Questions tagged [wheatstone-bridge]
A circuit to measure an unknown resistance.
135
questions
2
votes
1answer
26 views
Confusion with Wheatstone bridge resistor terminology in datasheets
An off-shelf instrumentation amplifier manual has the following indication for Rb:
And this force-transducer gives the following resistance parameter:
I guess Rb is each single resistor value of ...
1
vote
1answer
42 views
How to make a full Wheatstone bridge with 4 tee-rosette strain gauges?
I am in the process of making a full Wheatstone bridge. I was told to use 4 tee-rosette strain gauges (with axial and radial components in one gauge) to temperature correct the signals. I am ...
0
votes
0answers
16 views
Input impedance of load cell CZL635 seems wrong
I'm working with load cell Phidget CZL635 and HX711 ADC in order to make a weight scale.
Load cell: https://www.gotronic.fr/pj-461.pdf
ADC: https://pdf1.alldatasheet.com/datasheet-pdf/view/1132222/...
-1
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0answers
42 views
Equivalent resistance of unbalanced Wheatstone bridge and generalization
I was wondering what could be the simplest method to find out the equivalent or effective resistance of an unbalanced Wheatstone bridge (first figure) and if this method can be generalized further (...
0
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1answer
68 views
How a wheatstone bridge is used in operational amplifiers? [closed]
How a wheatstone bridge is used in operational amplifiers?
0
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2answers
68 views
How do I get a stable 15V signal without a variable power supply?
I'm studying mechanical engineering (inb4 easy major), so my knowledge of EE is limited and sequestered to blind application.
I need a stable 15V supply for a wheatstone-bridge strain sensing circuit,...
1
vote
1answer
75 views
Using an op amp to balance a Wheatstone bridge by heating a sensor wire
I'm attempting to create my own hot wire liquid water content sensor, the control circuitry of which is similar to many hot wire anemometers:
simulate this circuit – Schematic created using ...
0
votes
0answers
28 views
Sensitivity of half and quarter wheatstone bridge
Could anyone help me determining the different relation for sensitivity of wheatstone half-bridge and quarter-bridge using transfer function? How differently varies the sensitivity between diverse ...
1
vote
2answers
40 views
How to handle disconnected resistive sensor?
I'm trying to connect a PT100 thermo probe to an Arduino project to measure water temperature. After some research I have found and adopted a design using a Wheatstone bridge and an instrumentation ...
2
votes
1answer
147 views
How to calculate the value of the thermistor based on the output voltage of this circuit
I recently bought a board that consists of this circuitry. It came without an instruction whatsoever, so I have to figure out how to measure the temperature based on the output voltage at the To.
The ...
0
votes
1answer
33 views
Signal lines from transducer made common by op-amp
I am trying to amplify the difference between signal lines off of a Wheatstone bridge based force transducer. I've wired up an LM358N Op-Amp as shown below in a differential amplifier.
With R1=R2=...
0
votes
4answers
101 views
How does one determine the millivolt reading across a Wheatstone bridge?
When determining the millivolt reading I'm confused on the order in which you subtract V(2-4) and V(1-3).
Would it be: V(1-3) - V(2-4) or
V(2-4) - V(1-3)
I've seen it done both ways, so ...
0
votes
1answer
44 views
How to obtain a high precision mV signal within a specific interval using a variable resistor?
I want to design a circuit which outputs a signal ranging from 0-70 mV using a variable resistor ranging from 80.51 Ohm - 183.05 Ohm and a supply voltage of 12 V. My idea so far has been to make a ...
0
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0answers
38 views
INA125 problems
I'm trying to measure a bridge sensor using an INA125 connected to my Arduino and Adafruit ads1115, but the output seems stuck on 5.88V (the power supply is 12V singl supply). Its connected as in the ...
9
votes
2answers
1k views
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 ...
3
votes
3answers
266 views
Reasons for strain gauge drift
I'm testing a load cell where the result drifts over time.
By weighing it down with a known weight over night, the result crept up by 10% in 18 hours. It's a completely linear increase, with ...
2
votes
2answers
330 views
How does full wheatstone bridge with strain gauges work?
I have gone through a number of tutorials on Wheatstone bridge and how to use it to sense load using strain gauges. I have also gone through the calculations where one of the resistors of the ...
1
vote
1answer
131 views
Why is my amplified strain gauge output so unstable?
