Questions tagged [wheatstone-bridge]
A circuit to measure an unknown resistance.
210
questions
0
votes
1
answer
63
views
Very irregular reading of load cells with the hx711 (on an ESP32)
I'm using an ESP32-S3-WROOM-1U and a four load cells, connected in a full Wheatstone bridge to an HX711 to read the weight of an ...
- 133
0
votes
2
answers
47
views
Wheatstone bridge to voltage follower circuit not working as expected
I am designing the following circuit shown in the atached image. It is a wheatsone bridge with the differential output attached to voltage followers on each terminal and then connected to a single ...
- 1
2
votes
1
answer
119
views
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 ...
- 155
0
votes
1
answer
131
views
How can I apply Kirchoff Law for a capacitor in Wheatstone Bridge?
I got this question in an exam, where I was given an unbalanced Wheatstone bridge and was asked to find the voltage across the capacitor. I can't understand how to apply Kirchhoff's laws for a ...
- 13
0
votes
1
answer
63
views
How do you compensate for a varying DC offset when using a wheatstone bridge?
Background
I have a sensitive magnetic sensor that is packaged as a wheatstone bridge with a 20k
device resistance. I am using it to measure the rotation of a magnet. It is possible to calibrate out ...
- 101
0
votes
4
answers
366
views
Wheatstone Bridge with Instrumentation Amplifier
I have set up this circuit:
I measure an output of 0.61 V from the instrumentation amplifier. The gain of the amplifier is set to 21. The formula for the output is given by:
Uout=(1+2R1/Rg)×(R3/R2)×(...
- 41
1
vote
0
answers
30
views
Online motor inductance measurement at different rotor angle
I wanted to measure the inductance of PMSM at different rotor angles. I'm familiar with the offline methods of measuring motor inductance but would like to measure a motor's inductance while it's ...
1
vote
1
answer
91
views
Analysis of Wheatstone Bridge circuit with connected output terminals
I am given the following case of a Wheatstone Bridge circuit where the output Terminals \$U_{a}\$ and \$U_{b}\$ are connected with a wire and need to derive both output voltages as functions of the ...
- 21
3
votes
0
answers
66
views
Determining resistors in a Wheatstone Bridge from Ohmmeter readings - Unsolvable system of equations
I have been challenged in an assignment that uses a Wheatstone bridge to find values for the resistances in each arm, given that they are 1 kOhm +- 1%, and using only Ohmmeter readings and short-...
- 31
0
votes
1
answer
47
views
Help testing Pressure Sensors
I have a few ME600 Metallux sensors that I harvested from some discarded products. I want to build a project with these but would like to verify they work before getting too far. From the datasheet ...
- 1
0
votes
1
answer
478
views
Unbalanced Wheatstone bridge with a capacitor in the middle
I have to find the amount of charge stored in a capacitor after a significant amount of time when $$ R_{1}=1 k \Omega, R_{2}=8 k \Omega, R_{3}=4 k \Omega, R_{4}=2 k \Omega,C=1\mu F,V=10V$$ There is no ...
- 407
-2
votes
2
answers
69
views
How do I find the value of resistor 4? [closed]
Assuming this is balanced: if R1 is 130 Ω, R2 is 240 Ω, and R3 is 65 Ω, then what is R4?
0
votes
2
answers
71
views
Pressure sensor output not clear from datasheet
Planning to use the following sensor:
https://shop.bb-sensors.com/Druck/Drucksensoren/
Part number SHOP 0391 0004-02M.
I am planning to give 3.3 VDC to sensor. Pressure input will be 0 to 10 bar. It ...
- 75
2
votes
2
answers
281
views
Total resistance of circuits that resemble Wheatstone bridges
I need to find the total resistance that is seen from terminals a and b for the three circuits below.
I found that all of the circuits have the same total resistance Rt=R (not sure if the answer is ...
- 407
1
vote
1
answer
157
views
Superposition theorem for a Wheatstone bridge
I'm applying the superposition theorem to a Wheatstone bridge. I attached the picture. In this circuit there are two voltage generators: the first/top one is replaced by a wire. That's why there is a ...
- 27
0
votes
0
answers
58
views
Am I wiring this sensor / wheatstone bridge correctly?
