Questions tagged [measurement]
Measurement is the assignment of numbers to objects or events. All measurements consist of three parts: magnitude, dimensions (units) and uncertainty.
1,118
questions
2
votes
0
answers
82
views
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 ...
- 69
2
votes
1
answer
74
views
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 ...
0
votes
1
answer
49
views
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'...
- 69
6
votes
4
answers
749
views
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 ...
- 1,031
0
votes
3
answers
105
views
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 ...
- 43
0
votes
2
answers
65
views
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:...
- 11
3
votes
2
answers
104
views
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 ...
- 14.5k
0
votes
2
answers
51
views
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 ...
- 215
0
votes
0
answers
28
views
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.
...
0
votes
1
answer
22
views
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 ...
0
votes
1
answer
45
views
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 ...
0
votes
0
answers
14
views
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 ...
4
votes
3
answers
835
views
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 ...
- 41
0
votes
2
answers
85
views
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 ...
- 113
6
votes
4
answers
204
views
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. ...
- 409