Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

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.

An electrical shunt is a very (comparatively) small resistance, the main purpose of which is to sense the current flowing through it, by sensing the voltage on a fixed resistance. Often used in power electronics as part of regulation of the output voltage or current, it can also be used to merely "read" the current for recording purposes, as in what your multimeter uses to sense current.

This tag is intended for only electrical shunts, and specifically does not relate to magnetic shunts.

266 questions
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Why this small cut in Ampere meter shunt?

I have seen lot of ampere meter shunt like this. What is the reason for this small cut?
user_fs10
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What are the advantages of a shunt resistor vs. a hall effect sensor?

I'm constructing a boost converter, and I need to measure both the input current and the output current. Currents range anywhere from 25A to 200A, depending on the model. My controller is referenced to the negative rail of the converter. I've been…
Stephen Collings
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Why would a current measurement shunt design use 4 sense pins?

I am interested in low resistance shunts (tens / hundreds of microohms range) used in high voltage / high current setting. Typically, those are busbar-mounted shunt resistors like this one: The current is passing through the busbar and the shunt,…
Dainius Stankevicius
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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 will use a copper bar. The original plan was to…
TQQQ
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Measuring average current with uC and current shunt

This is my first post. I'm a software guy trying to do hardware so be gentle :) Circuit I'm designing a small circuit (see pic, and sorry for messy schematic) that plain and simply is a bunch of MOSFETS and gate drivers designed to switch resistive…
ltj
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Measure wide range of current 800 µA - 1.5 A

I am having difficulty measuring current into an IoT device that I am making. I need to be able to gather data about power consumption over time, and about the sleep mode current. I was trying to use a shunt resistor to gather the current data, but…
Reid
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Shunt resistor, what value should I expect when soldering on PCB?

I am using a 10 mohm 1% shunt to measure current via voltage drop. My circuit is on a breadboard... It behaves as if the shunt has a value of ~30-40 mohm instead of 10 mohms. I double checked this by sourcing the current through the shunt alone and…
Tony
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Do you have to use an instrumentation amplifier to measure voltage across a 0.01 ohm shunt?

I was planning on implementing a current sense feature on the STM32 Bluepill to measure the current output of a solar panel (150 mA short-circuit current, 14 V Open-circuit voltage) using LM358 single-supply op amps and a 0.01 ohm shunt. No matter…
A.H.Z
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Why cap across shunt resistor, input bypass caps and small resistors on current sensing inputs?

I want to build a sensitive current sensing circuit using shunt, and since I also repair MacBooks occasionally, I have some contact with the schematics of real working expensive devices (although whoever follows Louis Rossmann, knows there are…
Ilya
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What causes inaccuracy over time on a DMM?

Here is a piece of information from a datasheet of a DMM. The accuracy rates seemed interesting for me. I wonder what causes difference in the accuracy, especially the changes after 24 hrs? Is it only shunt related, or another components related…
Angs
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TL431 Constant current source

I have few doubts regarding TL431. Please correct if i am wrong.. TL431 can be used to generate voltages from Vref to 36V. Output voltage is taken across diode in reverse biassed condition. reverse characterstics says Reverse breakdown voltage is…
user19579
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How do I amplify the difference between two voltages?

Starting at the beginning: I have a shunt that carries DC current, and the voltage drop is very slight. I want to amplify it in order to see it better on oscilloscope, and to have it scaled correctly for e.g. an Arduino ADC. This to measure the…
Thomas
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What is the purpose of clamping the gate and source of a mosfet

Is clamping the gate and source of a MOSFET really important? I have seen this in some articles and some datasheets of MOSFETs where they have built in clamping. As far as i know they are used for ESD. Asuming that the gate is just a trace to a…
Jake quin
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5
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4-terminal shunt resistor

What is the importance of a 4-terminal shunt resistor? What is real purpose behind using two seperate terminal for the voltage measurement across the shunt resistor?
IamDp
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How to measure car battery current precisely in wide range (starter current, charging)

I want to measure car battery currents in high resolution and in wide range and both directions (including engine start and charging currents). I don't need very high precision measurement, but I want high resolution. I decided to use large…
Kamil
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