Act of measuring voltage

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3
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2answers
128 views

Measure high voltages with a multimeter

My multimeter is rated to 600V. How can I readily (and safely) use it to measure higher voltages?
0
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1answer
91 views

Using op amp to measure battery voltage

I have a question regarding the usage of op amp to measure battery voltage. I know there are battery gauge IC's dedicated for that, but I'm trying to do this to both understand the op amps better and ...
0
votes
1answer
17 views

Signal offset using FRDM-KL25Z

I am developing a voltmeter using FRDM-KL25Z and I needed a voltage divider with a 1.65V offset, and here is the circuit I am using: Does the offset work well? Is there any other (easy) way to do ...
3
votes
4answers
246 views

The potentiometer used in electronics is not a measuring instrument. Why it is called a meter?

Why this kind of variable resistor is called a "meter", when it is not a measuring instrument? I have seen another instrument of same name. In our school physics lab, there was a big rectangular, ...
0
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2answers
112 views

How to combine LED and voltage divider

I want to detect the presence of a 8.4V voltage source from an Arduino, so I'm using a voltage divider to step it down to a voltage safe for the Arduino to read with an digital pin. However, for when ...
0
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2answers
53 views

Question about multimeter resolution

So i got a multimeter from a friend for free. This is the one: Multimeter Info In the manual of the multimeter it says that the lowest resolution of DC Voltage is 0.1 mV. does that mean that i can ...
0
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3answers
57 views

Multiple voltage measurement

I have to measure voltage for about 100 different channels in one object and the problems is space for equipment (100 transducers would require lots of space) and price of transducers. Is there a way ...
0
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2answers
41 views

If there's no current through a battery, can it supply a voltage drop across a resistor?

simulate this circuit – Schematic created using CircuitLab I've solved for all of the currents in the circuit (I used an equivalent resistance for the middle two resistors) and the ...
1
vote
2answers
84 views

How do I calculate voltage using the complete diode method?

Doing extra examples for a electronics class, came across a section uses the Complete Diode Model (We haven't covered it in class in much detail, only the definition). The question is: Determine the ...
3
votes
2answers
235 views

What happens if I put my DC voltage source AFTER the diode instead of before?

I have a homework question on diodes, in which I have to calculate the Voltages across the diodes. All the questions I have encountered thus far have had the DC source BEFORE the diode. This one has ...
0
votes
1answer
88 views

ADC for low signal (microvolts)

I am a newbie to electronics I have a sensor that can provide a range of [400 microvolts - 5 Volts] I want to transform this signal into Digital so that i can read it on computer, I'm seeking a ...
1
vote
1answer
66 views

How can I calibrate my sound card based oscilloscope?

I'm using Soundcard Oscilloscope software that presents as below You'll notice that the display has a grid, and in the example is set for 100mV/div. Since it's using the sound card integral to my ...
0
votes
1answer
54 views

For sensing continuous Voltage and deamplifier circuit? [closed]

Basically, OpAmp is used for the purpose of the amplifying the voltage in the circuit and in the circuit below, i supplied 10v and it is deamplified to 1A. The ratio of attenuation is 0.1. The circuit ...
1
vote
0answers
56 views

Measuring battery voltage fluctuations and spikes in an analog wall mounted clock when the second hand ticks

As the title suggests, my goal is to be able to pickup minute voltage fluctuations of an AA battery cell of the wall-mounted clock, each time the second hand ticks. My first intuition would be to ...
3
votes
1answer
77 views

Is it practical to measure an unknown capacitance by measuring its impedance?

I've recently seen some fourth year engineering projects at my school (University of Waterloo) and one that I found interesting was this novel pressure sensor that uses nano silver separated by a ...
2
votes
1answer
44 views

Ungenerated Voltage across the DMM and random spikes across the Oscilloscope

I am working with piezoelectric material known as PZT-P-43 MY PZT datasheet (please look at the red outlined). So far I have been trying to find the Energy that is being delivered to my 100uF ...
0
votes
1answer
63 views

Non-rectified Voltage output across the capacitor

So I am testing my PZT Piezoelectric material's Voltage output across a Capacitor of 1000uF after converting AC to DC using an Oscilloscope. Oscilloscope model: Gwinstek GDS-2102. The diagram is my ...
1
vote
1answer
53 views

KVL not satisfied during simple diode series

A power diode in the reverse biased position is connected in series to a 2.5Mohm resistor. The voltage source is connected in series to these two components and is set at 10V dc. The voltage across ...
2
votes
1answer
101 views

Piezoelectric Voltage and current measurement across a 3.3kohm resistor.

