Questions tagged [shunt]
Electrical shunt -- relating to a small resistance usually used to sense current. This is what your multimeter uses to measure current. This tag does not cover magnetic shunts.
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Shunt regulation - discrete or linear?
This is a spin-off of the question I've asked before. I've received many interesting answers and summarized them there. I also accepted most interesting suggestion. During this time we also bought and ...
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Why would you ground your live terminal shunt resistor
I have seen some wiered things when taking the current measurement from a shunt resistor.
For instance the below circuit
simulate this circuit – Schematic created using CircuitLab
What is the ...
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Choosing a current sensing resistor for boost converter IC AZ34063U
I'm looking to build a boost converter using the AZ34063U IC (Datasheet) and the example circuits in the datasheet use different values, ranging from 0.22 to 0.33, and I couldn't figure out how I ...
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Biasing AC signal - which circuit is the best?
I've seen a similar question asked earlier here:
How do I bias an AC signal for sampling?
However, I have a 3 different circuits and I am not sure which one works best!
I have: +-2V AC signal of ...
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Why is the shunt field of a DC starter-generator disconnected when used as a starter?
The Lycoming T53 turboshaft engine is started using a starter generator. The starter generator is a shunt generator. When the T53 is started, the starter generator is used as a DC motor to get the ...
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Zener Transistor regulator cascaded into 3-pin IC regulator
So I have a 48 V supply and want 5v output at sub 100 mA. The 78L05 is a super low cost 3-pin voltage regulator, but has a maximum input voltage of 30 V.
I was wondering if it is a cost effective / ...
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Calibrating a high current shunt resistor
In a circuit I'm developing I have a shunt that is used for current measurement of +/- 80A. How can its calibration be done? Suppose our budget for this can be 1000 to 1500 USD, what would be the best ...
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External voltage reference MCU RP2040 - Use of series reference?
I designed a board that uses the RP2040 Pico for its ADC and I/O.
To improve the ADC of RP2040 I wanted to use an external reference. In the past, for other projects, I used as external reference a ...
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Shunt's thermal EMF (Seebeck effect) vs Kelvin connection?
While reading this Vishay document about shunts, I saw that temperature mismatch between the shunt's terminals can introduce a "parasitic" voltage drop which will in turn affects the current ...
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What is the benefit of using a 10MΩ resistor in parallel with a current shunt?
I am reading the Operators Manual for the Fluke 8588A Reference DMM and came across this:
The DCI Ext Shunt function provides a calculated current reading for a specified current shunt by measuring ...
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Can I use this voltmeter / ammeter without the shunt supplied along with it?
I bought this voltmeter online.
It does not show current.
Do I need to use 10 A load for some reading or it will work for lower amps also like 1 to 2 A?
From the product details:
Measure Current: ...
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Measuring current with a microcontroller
I'm doing a project that involves sensing current. I'm charging a battery and I need to control how much current and voltage I'm giving out.
I thought that it would be okay to use an SCR like a 40tps ...
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Typical resistance of an SMD solder joint
Do you have an idea of the typical resistance between a PCB track and a SMD resistor pad? That is, the resistance of the solder on, for example, a 0402 resistor.
The idea behind my question is that I'...
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How does a microwave oven transformer shunt help resonate the voltage doubling capacitor?
I was reading this great answer by Neil_UK, and a comment-question was:
Comment Question 1
Are MOTs belonging to the general type called "Leakage/stray field transformer" ?en.wikipedia.org/...
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Why do these INA240 current shunt amplifiers keep failing?
We have over 100 current shunt amplifiers (Texas Instruments INA240A2-Q1 and INA240A3-Q1) monitoring durability testing of brushed DC motors (more specifically, fuel pumps). On our test boards, there ...
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How to compensate for shunt resistor thermal drift? [closed]
I'm working on a electronic load and below schematic is the simplified version of it.
simulate this circuit – Schematic created using CircuitLab
The problem is the thermal drift in resistors ...
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Control scheme to regulate Vin using a Buck regulator
I am trying to create a control scheme that allows a buck regulator to regulate its input voltage instead of its output voltage. I'm trying to make an efficient shunting regulator. My current approach ...
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Connecting the GND of an isolated circuit to the positive side of a 450V transformer output
I moved to a new company that makes very big old-style controlled rectifiers. They asked me to make a new modified, and enhanced thyristor-controlled rectifier. The strangest problem I faced is that ...
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Amplifying millivolt signal to volts from shunt resistor for current detection: Single supply or dual supply op amp?
What are the pros and cons of configuring an op amp to be a single supply op amp vs a dual supply for amplifying very small signals? I am using three of the OPA177GP op amps to build a 3-op amp ...
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Why diode in parallel with shunt resistor?
I would like to know why diode is used in parallel with shunt resistor (Current sense).
I am assuming it is to protect a shunt resistor if voltage drop is more than 0.7 (Vf of diode) in case of high ...
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Current sensing resistor placement [closed]
I will be adding a current sensing resistor to a Buck-boost DC-DC converter. Based on the IC datasheet, the resistor is placed at the low-voltage side next to the power inductor.
But, as far as I know,...
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How to measure current up to 1000A and not go bankrupt
I need to measure current going through my PCB, which can be anything between -1200A to +1200A. Accuracy within 1-2% with bandwidth of anything higher than 50kHz.
The conductor is decided by now - I ...
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Where should I position my shunt resistor?
I am measuring sun irradiance captured on several small solar panels.
The power generated from the panels is not consumed;
The measuring device is independently powered;
My focus is on high-precision ...
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How to calibrate a shunt with a MM and another shunt
I had noticed someone in my lab calibrated a shunt with a MM and another shunt, was wondering how they went about this?
Thank You
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Replacing current shunt resistor with different value. Is there a problem?
