# Questions tagged [voltage]

Voltage, otherwise known as electrical potential difference (denoted ∆V and measured in volts) is the difference in electric potential between two points (adapted from Wikipedia). Voltage can be constant (DC) or varying (AC).

5,364 questions
Filter by
Sorted by
Tagged with
21 views

### why is the the Line voltage drop formula is $\Delta V=2I_1 (Rcos\theta+Xsin\theta)$,not $\Delta V=2I_1(\sqrt{R^2+X^2})$?

There is a single-phase two-wire system,if the resistor $(R)$ of line is 1Ω and the reactance $(X)$ of line is 2Ω,and the power factor is $\theta$ .The Line voltage drop formula should be \...
14 views

### Circuit Analysis with constant couurent and voltage sources

This is a homework question of sorts. You are supposed to find voltage across AB. PS: new to StackExchange
11 views

### Relationship between power angle and real and apparent in ECO dataset

I am trying to parse the ECO dataset, which includes 1-second electric data collected from residential houses. Link to dataset: http://vs.inf.ethz.ch/res/show.html?what=eco-data But the relationship ...
51 views

### What is the voltage value measured by an 8-bit ADC chip showing a binary reading of 64? the reference voltage is 3.3V

I followed the explanation in this post. I did 3.3 V/256 = ‭‭0.01289 V . I also did 3.3 V/(256/1.5) = ‭0.01964 . And lastly, I used this formula: I just keep getting the wrong answer! Please could ...
35 views

### Read triangular wave with positive and negative part to Arduino

I generate a triangular wave with a 555, and I want the Arduino to read this signal. What should I do to read negative part?
18 views

### WS2812b interference and bootup behavior

TL;DR: how can a slowly rising power supply voltage on an arduino crash the WS2812bs connected to it? How can I protect a signal wire even better from electrical interference? This my question in a ...
65 views

### 6.2 V zener shows lower voltage (Multisim)

I have this circuit with a 1N4735A 6.2 V zener diode. I am trying to figure out why am I measuring 5.1 V across it. The circuit is a transformerless power supply with more or less 60 mA of maximum ...
55 views

### Why can we use less voltage drop to transmit the power if the higher voltage is used?

In power distribution systems, a given amount of power can be transmitted with less voltage drop if a higher voltage is used. However,i don't understand the reason about this In my thinking,if i ...
42 views

### USB-C PD, Voltage and Current of Power Adaptors [closed]

I have a rather basic question... but I don't want to take chances. I have two MacBook Pros, one which ships with a 87W power unit, and the other a 96W power unit. Now, I understand that a device ...
35 views

### Can I use a plug rated for a DC circuit in a low voltage AC circuit?

I have an spare 2-conductor plug rated for 12VDC at 5A from an old project. I’m now working on a Class II low voltage (24VAC) projet for which I need just such a plug. Is the plug rated for the DC ...
71 views

### What could happen if I touch a constant current source for example 5 Volts 1 Amp..?

Yes, I am talking about a constant current source not a voltage source. Would the 1 Amp go to my body?
102 views

### Is it safe to touch 8 volts?

Let me say first that i'm a noob in electricity. I measured the voltage from my diy microwave-transformer-welder and it was 8. I have no idea how much amps run through it but the fact that it creates ...
40 views

### Is input noise in a dual OpAmp device common to both channels?

I'm designing an input buffer stage for a low voltage, noise sensitive application. These buffer stages consist of dual package OpAmps, with each individual OpAmp buffering the + or - input to a ...
105 views

### How does a center tapped transformer work?

I'm having trouble understanding the electric principles that allow a center tapped transformer to work. Lets say we're working with 240/120V. I understand if you connect a voltmeter across the top ...
42 views

### Questions regarding AFG3000C function generator

I have a new function generator - model AFG3000C. I am having difficulty in understanding certain terms related to this function generator. I have tried online searches, but I couldn't get what I ...
54 views