I am testing a PZT 43 material with tapping sequence. The measurement of the material is: 10mm in length and 0.8CM in diameter. I am tapping the material with a plastic and holding it down with a ...
0
votes
0answers
47 views

Efficiently sense volage DC/AC?

In our current design we are sensing 50 Vdc input voltage through a microcontroller by using resistor divider network, caps for filtering high frequency noises,diodes for protection. The problem here ...
1
vote
2answers
276 views

Voltmeter measuring electromotive force of a battery

It is known that connecting a voltmeter directly to the terminals(without any other load) of a battery will show you the value of the battery's EMF.However,I don't really undrerstand how this ...
0
votes
2answers
42 views

Voltage level when connectiong two power sources [closed]

I've experienced the following situation the other day. When connected to this smart powers charger (never seen one of those), the battery voltage dropped. Made me wonder about two questions. 1. ...
28
votes
10answers
5k views

Multimeter exploded during ACV measurment - What did I do wrong?

simulate this circuit – Schematic created using CircuitLab A DT-830B meter. I bought a new transformer, and I was trying to measure the output voltage. I plugged the probes on 'VΩmA' ...
2
votes
1answer
72 views

Differential measurements with high voltage oscilloscope probes

This interesting post about differential measurements with a scope has raised a few questions in my mind. I have read about true differential scope probes and they seem to be very expensive. Would ...
0
votes
1answer
95 views

How to measure a BC-547 transistor's details?

I am new in electronics. What I am trying to do is measuring everything of BC-547 transistor's details from a basic circuit design practically. I want to measure as example: collector-emitter ...
0
votes
2answers
103 views

How does vacuum tube heating (heater voltage) affect tube performance/sound?

I have replaced a 12AX7 tube with ECC85 in my guitar amp. Seems to work great and sound great. The part that is questioning me is whether the sound is being at its best because it takes a good 20-30 ...
0
votes
1answer
51 views

Battery voltage isolated monitoring on Microcontroller

Is it safe to directly measure high capacity battery (100 Ah to 300 Ah) voltage with Microcontroller's Analog to Digital Converter (ADC)? Would it be enough to use just a simple voltage divider to do ...
0
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3answers
156 views

Battery voltage select and ADC measurement (OpAmp + uC)

I need to measure battery voltage which supplies my electronics. Vbat supplies buck-boost DC/DC converter then goes to uC and other ICs (3,3V). I want to use 3x2 goldpins in conjunction with OpAmp to ...
0
votes
2answers
104 views

Can I measure if current is on or off in cable with 24v DC (in a cheap way)

I have a number of valves that control the heating in rooms in our house. The valves have a pin on top which opens or closes the valve. The position of the pin is controlled by a regulator that sits ...
0
votes
2answers
50 views

what is the base temperature when using ppm/c

I am not sure If I have phrased the question right but if not please correct me I want to know when Accuracy Parts per Million mentioned in the datasheet of voltage reference they say for example 5 ...
1
vote
1answer
57 views

VGA levels, why are they wrong?

I read everywhere on the Internet that voltage levels in the color components of a VGA cable should go from 0 V (dark channel) to 0.7 V (maximum brightness for that channel). However I tried to ...
2
votes
3answers
118 views

Correct way to measure a wall wart voltage [duplicate]

I got a full drawer of second hand wall warts which I'm planning to use for powering arduino projects (mostly 5V "pro mini" or "nano"). I'm using a voltmeter to check that they are still working, ...
3
votes
5answers
229 views

Is voltage measurement of a battery done in series?

