Questions tagged [measurement]
Measurement is the assignment of numbers to objects or events. All measurements consist of three parts: magnitude, dimensions (units) and uncertainty.
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Using 50 Ω coax cable instead of passive probe
Preface, why am I asking this question?
Instead of using a passive probe with a ground clip, I want a more "permanent" and reliable connection for my measurements. Note: I'm not talking ...
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How to measure multiple resistances with Arduino Uno, without one measurement influencing the other?
I'm working on a project where I aim to measure resistances using an Arduino Uno. I started with two separate voltage dividers, each using a 1 MOhm reference resistor, connected to a common Arduino ...
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What is the real resolution of my voltage measurement when I use only some of the range of of the ADCchannel
I have a 16 bit ADC, I use the +/1 V range, differential channel. If I used the full range of the ADC to provide full resolution (I am aware non-linearity and noise may affect this) this calculates as:...
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My isolation transformer has its protective earth connected to the output neutral. How should I rewire it for my home lab for "DUT probing"?
I have a rather sturdy isolation transformer in my home lab and I just realized that the primary side earth is not only connected to the output side earth but also to the output side neutral. I don't ...
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What does an accuracy of 0.1% + 20 mV mean in a power analyzer's data sheet?
I need to know the measurement accuracy of Keysight N6705C power analyzer. I came across this document (N6700 Modular Power System Family.pdf) that states the error in terms of a percentage plus a ...
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Understanding Voltage Read in Voltage Divider for NXP S32K118 Microcontroller ADC
I am having a bit of a hard time understanding the voltage read in the voltage divider that is being an input for an ADC to an NXP microcontroller, S32K118. Below is the schematic of the circuit.
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Determining Suitable TRMS Voltmeter Specs for Modulated Signal Measurement
I'm seeking advice on selecting a TRMS (True RMS) voltmeter suitable for measuring the voltage across a resistor with a modulated signal. Here's the scenario:
I need to measure the TRMS voltage across ...
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Induction motors torque measurement
I am to calculate the running efficiency of a 3-Ph squirrel cage induction motor. I have the rated data for the motor. I have the load speed of the motor but I need output torque to calculate the ...
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Pulse width modulation using ML4800CP
I am working on a SMPS (450 V output). It use an ML4800CP IC to control and manage 450 V DC.
How can I measure the PWM signal using an oscilloscope? I attached it, and it worked well for the PFC ...
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Measuring nA leakage current
I'm trying to measure some leakage currents of both a diode (expected around 5 nA) and a MOSFET (20 nA).
My issue is my meter's measurement accuracy is only around 10 uA, and I need an accurate ...
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Why might my circuit's measured voltage drop when I add more load to it?
I have one of these power supplies:
I also have an MCR-4V data logger:
If I connect wires directly from the power supply to the data logger (red to red, black to black), then the voltage output on ...
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Mass paralled resistors for better tolerance [duplicate]
I hope this doesn't get people's eye rolling as a very rudimentary question...
Here goes. I need a very, very precise resistor divider, say a 1/11 ratio. It doesn't really matter the ratio chosen. ...
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Are LCR meters sensitive enough to measure PCB trace impedance? [closed]
How long is a piece of string?
I’m working on an application currently where trace impedance appears to make all the difference on performance as observed on a few unguided experimental revisions of ...
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How "Zero" is this supposedly Zero-TCR resistor? And how much better is it than this other one?
I found a resistor at Digikey, and the TCR was quoted as being 0.0ppm/°C, and I had to check the datasheet just to refute my suspicion that it was a data entry error, and it looks real, but just how ...
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Can I measure the internal termination resistance of a MIPI receiver?
This question is further to: How accurate are internal terminators on chips with high speed differential inputs?.
I would like to measure the actual termination resistance inside one of these chips (...
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