Questions tagged [wheatstone-bridge]
A circuit to measure an unknown resistance.
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1answer
42 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 ...
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0answers
33 views
RTD wheatstone resistance question
I have a question im currently working through, its as follows
'A platinum resistance thermometer has a resistance of 100 Ω and a temperature coefficient of resistance of 4x10-3 °C-1. Given that a 10 ...
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2answers
62 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 ...
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1answer
52 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
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3answers
495 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 ...
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1answer
114 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 ...
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3answers
82 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 ...
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0answers
43 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. ...
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1answer
37 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 ...
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3answers
230 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 ...
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1answer
719 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....
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4answers
957 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 ...
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1answer
477 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 ...
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0answers
295 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:
...
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1answer
132 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 ...
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1answer
67 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 ...
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2answers
472 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 ...
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0answers
63 views
Bridge circuit balance equation
I am currently studying bridges in electrical circuits. I have stumbled upon a schematic that I cannot find its balanced equation.
What I have tried so far is combine the R3 with L1 to a Ζ3=R3+jΩL ...
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1answer
97 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 ...
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1answer
279 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 ...
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1answer
252 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
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1answer
231 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 ...
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1answer
68 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 ...
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2answers
241 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
$$\...
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4answers
663 views
Finding equivalent resistance of a resistor network
In the circuit below, all of the resistors are 15 Ohms. I am trying to find the equivalent resistance between A and B.
Can we argue that since RAD/RDC = RAO/ROC that AODC is a wheatstone bridge and ...
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2answers
3k views
How to calculate maximum gain that can be achieved by an op amp?
I am designing a differential amplifier for a Wheatstone bridge which have small voltage variations like 0uV to 20uV. so need to design an instrumentation amplifier. I do not know how to find the ...
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1answer
2k views
LM324 op-amp wheatstone bridge amplifier formula
I'm planning to use an LM324 opamp as a signal amplifier for a cell load (strain gauge in a Wheatstone bridge). This particular application is shown in the datasheet (see image). It shows the ...
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1answer
208 views
AD8422 LTSpice simulation
I am trying to simulate a wheastone bridge amplified with an AD8422. In principle, with a Rg of 500 ohm, it should give me a gain of 40, according to $$ G = 1 + 19.8k\Omega/R_G $$ but instead I get a ...
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3answers
643 views
How do I use this Strain Gauge? (4 wire)
The load cells here: http://www.cnloadcell.com/mlc700-postal-scale-load-cell and here: http://www.cnloadcell.com/mlc714n-personal-scale-weight-sensor have 4 wires (red, white, black, green).
The ...
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2answers
1k views
how to connect strain gauge to HX711 module
I need get strain gauge reading to Arduino. so far i have found load cell Wheatstone configuration circuit here 3rd answer. I need to know if i connect a strain gauge to one +Active resistance, and ...
4
votes
1answer
362 views
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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2answers
544 views
Alternative Wheatstone bridge for thermistor - Interpretation needed
I have a problem understanding the following Wheatstone bridge circuit. It originates from a temperature controller, the voltage V_out is supplied to a PID regulator and hence can be seen as an error ...
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1answer
1k views
Why can't a Wheatstone bridge measure resistance of very high value?
The answer is from google but I don't get it. Can someone explain in more simple way?
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1answer
306 views
Backwards proof for balanced Wheatstone bridge
simulate this circuit – Schematic created using CircuitLab
We know that in this Wheatstone bridge if,
\$\bf{I_3 = 0}\$, it can be derived that \$\bf{\frac{R_1}{R_5}=\frac{R_2}{R_4}}\$ . But ...
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3answers
1k views
Strategy to balance a Wheatstone bridge for strain measurement
The purpose of my project is to build a sufficiently accurate "Strain indicator" based on the use of a Wheatstone bridge using an Arduino. Currently I am using a HX711 as load cell amplifier which is ...
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2answers
494 views
Help needed on wheatstone bridge problem
My circuits 1 professor gave us some practice problems for an upcoming exam, and I'm not sure that I know how to do this one.