I have Nitecore UM2 (2 slot) battery charger whose current sense/shunt resistor of 0.1 ohms R100 (package 1206) blown. I replaced with working slot to see if everything works good and it is.
I am ...
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Why add extra resistance to a shunt?
simulate this circuit – Schematic created using CircuitLab
I'm using a Fluke Y5020 air cooled shunt (it's 10 mΩ, 20 A max) and putting 3 A at 60 Hz into it.
Aside from Ohm's law, is there any ...
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Preventing mains spikes from cheap water pump
I bought a pack of add-ons for my DIY CNC that has a water cooled spindle.
One of the items was the water pump. But when I switch on the pump, a fairly substantial crack can be heard in any speakers ...
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What are these PCB calibration standards?
I found these shunt resistors in a paper that uses them to calibrate AC equipment for EIS testing. They used the "frequency dependent complex impedance response" of these standards to ...
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Shunt resistor between differential lines before differential amp
I wonder that why is the shunt resistor used between differential lines?
After I took a look the schematic of VR sensor interface, they suggest me to put shunt resistor. The shunt resistor can prevent ...
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High Current (100A) Shunt resistor mounting method
In my design I want to measure the current going through a load with a shunt resistor. Based on some preliminary calculations, I've selected WSBS85181L000JK34 from Vishay. Being my first time using ...
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Component selection in high side mains current measurement
I need to measure relative small currents (10 mA to 500 mA) from the high side at mains voltage (230 VAC RMS) levels. I also need a high resolution and preferably high accuracy for the measurement. ...
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What circuits can blink an LED at certain power consumption threshold?
I have never designed an analog circuit and I am requested to design an analog circuit where a LED driven by a transistor must start blinking at a given frequency when the input power is above a ...
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Better design for a shunt resistor load on a voltage divider
A bit new to circuit design.
I'm designing a helper circuit that monitors incoming current. For testing purposes, we'll be taking inputs of max ~5 V and dropping this down to the millivolts, and pass ...
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High side current sensing amplifier placed on low side. Possible?
I am trying to build a custom 12 volt battery current sensor for my car as a little hobby project. I want to place a shunt on the negative side of the battery, and get the measurements from there and ...
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Voltage Shunt regulator NCP431
I'm trying to figure out how the voltage shunt regulator for my case is working. Below an extract of the electronic schematic of an isolated flyback board Ref NCP11187A65P45WGEVB from OnSemi which has ...
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Isolation problem in AC current sensing circuit
I am working on an electronic project where I have to measure AC current. While searching, I often encountered a term called "isolation", especially when using the shunt resistor. What is ...
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Shunt resistor for AC current measurement
I am working on a power meter project where I want to measure an AC current using a shunt resistor. After research, I found that the use of this resistance is rarely. Is it possible to know the reason ...
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Shunt FET PWM best practices?
I am designing an LED driving circuit using an AL8861Y-13. Like any switching regulator, its PWM resolution/frequency are limited.
I want to do higher frequency and resolution, so I have opted for a ...
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Op-amp gain not working as expected
I'm trying to amplify a really small (1.3 mV) voltage from a sense resistor. I am using the following schematic:
My load is an LED and resistor. For R2, I'm using a 470 kΩ resistor. For R1, I'm using ...
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Current shunt resistors for different voltages
Are current shunt resistor values usually based on the max. current that will be seen and the smallest amount of current change that can be detected?
I'm wondering if the current shunt resistance ...
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How to account for additional series resistance of SMU for characterising solar cells?
I have been building a source-measure unit based on a design similar to the DC2591A. I unfortunately cannot share the design, but largely it replicates the DC2591A using slightly different components ...
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Current shunt not working
I was using a 12 ohm current sensing resistor and I was getting 26mVAC across IN and IP.
When I switched to a 100mohm resistor then I was getting around 8.2mVAC across IN and IP
Load = 300W and ...
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Resistive current sensor shows reading when I connect it in series with a battery while no current is flowing through it
I need to monitor the charge and discharge current of two 12V lead-acid batteries in series using an INA219 current sensor, and a 0.75 mOhm shunt. At first, I placed the current shunt in the low side ...
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Feedback impact of collector-base shunt resistor in common emitter amp stage
I made this 3 transistor Rf amp which works well at 10 MHz and has 50 ohm output impedance, a gain of 8.2 (18.3 dB) and quiescent curent of 28.6 mA. It consists of a common emitter stage followed by 2 ...
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CSA - Pulses on the output of the low side current measurement amplifier
I'm a bit lost at the moment, since I see pulses on the output of my CSA and I cannot really see, why this happens.
The pulses occur immediately, when I apply a PWM signal to the gate driver (...
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Current Shunt Amplifier Problem (MAX49921)
I'm currently trying out the evaluation kit for the MAX49921 from Maxim, and I'm having a few problems with it. First thing to note is that my board appears to be an issue a board, but all the ...
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Can I use a normal diode as a Zener/Varistor ? If not, why not? (focus on Varistor use)
When I look at a normal diode graph like that I see the Vz Zener voltage of it looks just like a Zener, so why not using it reverse biased like a Zener? I ask like that because I never saw it being ...
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Current measurements - shunt switching
I have been designing a current measuring device, and since it requires high wide-range accuracy, I decided to use two shunt resistors of different sizes. The schematic is shown below:
The design ...
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Shunt both op-amp input terminals individually
I'm working on a lab project for my class. My manual says that I need to shunt both OPAMP input terminals individually with resistors Rx = 1kΩ.
I'm not sure what that means.
Where should I put the ...
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Shunt voltage direction circuit [closed]
I need to know which terminal of a shunt is higher, ie whether I'm charging or discharging my 12v battery bank. The voltage difference is very small (max 74mv) since the current flowing may be tiny, ...
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