Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [load-cell]

A load cell is a transducer which converts force into a measurable electrical output.

A load cell is a transducer that is used to create an electrical signal whose magnitude is directly proportional to the force being measured. The various types of load cells include hydraulic load cells, pneumatic load cells and strain gauge load cells.

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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 three wires which seem to be connected as if…
YSN
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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/MCP3428, with added benefit of smaller PCB…
Maple
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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 round load sensors mounted with adhesive between…
Diagram Alley
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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/strain gauges) from one bathroom scale (each…
user37997
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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 generate an interrupt and wake the micro…
Caylan Van Larson
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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 weight can change from -5 to +5 kg. The ideal…
vasco
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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 smaller full-scale output? The details: I wish to…
boardbite
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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. Additionally, I would like for the sensor to be…
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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 connect a load cell with three wires to the…
David Junker
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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 Voltage for Load Cell = 5V Full Scale for load…
Lagrangian
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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 another device we are building. We have a pretty good…
Ravenant211
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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. However I feel as though there could be a vast…
Tome A
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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 creep factor, like this one, which has a creep…
koike
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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 , V4 are the output signals for each load cell Why…
Islam Gamal
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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 physically mounted to create strain and give a…
6th Sense
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