This might be a stupid question but I can't find an explanation. Voltage measurement is done in parallel. But when we measure the voltage of a stand alone voltage source, say a battery, it looks like ...
4
votes
3answers
89 views

Measurement of negative DC voltage

I want to measure -30Vdc up to 0Vdc using a microcontroller. I'm basically measuring a voltage source with an output current of upto 2A. I need to bring the voltage up onto a scale of 0V to 5V so ...
0
votes
1answer
60 views

Measure Voltage (Divide) on a current source

I need to use a constant current source 20mA, the current flows through multiple diodes and resistors which are in series. The resistor value can vary from 0 to 1.6k and also a possibility of Open. ...
0
votes
1answer
182 views

A DC micro-voltmeter

Basically I will be calibrating circuits to a high degree of precision. Keeping it minimalistic, I figure all I needed for that are resistor networks, voltmeters and a few high precision voltage ...
0
votes
1answer
166 views

continuous battery monitoring during charging as well as discharging

My application is basically a power monitoring system in which inverter voltage(RMS),current(RMS) and battery voltage,current are measured. 24V battery is being used in the application. I am using ...
0
votes
1answer
102 views

Measure resistance value between all nodes in a 3x3 resistor grid

I have a Schematic like that: (except the power supply is an Arduino Uno with a voltage divider to measure resistance between any pair of ABC and 123, except C3 of course) How can I get the ...
1
vote
2answers
44 views

Type of Wideband Transformer for Measuring 120 V AC signal + EMI

I'm looking to measure line EMI on a standard 120 V AC power circuit using some kind of transformer or other sensor. The device I'll be using to measure the waveform is an Ettus Research USRP N210, ...
2
votes
1answer
122 views

How can one use the earth as a second wire?

I read recently that the earth can be used as a wire to save wiring costs. My understanding of how this works is that a power source, say a battery, separates charge, creating electrons on one side ...
-1
votes
2answers
248 views

What's the most economical way to digitally measure 240V mains voltage, current and power factor?

I'm looking to capture and analyse measurements of the mains energy that I use per circuit. I've found a few consumer products that offer powerpoint energy monitoring such as the Kill-A-Watt, but PC ...
1
vote
1answer
50 views

Old 9v battery - Strange Behavior

The battery in my garage door remote finally quit. Before replacing it, I measured the voltage with a digital multimeter and was surprised to find it reading 9.70v, quite a bit higher than the ...
1
vote
1answer
225 views

Measuring Battery Voltage from Microcontroller using ADC

I am currently using a PIC16f1826 to try and measure the voltage of the 3.7v battery that is powering said microcontroller. From my understanding, the ADC can measure from 0v up to the reference ...
1
vote
1answer
84 views

Measuring the amplitude of a sine wave

I want to measure the amplitude of a sine current signal (about 1kHz). The signal is of small amplitude, i.e. smaller than 50 mA. I suppose a simple rectifier is not accurate enough or even doesn't. ...
2
votes
2answers
104 views

Accurate RF voltage magnitude measurement

How would you measure the magnitude of a RF sinewave in the KV, MHz ballpark? The frequency is known and the sinewave is very pure, does this help? Can you devise a method that would give ...
0
votes
2answers
125 views

Why does DMM resistance measurement not settle when probing pins on circuit?

I am probing two pins on a custom circuit board which I believe have been shorted somewhere and am attempting to measure the resistance between these pins with an Agilent 34401A multimeter. When ...
4
votes
2answers
143 views

When to read Battery voltage and battery current during charging

I am using a micro-controller to drive a buck converter for Li-ion battery charging purpose(Micro-controller providing PWM to the buck converter). During charging the battery's current and voltage ...
1
vote
2answers
166 views

How do security alarm systems measure zone resistance?

Recent security alarm systems use EOL(R) or DEOL(R) to terminate the line of the zones. Question 1: What method is used to measure the resistance of a zone? I can think of two options: It measures ...
1
vote
1answer
50 views

High voltage to low voltage conversion from multiple channels

There are more than 200 lines and every line carries voltages in the range of 0-36V.What are all the possible ways to convert 0-36V (pwm signal,5kHz) to 0-5V for ADC input? Note: I should not ...
2
votes
1answer
109 views

Non-contact mains voltage measurement

I am trying to develop a non-contact whole-house power usage monitor. I have reviewed jasonT's project, which uses AC clamps to measure current usage. However, from reading this post on how meters ...