Questions tagged [strain-gage]
A strain gauge measures the physical strain on an object. The most common types are a metallic foil attached to a flexible backing where the resistances changes when subjected to compression or tension.
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INA125P does not amplify correctly
I am trying to setup a Wheatstone bridge with just strain gauges (full bridge type 3). I am attaching it to a carbon fibre rod, so the strain is very tiny. When I just measure the output of the bridge ...
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How to read Kyowa strain cage specification?
These pics are from Kyowa strain cage specification which came with the strain cages.
In "thermal output" formula there are T1, T2, T3 and T4. What are those? I would understand if there ...
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Interference Issues with Arduino Mega + 2xSPI devices
I’m currently working on a project using an Arduino Mega, where I have two devices connected via SPI: a BB-ADS1220 (for reading 2 strain gauges) and an LSM6DSO (accelerometer/gyroscope). I was able to ...
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Strain gauge - wheatstone bridge: sensitivity to temperature changes
I have made a strain gauge measurement system using 3-wire quarter-bridge configuration as depicted here:
The bridge is connected to ADC (ADS1262) with ratiometric connection. R1, R2 and R3 sit on ...
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Mysterious artifacts in my strain gauge data. Can anyone suggest a possible source? [closed]
I'm working on a project where we are collecting timeseries data from multiple strain gauges. We are seeing a strange pattern of artifacts in our data.
The artifacts appear as sharp 'spikes' with a ...
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Simplest way to connect a single strain gauge to HX711
I want to make a machine end-stop trigger using a strain gauge in a location where regular end-stop simply wouldn't fit - a moving part pushing against end-of-track bar, detect the bar is under strain,...
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Bad AC response from bridge circuit
Followup to this question.
Hi. I have the following bridge circuit to simulate a strain gauge.
I am conducting an AC sweep of it as another part of my circuit (currently disconnected) that uses the ...
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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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How do I calculate the minimum deflection I can sense with a strain gauge, like the BF350-3AA?
I have a strain gauge (the BF350-3AA), and I will be connecting it to an HX711-based amplifier sensor.
From its low-quality datasheet, I've pulled out the following figures:
Nominal Resistance: 350 ...
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How to demodulate a signal that was frequency-modulated by an offset sine?
I have a strain-gauge (SG) in a Wheatstone-bridge (WB) configuration that I would like to measure on the 0-250Hz band on 16 bit ...
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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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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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Find gauge factor of a strain gauge
I have recently bought a few strain gauges (BX 120-3AA) of resistance 120 ohm. As I bought it from a local market I do not have any datasheet of it.
How do I find the gauge factor?
I guess it's ...
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Strain gauge connected to op-amp: finding its range of measurement
Given here (copied below) is a quarter strain gauge with R1 = R2 = R3 = R4 = R = 120 Ω and R4 = R + ΔR as the variable resistance, where the change ΔR is caused due to mechanical forces applied to ...
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Are the assumptions for a Wheatstone bridge still valid while connected to a differential op-amp?
While analyzing the Wheatstone bridge independently, the same current is considered to pass through both resistors in each branch of the bridge (i1=i3 & i2=i4.)
I've seen the same assumption was ...
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Vibration and noise pickup from a "quiet" machine base
I am trying to do a noise/vibration profile on a piece of machinery in an incubator. Ideally, it should not be subject to vibration, but inevitably there will be some.
In addition to the internal ...
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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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Strange behaviour of a Wheatstone bridge
I am trying to do some strain measurements. I am using a strain gauge in a Wheatstone bridge configuration. The connection is shown in the image below:
simulate this circuit – Schematic created ...
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Instrumentation opamp saturating
I'm building a circuit to measure signal out of a wheatstone bridge for strain gauge.
here is the schematic:
simulate this circuit – Schematic created using CircuitLab
I applied +-1.5V with ...
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Which amplifier module to use for strain gauge/thermocouple voltage measurements through multimeter? [closed]
I wish to measure the voltage difference across the ends of my load cell and thermocouple using a multimeter, but my multimeter cannot accurately read such small voltages. The range of voltages to be ...
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AD620 input voltage range identification
I wish to buy this AD620 amplifier module for amplifying my strain gauge voltage. I also wish to use it with my thermocouple. Basically, I want to accurately read DC voltage values from around 0.1 mV ...
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LM358 input voltage range identification
I wish to buy this LM358 amplifier module for amplifying my strain gauge voltage. I also wish to use it with my thermocouple. Basically, I want to accurately read voltage values from around 0.1 mV to ...
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Instrumentation amp giving only positive output (with + and - power supplies)
I'm using an instrumentation amp for a bridge circuit for strain gauges. However, the output range is always positive (the lowest value I can get is zero).
The amp I use is AD620. For power supply I ...
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What is this logo? ☰M☰M☰ / ☰W☰W☰
Seen on a strain gauge, and looks familiar, but I can't identify the manufacturer. Who makes strain gauges with a logo consisting of:
Two letter Ms (or maybe W if it is upside down)
Three horizontal ...
