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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What are the disadvantages of crocodile (alligator) probes? [closed]
When measuring with an oscilloscope, I use an original high frequency oscilloscope probe and a double side crocodile (alligator) clip and the results are usually very close.
Note: it is called ...
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How to measure Lithium-ion battery SoC?
I have a 48 V 12 Ah Lithium-ion battery pack.
I am struggling in finding a way to measure its State of Charge.
It will be charged through a 13S JBD BMS.
I need to spit out information from the battery ...
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How to Read Unipolar Square Waves on TRMS Multimeter
I'm trying to switch from reading my high-voltage unipolar square wave signal from a benchtop oscilloscope to a handheld multimeter, but I don't understand why my multimeter is giving the voltages it'...
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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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Measure capacitance with Arduino and AD7746
I want to measure capacitance with an Arduino and an AD7746 capacitive sensor.
I already used ChatGPT and some examples, but the sensor measures just 0 pF. When I measure with an LCR meter, the ...
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Resistance measurement with DMMs
I had one doubt regarding resistance measurement from multimeters. I cannot show the schematic because it is confidential but I have added a circuit diagram. It refers to a gate driver circuit.
I am ...
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Comparison of two methods used to calculate capacitance
I need to compare two potential methods used to calculate capacitance, but I can't find the names for them to do some research.
The first method: Placing a capacitor in a circuit with an 800 Hz ...
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Measuring impedance on VNA
Question:
I would like to measure the impedance and phase of an electric piezo tranducer with a resonant frequency of approximately 1MHz - a graph of impedance in Ohms as a function of frequency.
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Measure transformer real power
I’m new at making transformers myself, and the ones that I designed had the correct output voltage, and when they were connected to batteries (previously rectified), they give me a an approximate of ...
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How to determine C-rate for DIY batteries?
I am investigating some DIY battery chemistries and construction, as such they do not have a known C-rate. How would one measure this? How is it determined for commercial batteries? There seems to ...
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Are there any tricks for measuring high voltages (~1000 V) efficiently?
The simple way to measure voltages above VDD is to use a resistor divider. However, once you get into the 100s of volts these dissipate significant power.
For example, one of my current designs ...
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Uncertainty for measuring a resistor
I am trying to calculate the uncertainty of a measure on a resistor. The expected value of the resistor is 45 mΩ. For measuring the resistor I used the two following instruments:
SM500-CP-90
Agilent ...
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Capacitor test mode in ICT
My ICT machine has two capacitor measurement modes on the PCB:
Mode 1: Use DC source test method (Figure 1)
Mode 2: Use AC source test method (Figure 2)
Could anyone please help me with the ...
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Which is the best method to measure AC voltage?
I am trying to make a UPS circuit. I need to have a high speed measurement for the input AC voltage (220 Vrms) (in order to know whether to turn on/off the inverter). I had tried using this circuit:
...
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What could be the possible reason for waveform distortion while connecting differential probe GND with single ended probe GND?
I am measuring following waveforms using a DSO:
Case 1:
Waveform 1 wrt GND using differtial probe.
Waveform 2 wrt GND using single ended probe.
Result 1: Waveform 1 distorted.
Case 2:
Waveform 1 wrt ...
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How can I find the diameter of a wire if I have the length and resistance? I cannot use measuring tool because wire is thinner than 0.1 mm
As the title suggests; I am trying to calculate the diameter of a wire given its length and resistance.
Specifications:
Length: 30.4 cm
Resistance: 17 Ω
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