Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [current-measurement]

Measurements of the current flowing through a circuit

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How do I measure 10,000 A DC?

What is the standard way to measure a current of about 10,000 A? DC clamp meters seem to have only scales up to 2,000 A. Edit Some background of this question: I am a high school physics teacher and I am trying to improve some classical experiments…
Julia
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Is there an implicit "unit of time" involved in electricity measurement? (e.g. miles per hour, kb per second, amps per ???)

I'm very new to electronics and I am going through what must be a common difficulty in grasping voltage, current, and resistance. I'll restrict my question to current as I suspect understanding that piece may shed light on voltage and…
Cliff Pruitt
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Why use an input resistor in this current sense circuit?

In the Linear Technology AN 105 on current sensing one can find the following circuit. I am wondering what the purpose of the 200 ohm resistor on the inverting input is. It appears to have no effect. Note that in the following paragraph a virtually…
Max
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How to measure small, spiky amounts of current?

Let's assume I have a microcontroller with some amount of peripherals attached and would like to be able to make a reasonable estimate of battery life. Because I might have it sleep at times, and various peripherals would be in differing states, my…
David
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Ways to measure current in picoamperes

I need to check the low power consumption of a microcontroller in the range of picoamperes. I only have a multimeter capable of measuring milliamperes and as such it shows 0. Is there an easy and precise way to measure picoamperes?
Tedi
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How is this ground fault circuit working?

I am having a difficult time understanding a few things in regards to the ground fault detection circuit below. I have found this circuit while investigating ground fault detection. I intend to build my own circuit for use in my system and am using…
Jason
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Measuring current over longer period of time

I'm in the process of building a device based on the Espressif ESP32. The device will spend most of its life in deep sleep. With a simple multimeter I've been able to determine that it's using 0.25 uA while in deep sleep. The device is running out…
ErikL
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Use a current monitor IC or roll my own?

I'm looking to measure current consumption of my microcontroller as an in-built feature of the final design. Should I buy and use high-side current monitors that are available on the market (e.g. Zetex ZXCT1009)? Or is it possible to build one out…
cksa361
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Is there a simpler solution for highside current sensing here?

I have an existing automotive circuit simplified in the image. The loads (2 or more solenoids in parallel) share a 12V supply and are individually switched to ground through the car's ECU. I need to detect when any one of the circuits close (only…
Jon
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Can I measure current with a 0.1Ω shunt?

I am currently trying to make a game console out of a Raspberry Pi 4 and a hard drive, with an Arduino to control boot, shutdown or reset, plus temperature. I got a degree in engineering in electronics and embedded systems, however I could not…
Varech
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Measuring small currents over a small sense resistor

I have been having some difficulty recently when trying to measure very low currents when using a small sense resistor. I am trying to measure in the range of uA (1 - 150uA) with a supply voltage of 3.3V. Now, usually this is not too much of an…
MCG
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What determines the frequency range of a current transformer?

Per the title, what physical or construction parameters determine the frequency range of a current transformer? I happen to be looking at these two from mouser, but I'm sure the question is generic enough to apply to a large number of these…
ljwobker
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Common Mode Voltage on Current Sense Amplifier (direction of current)

From reading some threads here I understand that the Common Mode Voltage of a Current Sensor Amplifier when measuring high-side is the average of the positive and negative input pin. In my application I would like to measure the current in both…
Tom L.
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Why not use a diode instead of a resistor for current sense circuits?

We're building a motor-drive circuit using an L6206 dual H-bridge circuit. The bottom side of its H drivers come out of a pin called \$V_{sense}\$, intended to be connected to ground or to a low-side current-sense circuit. I'm expecting to drive…
SusanW
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AD8217 High Side Current Sensor Output at Low Currents

I am using an AD8217 high side current sensor to measure currents up to 20A. It works as expected when testing with lower currents and sense resistors of 1\$ \Omega \$ and 0.3\$ \Omega \$ and currents of 660mA and 130mA. For the eventual 20A, I…
Mitch
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