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How to make sensor input look like high impedance on loss of 5V power?
I have a strain gauge sensor with a full-scale output of about 8mV and an output impedance of 5K ohms. We will be measuring its value with a max sample rate of 500Hz, and 10 bits of resolution. It ...
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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 ...
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Wheatstone bridge BF350 strain gauge to Arduino GPIO HIGH (fast)
Looking to use a strain gauge as a trigger (Z-stop on 3D printer). I also have some other applications for this circuit. Essentially, I want the output from the op amp (TL072 - because of high slew ...
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How do I reduce strain gage drift?
my name is Joe Vaccarella. I am a research assistant at the University of Rochester.
I’m currently conducting a project where I have 4 strain gages, mounted on a polycarbonate tube. (one gage on each ...
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How to stop a high torque stepper motor when a certain amount of load is applied?
I’m looking for some design suggestions for stopping the linear actuation of a platform when too much load is applied to the moving plate, for both normal and axial loads. I mainly do not want to ...
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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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Strain gauges' readings at 1 kHz
I want to connect 8 strain gauges to an aluminum scooter frame and capture readings at 1 kHz. The strain gauges are Full bridge 350 ohms with a very small output voltage (in the range of mV). I have ...
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What is the use of this component packaged with a strain gauge?
I ordered the strain gauge with code 865-6235 from rscomponents.
I don't understand the use of the other highlighted part. Can someone help me?
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Problem with op amp output hitting bottom rail on output stage for DIY 3D printed strain gauge. High gain is needed
So the goal is to take our differential input from our experimental full bridge strain gauge and amplify the signal to a gain of roughly 5500. The output signal would then be going into a 12-bit ADC ...
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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 ...
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Strain gauge installation tester vs. insulation tester
An insulation tester (or a Megaohmtester) costs in the range of 500-1k USD and can measure up to G-Ohm and more in resistance. Even a big brand tester like Fluke 1587 costs under 1k. Not saying they ...
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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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Why increasing bridge ratio improve efficiency?
From The Bonded Electrical Resistance Strain Gage by Murray & Miller where it says:
For operation with a single gage, and under some conditions with two
gauges, the efficiency can be improved by ...
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Common voltage of 2 op amps instrumentation amplifier
I am trying to build an amplifier for a strain gauge sensor using the 2 op amps instrumentation amplifier design provided in the Texas Instruments note: https://www.ti.com/lit/an/sboa247/sboa247.pdf?...
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Strain gauge measurements with carrier frequency
In near future, I would need to do strain gauge measurements using HBMs instruments, the amplifier will be MX1615B.
In my case, the gauges will be placed near a 50Hz gearmotor and run with VFD.
As far ...
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Strain gauge in a voltage divider
I have a strain gauge mounted in a voltage divider as in the image below:
simulate this circuit – Schematic created using CircuitLab
where \$R_{g}\$ is the resistance of the strain gauge when ...
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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 ...
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Why are two pairs of a wheatstone bridge of opposite direction?
I wonder why are, e.g. when using a wheatstone bridge in combination with strain gauges, two of these SGs do have a positive k-factor and the other two a negative k-factor.
Gladly, there is already ...
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4-Wire Strain Gauge Measurement
I want to accurately measure the resistance of a single strain gauge, unaffected by lead wire resistance and with ratiometric ADC conversion to compensate for excitation drifts.
I know for RTD ...
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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 ...
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Load cell behaving weirdly. Output magnitude of force depends on which side is held and which side force is applied
also asked at: https://forum.arduino.cc/index.php?topic=670246.0
I have a generic load cell (image) and am using Hx711 which is connected to arduino. The code is from Instructables.
When I fix and ...
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Loadcell strain gauge with 10 V excitation
I am designing loadcell (spec) measuring using 24-bit adc (MCP3561) with excitation 10 V. But I couldn't find the reference design for 6-wire loadcell that its sense pins connect to ref+ pin of ADC. ...
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Obtaining Accurate Measurements from Strain Gauge
Background I have a strain gauge that I need to obtain measurements from. The product page indicates that the sensor is a half bridge configuration (one active/one compensating element). The sensor ...
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Options for impact sensors?
I'm looking for a sensor to sense impact, let's say the sensor is placed behind a thick metal/wood casing, the impact depending on the amount of force could either deform the casing or only causes ...
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Should we use wheatstone bridges nowadays?
For measuring strain gauges, the Wheatstone bridge is the historical choice.
In a quarter Wheatstone brigde (\$350 \Omega \$ typically (?)), with a high input impedance amplifier, and some bridge ...
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Operational Amplifier and Strain Gauge
My laboratory involves using a strain gauge and an instrumentation
amplifier to amplify the signal from the strain gauge. The op amp schematic is shown below:
Any assistance with the following ...
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