I have a methane sensor (MP7227-DA) that gives the following schematic:
I've assumed R1 and R2 = (C) and (D) in the diagram, R3 and R4 are resistors which are equal and make up the other side of the ...
- 101
0
votes
1
answer
60
views
Constant temperature operation of microheater
I have been trying to make a constant temperature control for microheaters based on this wheatstone bridge circuit, using a trim pot to set the temperature setpoint. The purpose is to keep the heater ...
- 1
0
votes
0
answers
332
views
Read 2-wire or 3-wire temperature sensor by unique connection to Arduino
I have 2 types of temperature sensors, 2-wire, and 3-wire RTD
I look on the internet and I've seen many schematics use the simple voltage divider for 2 wire sensors and the Wheatstone bridge for 3 ...
- 305
0
votes
1
answer
88
views
RTD - convert measured voltage to temperature
I have a 3-wire RTD connected to a Wheatstone bridge and then to a INA. The Vout from the INA is then connected to a ADC. How can I convert the measured voltage from the ADC to the respective ...
- 11
0
votes
2
answers
161
views
Wheatstone bridge resistance and sensitivity tolerances
A pressure sensor datasheet gives its resistance as 5 kΩ +/- 1 kΩ or 3.5 kΩ +/-0.5 kΩ (optional version). The full-scale output is 150 mV +/- 30 mV at 100 psi, 5 V bridge voltage Vb.
The way I imagine ...
- 817
1
vote
1
answer
77
views
Wheatstone bridge with zero offset voltage
Can I power a Wheatstone bridge circuit with a positive voltage (say +5) on one side and negative (-5) on the other, such that the output common mode voltage is at 0V? I don't see any reason why not, ...
- 31
1
vote
0
answers
86
views
Wheatstone bridge analysis
Hello,
I am facing issues in calculating few parameters for the following information. I am new to this concept of strain gauge, wheatstone bridge, and data acquisition system
Four resistive strain ...
- 11
1
vote
2
answers
108
views
Puzzled by op-amp behavior in a temperature controller circuit
I have been trying to make a temperature controller based on a closed-loop control utilizing a Wheatstone bridge configuration and an op-amp. The temperature setpoint is adjusted by a trimpot. The ...
- 31
1
vote
1
answer
73
views
Sense small variations in inductance in AC for a metal detector circuit
I am currently working on the design of a metal detector circuit. I am relying on the method that the coil's inductance would change when a metal is close to it (due to eddy currents.) I have tried ...
- 179
8
votes
2
answers
2k
views
What is the point of a Wheatstone Bridge?
What is the point of a wheatstone bridge? Everywhere, like here says that it's used for measuring an unknown resistance, but I don't understand why it's so complicated.
Can't you just use a voltage ...
- 299
0
votes
2
answers
283
views
How to get R_THEVENIN in Wheatstone bridge?
In the simplification of a Wheatstone bridge with Thevenin's theorem when we calculate the RThevenin as in the schematic. How to explain in another way that the resistor R1 and R3 are in parallel and ...
- 27
1
vote
1
answer
255
views
3 wire RTD configuration Wheatstone bridge Vs. Constant Current Source
I am trying to design a 3 wire RTD circuit. I've been looking into either a Wheatstone bridge or a constant current source with ratiometric measurements. I would like to know which is the better ...
- 11
1
vote
1
answer
120
views
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 ...
- 139
1
vote
4
answers
329
views
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 ...
- 91
0
votes
1
answer
320
views
Power consumption in a Wheatstone bridge
Q1) Explain how the power consumption of each resistor will change as the resistance of Rs increases.
A) It is a circuit in which parallel connections of R1 and Rx and parallel connections of R2 and ...
- 99
3
votes
3
answers
393
views
Op-amp - minimal differential voltage?
I want to implement a PT100 sensor measuring circuit using a Wheatstone bridge. Below is a link to the implementation that I suggested.
https://www.instructables.com/Measuring-Temperature-Using-a-...
- 61
1
vote
3
answers
438
views
Wheatstone bridge current consumption
How would you calculate the total current consumption of a Wheatstone bridge made of four 350 Ω resistors, with a supply voltage of 1.8 V? And what is the theory behind this "resistor combination&...
