell (shown below), it says that shunt calibration data is given, also they have mentioned the zero balance. Does the shunt calibration consider zero balance? Meaning, do I ...
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0answers
72 views
problem with GML692 load cell and hx711 stm32
I want to measure weight and send it to uart using a GML692 loadcell and hx711 ADC module using stm32f103ret6. I have several problems.
1-firstly, I should put pressure on side 2 in order to increase ...
3
votes
2answers
149 views
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 ...
2
votes
0answers
70 views
Does creep always occur with load cells, or is there an optimum weight capacity?
I want to make a scale which I will place under a wood stove (downdraft gasifier) to measure the amount of wood that goes into the wood stove. The amount of wood which is being measured will be ...
0
votes
2answers
33 views
TRT-25 and Arduino Uno
I need help on a project I am working on.
We are trying to integrate a reaction torque sensor and I am having a hard time deciding how to go about it.
Previously I assumed that like my load cell I ...
1
vote
2answers
158 views
Need help fault finding a custom PCB
I am designing a custom circuit board for a CG scale test instrument to find the centre of gravity for model airplanes. My design is based on the model here: https://github.com/olkal/CG_scale and it ...
2
votes
0answers
44 views
Instrument amplifier output continuing drifting
I'm using AD8226 to amplifier differential signal coming out of a load cell, the output of the AD8226 goes straight into the AD7190. My load cell is full bridge with output impedance of 350 Ohm, ...
1
vote
0answers
48 views
What check can Ι perform to verify that a load cell is operating properly?
About five years ago I was tasked to develop the software for a small custom made testing machine (everything is custom-made from frame, to the measuring system). Last year, I was volunteered to &...
0
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0answers
35 views
What are the trade-offs between different values of resistance for a wheatstone bridge?
I have a loadcell with a bridge resistance of 10k and I've asked the manufacturer for a new design with RTDs and a slight mechanical change, and as a consequence, the manufacturer's proposed new ...
8
votes
4answers
906 views
Active guard shielding for instrumentation amplifier
I want to use the the AD8221 amplifier as a conditioner for my load cell. I saw that to reduce noise I can use an "active guard shield driver" between the "REF" of my amplifier and ...
0
votes
2answers
46 views
How to change get positive value on my weighting Scale?
My weighting Scale is working fine when I keep weight after the start. But I am getting stuck when I keep weight before starting my weighing device. When I do this auto-calibrate with available weight....
6
votes
4answers
1k views
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....
3
votes
1answer
535 views
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,...
0
votes
1answer
104 views
AD7190 voltage reference
I'm using AD7190 with a 4-wire load cell to build a pressure acquisition board. From ADI reference design(CN0102), I understand that connect sense+- lines of a 6-wire load cell to the ref+- pin of ...
0
votes
0answers
143 views
MCP3561 Configuration registers resetting upon relay activation
I am looking for advice on how to solve a problem I'm encountering with my PCB project. The application involves reading a weight from a cluster of load cells and activating a relay that controls a ...
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votes
1answer
41 views
Weight sensors? Load cells?
Apologies for a novice question. I'm looking into designing a system which would detect presence of certain objects on say a shelf. I think (not sure) I need to use "load cells" for that. Is ...
2
votes
0answers
341 views
Homemade NAU7802 breakout board not preforming like reference
I am designing an NAU7802 breakout PCB for a small weight scale project I'm working on, but I've had bad luck getting it working. I am comparing its performance with the Sparkfun Quiic Scale (their ...
2
votes
0answers
41 views
Use of a three wire load cell
I am currently doing a project which requires the measurement of forces on a surface and to achieve this we are using 3 wire load cells.
The problem that I am running into is no matter how I orient ...
0
votes
0answers
56 views
HX711 and 50kg load cell - possible update speed / dynamic load
I bought this 50kg load cell and an hx711 which I want to connect to my raspberry pi zero.
I'm wondering how accurate they are if I load them with a dynamic weight.
To take a simple analogy: could I ...
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vote
0answers
140 views
HX711 noise, but only in a specific environment
I'm working on a small project at my farm to automate vegetable weighting. The system consists of an STM32 MCU, some additional ICs (matrix decoder, parallel-serial converter for some push-buttons etc....
0
votes
1answer
106 views
Suitable op-amp and voltage regulator for 16-bit ADC
I would like to use the AD4008 16-bit ADC from Analog Devices to sample a load cell. I also need a linear regulator and driver amplifier and instrumentation amplifier.
I am curious to know if these ...
0
votes
0answers
145 views
Reduce load cell creep and drift programatically
I am trying to build a weigh scale and have read through the parameters that affect its reading in the long run. My question is can we reduce the Creep and drift of the load cell by compensation ...
3
votes
1answer
433 views
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 ...
2
votes
1answer
66 views
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 ...
0
votes
2answers
104 views
Linearizing a load cell
As I understand it most load cells (all?) are only approximately linear. To improve the linearity would a 3 point calibration be sufficient? For example, at no load, half load and maximum load. If so, ...
0
votes
1answer
147 views
How to determine if a load cell is quarter-bridge, half-bridge or full-bridge?
Im looking to purchase 4 disk type load cells for weighing applications but it doesn't mention what configuration it is in (quarter bridge, half bridge etc.) Is it safe to assume 2 wire load cells = ...
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vote
2answers
2k views
Load Cell ADC HX711 Alternatives?
Looking for an HX711 ADC alternative. Sparkfun sells a pricey breakout board with the chip, but I cannot source the IC anywhere online for some reason 🤷♂️. Are there any ADCs out there that have a ...
0
votes
0answers
85 views
Load Cell Decreasing Output
I built the following weight system using a Load Cell and Hx711.
I am using an Arduino UNO and running the calibration sketch in HX711 library.
However, I noted one interesting behavior that you ...
0
votes
1answer
97 views
Regarding PLC and several input/ output modules
I have to use more than 40 servo motors and 20+ load cells using PLC. But the problem is that I have to use many I/o modules ( that is costly and hectic). Can I reduce the no of I/o modules by any ...
0
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0answers
917 views
How to connect two load cells to one HX711?
I have two 5 kg load cells and one HX711. The project's goal is to connect them together, and measure the weight of the same object. I would like to get the average in order to make my calculations ...
0
votes
2answers
682 views
How does the HX711 circuit work?
This scheme will be designed for weight scales. Why is there a transistor installed.
And I want to understand why need capacitors and resistors in this circuit. (their purpose)
The documentation does ...
0
votes
1answer
951 views
HX711 chip not working
I'm working on an electronic weight scale using MSP430 and I need your help:
I've written the code using Energia and I've used the HX711 module for testing and everything works just fine. The final ...
0
votes
1answer
152 views
Can I "sum" internal ADC channels to achieve extra bits resolution?
First of all I am a newbie in electronics.
I am building some weight scale applications using (as seen everywhere) load cells wired to a HX711 ADC and a ESP8266. I am now giving a try to the Texas ...