I've attached a strain gauge to a bending arm of a robot, and it varies by about 1.5 ohms from 356 to 357.5 ohms. I place this in a Wheatstone bridge.
The strain gauge is R3. R1, R2, and R4 are all ...
0
votes
1answer
169 views
Wheatstone bridge and difference op-amp
I use Wheatstone bridge as a dual voltage divider to feed both inverting and non-inverting inputs of differential op-amp:
Theoretically voltage can be calculated using voltage divider expression: Va =...
1
vote
2answers
79 views
Low current strain gauge
I am trying to make a low power device (based of RSL10 bluetooth SoC) that would sample a strain gauge @1kHz and transmit the measurements. The current drawn by the running SoC is about 1.5mA, while ...
2
votes
3answers
108 views
Mathematical help with Wheatstone bridge
This is a homework, so I won't ask for a complete solution, but can anyone tell me how should I approach this?
I've been sitting now for hours without any progress, all that I know is the answer ...
0
votes
1answer
68 views
Output Voltage Formula verification of Operational Amplifier circuit
I'm trying to built an op-amp circuit for a PT100 temperature sensor.
I've found the following circuit diagram online (from a polish website):
And I'm trying to find the formula for the output ...
0
votes
1answer
73 views
Difference between Proteus results and KCL-deduced formula
I'm designing a small circuit using an op-amp for a temperature sensor (PT100).
I took the design online (see below).
I tried to find out the formula for finding the value Vout as a function of the ...
0
votes
1answer
215 views
Strain gauge amplifier - so much noise!
I'd like to use atmega328p to read force with strain gauge. I'm using one 1k strain gauge and 3x 1k ohms dummy resistors.
My circuit looks like that:
I'm using DAC to remove offset from bridge.
As ...
0
votes
1answer
75 views
Remove bridge offset before ICF amplifier or at FB pin?
I'm making project where I would like to read from stain gauge sensor. It will use only one 1k ohm (or 350 ohm) strain gauge and 3 dummy resistors to complete bridge (1k or 348 ohm). I'd lik to feed ...
0
votes
2answers
75 views
Wheatstone Bridge Single-Element Varying
So, this book is saying that when V_B is 10V, R is 100ohms, and delta R is 0.1 ohms, The linearity error is 2.5mV - 2.49875mV = 0.00125mV.
I don't quite understand where 2.5mV came from.
If I use ...
0
votes
1answer
93 views
ADS1115 differential output
I have the output of a wheatstone bridge going into an ADS1115.
I am exciting the bridge with a 24VDC supply and the ADS1115 with 3.3VDC through a Raspberry Pi.
The issue I am having is that when I ...
0
votes
1answer
268 views
Wheatstone Bridge - strain gauge sensor
I'm trying to optimize a Wheatstone bridge with a strain gauge sensor and I'm considering all possible wire resistances. The circuit is shown in the following figure:
I don't understand the comment ...
2
votes
2answers
112 views
How are the terminal voltages regulated for this Wheatstone bridge?
At page 34 from this datasheet the following circuit shows a single-ended amplifier used to produce single-ended gain:
As you see the excitation voltage terminals is sensed by Kelvin connection ...
1
vote
1answer
76 views
DIY water tank gauge using analogue ammeter - linearity
A follow up question to my previous on building a DIY water gauge DIY water tank gauge using analogue ammeter.
I have scrabbled together a "Euro type" sender (10 Ω empty - 180 Ω full) and ...
4
votes
3answers
663 views
What is the value of the current (i) and what is the right way to do it? [duplicate]
What exactly went wrong with the below method?
Here, in the same circuit I am getting a different value for the current in the mid wire only by rearranging the circuit.
I was trying to solve this ...
0
votes
1answer
164 views
What's wrong with this Wheatstone bridge?
I was trying to solve this unbalanced Wheatstone bridge and found that the current $i$ in the mid wire is 9A .This result was achieved by using node voltage method.
Then I rearranged the same circuit ...
1
vote
3answers
101 views
What can be the reason for the extra connections from this Wheatstone bridge to the amplifier?
This industrial amplifier is used for force transducers and here is the wiring diagram for the 6 wire transducers:
¨
And below is the terminals for the amplifier:
It seems 1 and 4 terminals are the ...
1
vote
0answers
98 views
Wheatstone gauge factor calculation?WII load cell
Currently working with the WIIFIT or WIbalance load cell. For some reason everybody wants to work with these load cell. However, there are no actual datasheet of the load cell used in the device. ...