### Constant current density

I am reading an article that says ... constant current density of $−1.0\,\mathrm{A \cdot cm^{-2}}$ Let's say that I have material that's $2\,\mathrm{cm^{2}}$, how would I calculate what's the ...
28 views

### Open Circuit Voltage with Open FET and Zener?

D2 is a 18V Zener, LM3Z18VT1, diode. M1 is a NCE01P30K. Node DO is 8V by default and 0V when the circuit activates. If M2 in the circuit below opens, what is the voltage at the gate of M1? Now ...
45 views

### How do I drive a 5W low pressure mercury UVC bulb?

How do I determine the voltage and necessary power supply for this bulb. This bulb is a UVC low pressure mercury vapor bulb used in my air purifier. It fits in a G23 Socket, normally I would expect a ...
57 views

### Function Generator Voltage and Current handling

I am using this Function Generator My circuit : FG input : 5V peak to peak. 1kHz. 1ms time period. 90% duty. I want to understand the below questions : Is it safe to do this connection? I have ...
48 views

### with a L298N controller I need to “warm up” the motor to get it to run without stopping, why and how to do it with python

I understand that this will be a very trivial question but I cannot find an explanation online, probably because in my ignorance I'm asking the wrong question, to support my explanation I'm leaving ...
105 views

### Signal voltage scaling

I have a linear range control signal from 1.75 V (0%) to 3.22 V (100%) . How can I convert this to a 0-5V signal (0-100%)? I have a single +5V supply with same 0V as control signal.
60 views

### What does it mean for a power supply to have an output range?

I had a power supply blow and I replaced it with one from the same company with the same model number. The new supply has lightly different specification than the old supply. Oddly (to me) it gives ...
24 views

### Arduino w 5V Relay Wiring

I am having trouble actuating this relay I bought off Amazon. I have been successful actuating the relay but am having issues wiring up a LED to simply turn on and off. My setup looks very similar to ...
107 views

### I fried my Raspberry Pi while using L298N but I don't understand why

Everything seems to indicate that I fried my raspberry pi: the green light wouldn't turn on, I changed the SD card for a new one but it still didn't work. That is a shame because I was having a lot ...
60 views

### How does this RPM sensor work? – Induction in an open circut

I'm looking for explanation of some basic induction concepts. It's common to see an RPM sensor for small two and four stroke engines where an open-ended wire is coiled around the spark plug's ...
96 views

### My apartment's mains voltage rises from 220 V at noon to 245 V at night

I'm Egyptian, and the standard mains voltage in Egypt is between 220 V to 240 V. The mains voltage in my apartment keeps rising daily from 220 V at noon to 245 V at night. Should I worry, and what ...
94 views

### What is maximum and minimum current through zener diode?

For a simple electronic voltage regulator using Zener diode, I use the following circuit. For deciding Rs and RL, I need to know Izmax and Izmin of the zener diode 1N4736A used. From this data sheet, ...
56 views

### Using Thévenin's Theorem / Voltage Across Independent Current Sources

I've been attempting this problem regarding the usage of Thévenin's Theorem to find the value of Io. I am able to get the correct Thevenin Resistance, however attempting to find the Thevenin Voltage ...
22 views

### Gamecube controller hack with raspberry pi

Electrical noob here. I am trying to control a gamecube controller from a raspberry pi. Meaning: I want to have wires from the pi soldered onto the board of the gamecube contoller and emulate button ...
40 views

61 views

### How to convert a PWM signal to analog

I am trying to drive a 3 pin fan using my MCU. The 3 pins of the fan are 1- Gnd, 2- Vdd, 3- Open drain RPM output The fan can draw up to 0.5 Amp. My initial idea was to use a Darlington transistor,...
66 views

### peltier not cooling anything

Hello I am trying to use 30 "tec-1 12706" peltiers along with my geothermal ground loop to cool machines. I have (2) banks of 15 in series and the two bank parallel to each other electrically. Power ...
12 views

### Power Supply Req: Need 20A 240V [migrated]

Sorry for the basic question, I am not especially electrically minded. I have a system that requires 16A and 240V power, however we only have 10A wall outlet power available. I did consider ...