- 23
2
votes
1
answer
186
views
Question on INA122P non-linear gain
I am trying to apply gain for a 0.0 - 16.7 mV signal with an INA122P, with a single 10 V supply for all the circuits, with Vref driven at 0.0 mV.
Here is the circuit that I am using, no Rg applied, ...
1
vote
1
answer
69
views
Asking experience for this flow-through pressure sensor: 26PCAFG6G - Honeywell
I have the following sensor:26PCAFG6G
The output of the signal is a differential output from a Wheatstone bridge with 0 - 1 psi, or 0 - 70.3 cmH20 corresponding to 0 - 16.7 mV, I am using AD623AN for ...
0
votes
0
answers
118
views
Low power Wheatstone bridge
I'm working on a low-power application (cycling power meter) that will use a Wheatstone bridge in half-bridge configuration to measure strain. I'd like to run this system from a coin cell (or ...
- 27
0
votes
1
answer
153
views
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 ...
3
votes
1
answer
119
views
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 ...
- 63
0
votes
2
answers
131
views
Am I overloading my circuit?
I'm using op-amps as schmitt trigger and with the resistors in the wheatstone bridge I am trying to control the flow of current in the load. When the load resistance is not connect between the outputs ...
3
votes
5
answers
579
views
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 ...
- 63
2
votes
0
answers
80
views
Ratiometric AD conversion with high excitation voltage
Still working on a Wheatstone bridge sensor (a load cell); for reasons unknown it insists to be excited with at least 8V (manufacturer gave no assistance, simply state 10V as nominal excitation)
...
- 8,271
-1
votes
3
answers
102
views
Wheatstone bridge
I need help with solving the following Wheatstone bridge circuit.
I don't know the value of the resistances nor the capacitor.
Where or how do I get started to calculate them?
The variable resistance ...
1
vote
1
answer
103
views
Is it possible to connect a Vin to a ref of an instrumentation amplifier?
I have a circuit in which I need an instrumentation amplifier (INA128 (datasheet)) to be connected correctly for it to work. I don't know if it needs another resistance or if the input needs to be ...
0
votes
1
answer
97
views
Can I drive a bridge sensing circuit with a voltage reference?
On the specification sheet there is this application circuit where the sensing bridge circuit is driven by the same voltage reference IC that sets the voltage reference (REFP) of the ADC.
I remembered ...
- 1,400
2
votes
2
answers
1k
views
How to improve HX711 to feed two or more load cells in parallel?
HX711 datasheet
Load cells I'm using
I have typical load cells and want to connect them in parallel directly to the HX711 "A" section of the amplifier.
The load cells have an input ...
0
votes
2
answers
482
views
How can I calculate the values of the four resistors in a Wheatstone bridge?
I measured black-red = 400ohm, green-white = 350ohm in a 5kg loadcell.
How can I calculate the resistor values?
1
vote
1
answer
868
views
How to read four load cells with a single ADC input?
I am currently using strain gauge based load cells and want to weigh 1-5kg granular products on whatever container with 4loadcells beneath. I encountered a problem with connecting load cells in a ...
0
votes
1
answer
87
views
how to calculate the output voltage of specific circuit using superposition law
Hi, How to calculate the output voltage of the circuit is shown below. Using the superposition principle is the best or the one that you recommend. I'm using strain gauges based on the Wheatstone ...
3
votes
1
answer
197
views
How does temperature compensation work for pellistors in Wheatstone bridge?
Pellistors are used to detect combustible gases. Basically, the gas is burned inside the pellistor and the heat released will change the resistance of the detection element. The concentration of the ...
- 309
3
votes
2
answers
219
views
Is there an affordable way to balance a bridge without using expensive resistors?
I have a full and balanced bridge circuit with four through-hole \$ 350 \,\Omega \$ resistors and an instrumentation amplifier AD8293G80 that has a gain of 80. Both the bridge and the amplifier are ...
- 1,400
3
votes
2
answers
801
views
LM358 Differential Two Stage Amplifier Misbehaving (unanticipated output voltages)
Hello all and thank you in advance for taking a look at my problem.
I have made a circuit which takes a differential voltage from a Wheatstone bridge (pressure transducer) and converts to an analog ...
- 51