1
vote
1answer
45 views
Is this voltage rating relative to ground or differential?
A transducer has this datasheet.
What is meant by Bu,g?
The amplifier I use applies +10V and -10V to excitation terminals so the difference between the terminals will be 20V and the excitation ...
0
votes
3answers
405 views
What does this resistor do in this RTD wheatstone bridge?
The question is in bold at the bottom, the following is background.
I am going to measure air flow with a hot wire anemometer using the FS7 sensor from Innovative Sensor Technology (IST). They ...
0
votes
1answer
2k views
How does temperature compensation work for strain gauge in wheatstone bridge
Wheatstone bridge is used for temperature compensation for strain gauges
If 2 strain gauges are connected like this figure. Due to temperature variation; the resistance Rg will change in the same way....
1
vote
4answers
3k views
How does 3-wire RTD or resistance measurement works in bridge of wheatstone?
I cannot understand how 3-wire measurement will improve the resistance measurement.
They say that IF lead resistance \$ R_L \$ is the same, it will compensate. How can this happen?
If bridge is ...
0
votes
1answer
1k views
Thevenin resistance for bridge circuit
So I've been at this question for a few hours now and i can't seem to get the final answer for a). I know how to find the the resistance of a basic Wheatstone bridge, but i don't know how to find the ...
0
votes
0answers
472 views
How to connect bathroom scale (arduino+hx711+spark load connector)
Im a new user in the electronic world. I tried to hack my bathroom weight scale but no success. There is a great tutorial which I followed:
https://www.youtube.com/watch?v=iywsJB-T-mU
my parts:
...
0
votes
1answer
288 views
Basic question on temperature compensation of resistive bridge circuits
Many force transducers like this one are made up of Wheatstone bridges and they have sensitivity which relates the force/stimulus change to the voltage change. This small voltage change then is ...
0
votes
1answer
69 views
why the 3 stage differential opamp not worked [closed]
i did the following in simulation its work.
but in practically, i cannot able to get a amplified output.
i use ic741 as a op-amp 5v input for opamp and bridge power supply... i get always 1.77v in my ...
0
votes
2answers
1k views
Strange Behaviour Using LM358 Op-Amp as Wheatstone Bridge Difference Ampliflier
I've been working on building a circuit which uses a wheatstone bridge to find the value of a resistance temperature sensor (Danfoss AKS 21) and then passes that to a differential amplifier the output ...
0
votes
1answer
119 views
How to explain why equivalent resistance between two points in this network is dependent on specific resistance?
The original network is an square network with two diagonals as you can see here there is no intersection between the diagonals.:
The question is what is the equivalent resistance between points A ...
0
votes
1answer
541 views
A way to 'digitalize' a wheatstone bridge
I am currently using a Wheatstone bridge to determine the resistance of a NTC thermistor and feed the difference to the setpoint (analog potentiometer) as the error signal to a PID controller, giving ...
0
votes
1answer
324 views
Wheatstone Bridge imbalance voltage calculation
So I have this simple force measure circuit which consists of a strain gauge SG1 and the amplifier with the Wheatstone bridge, the variable resistor RV1 is set to 200Ohms. If the strain gauge is ...
2
votes
1answer
397 views
Compensating for offset voltage in bridge measurement before instrumentation amplifier
I'm using an instrumentation amplifier (INA118) to measure the signal from a full bridge strain gauge (tension only, all 4 resistive elements are strain gauges, slow changing (DC) signal). I'm using a ...
1
vote
1answer
74 views
What type of sensor has diamond pinout like shown? Resistive bridge? Wheatstone?
I have worked with basic resistive sensors before, but I have never seen a pinout like this one and I'm not sure how the voltages work for these pins. I was told it may be a resistive bridge, but it ...
1
vote
2answers
302 views
Differential equation from a Wheatstone bridge with Inductor
I've been given the following circuit and been asked to give the differential equation showing the relationship between \$u_e(t)\$ and \$u_a(t)\$
The differential equation should be in the form
$$\...
0
votes
4answers
1k views
Finding equivalent resistance of a resistor network
In the circuit below, all of the resistors are 15 Ohms. I am trying to find the equivalent resistance between A and B.
Can we argue that since RAD/RDC = RAO/ROC that AODC is a wheatstone bridge and ...