My approach was to apply the circuit divider formula for the left and ...
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0answers
256 views
Output voltage approximation in Wheatstone bridge
When I calculate the potential difference in the above circuit, I find:
v1 = Ug*(ΔR+R)/(2R+ΔR)
v2 = Ug*(R)/(2R+ΔR)
Uo = ΔU = v1-v2
ΔU = Ug*[ΔR/(2R+ΔR)]
But it is always approximated to:
ΔU = Ug*...
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0answers
643 views
Wheatstone bridge and op-amp for a detector
I have a circuit like this to make a temperature detector.
R3 is my thermistor and R3 at 25°C = 10000 Ohms. I chose R4 so that R4=R3 at 40°c = 5000 Ohms.
Do I have to choose R1 and R2 so that R1*R4 =...
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0answers
277 views
Load cell circuit does not work on circuit simulator
I want to simulate a load cell interfacing with AD620 for amplification.
- My load cell is 40 Kg max with 2mV/V sensitivity and 10 V excitation voltage with input resistance of 405 ohm and output ...
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1answer
889 views
INA125P Strain gauge amplification problem
I'm using the INA125P to amplify the strain of a 350 ohm strain gauge in a self-built Wheatstone bridge circuit for measurement. I'm testing using a 351 ohm resistor to mimick a strain gauge under ...
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1answer
87 views
Negative differential to instrumentation amplifier causing problems
I am using a pair of strain gauges to make a weight scale. The strain gauges are the three-wire type that you can by on Amazon or Sparkfun. The strain gauges form a full wheatstone bridge, whose ...
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2answers
149 views
Hook up a load cell with High Level Amplied Output (only input+ input- output+) to load cell amplifer
I have been successfully hooking up load cells (e.g., TAS606, red = E+, green = O+, black = E-, and white = O-) and load sensors (with help from a load cell contaminator ) to load cell amplifer (e.g., ...
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2answers
657 views
resistor value in wheatstone bridge
I have a resistance based sensor which gives the resistance change when the strain/force is applied. How to measure the unknown resistance change using the Wheatstone bridge circuit.? I mean what are ...
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3answers
1k views
How to choose the right amplifier for 100 Ohm RTD in 3 wire configuration?
I have been doing research for the past week on setting up a 100 Ohm Platinum RTD to work with labjack U3 LV (I have to use labjack). I know I have to start off with a wheatstone bridge, and use a ...
3
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2answers
2k views
What is the purpose of the Vref in this opamp comparator circuit?
I am designing a simple circuit for a sensork, and this was an example circuit given by the manufacturer. The sensor is a magnetic sensor in a standard wheatstone bridge arrangement. I was wondering ...
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1answer
471 views
Strain Gauge - Wheatstone bridge DRIFT
I have a 350 ohm bridge with 04 fixed resistors, later on one of them will be replaced by a strain gauge sensor. In the meantime I am trying to understand where the drift is coming from.
This bridge ...
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1answer
610 views
Determining the Transfer Function of a Wheatstone Bridge
I am designing a Wheatstone Bridge, and would like to calculate the transfer function of the bridge input to the bridge output.
The Wheatstone Bridge is designed as follows:
Three of the ...
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0answers
654 views
Strain Gauges Calculation and maximum life
EDITED: Following the mentioned datasheets in the comment I will post an explanation and some answers for correction.
I am having trouble calculating, theoretically, the characteristics of a given ...
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2answers
356 views
Oscillating voltage in Wheatstone bridge
I am using a simple wheatstone configuration to measure resistivity of a material I have.
The problem is that when I am measuring the Voltage (Vg) with a multimetre and it is oscillating(fluctuating)....
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4answers
528 views
How to find area under the curve of a signal?
I am using a Wheatstone Bridge circuit with one pressure sensor. I want to find the area under the curve as the signal goes from 0 to maximum to 0 again. I have tried to use ADC of Arduino and then ...
