Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

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).

1
vote
3answers
54 views

Capacitor max safe operating voltage

I'm currently making a power supply with a 32 volt AC out, so the rectified voltage would be 32*1.414-diode drop. The value comes around 44 volts. My question is, is it okay to hook up a 50 V rated ...
0
votes
2answers
52 views

Converting 12v to smooth 5v?

I’m working on a motorcycle here. I have a 12v battery to work with and a stator that produces (limited) power. I have a throttle position sensor that I believe needs 5v input and outputs up to 5v. ...
0
votes
0answers
22 views

Voltage Regulator with Reverse Voltage

I have designed a simple PCB circuit board that is powered by either the 5V from a USB, or if a battery is plugged in, powered from a 3.3V and 5V regulator. I am no expert in electronics, but have ...
0
votes
0answers
18 views

Hard wired exterior lights powered by battery pack

I would like to connect a string of decorative exterior Christmas lights powered by 3 AA batteries directly to my landscape lighting system (~12 volts). How can this be accomplished? Thanks!
0
votes
1answer
43 views

Laptop chargers that say 20V, are they for charging 5s?

I understand that 5s Li-ion should be charged at 21V (4.2*5) however the only laptop chargers I can find are 19V, 20V, and 24V. Each is relatively close to the value that should be used for 4s, 5s and ...
0
votes
0answers
37 views

How to Find Resistor for Maximum Power Transfer?

I honestly have no idea what is the best way to find RL for maximum power transfer in this circuit. What I do know, first and foremost, is that the RL resistor can be found as the Thevenin-...
0
votes
1answer
38 views

Use a European halogen electric light fixture in the U.S.

I brought a halogen standing light fixture home to the U.S. from Europe. The light worked using an adapter to convert the Euro plug to the U.S. plug, but the light was dim. I read that the wattage ...
-4
votes
0answers
69 views

Intended use of 30V 5A bench power supplies? [on hold]

I'm only curious. The market seems to be dominated by 30V 5A supplies. Who/what is the intended target? LED lights, stepper motors, something else? Most of my experiments with micro controllers and ...
1
vote
0answers
42 views

Finding Current in Parallel RLC Circuit with 2 voltage sources?

I've spent sometime learning about step responses for series/parallel RLC circuits, but this problem takes things a step further, since C seems to be in parallel with a series combination of RL and a ...
1
vote
1answer
55 views

Please check my DC / DC schematic. ST1S40

I want to make a voltage down converter to power my controller (Atmega328P). Input = 12V / Output = 5V (3A). As a converter, I use ST1S40. My connection diagram I took the circuit from datasheet, ...
0
votes
1answer
62 views

What's the magic behind inverters?

I'm having hard time understanding how inverter works and why it works. I mean why is it possible to power a say fridge (220V AC) with a 5v battery using a 5v to 220v inverter ? And since this is ...
0
votes
1answer
45 views

Sticking to high voltage DC Current

I heard that if you come into contact with a high voltage DC current, you will ‘stick’ to it until it is switched off. Why is this and how high does the voltage have to be for someone to ‘stick’ to it?...
14
votes
9answers
3k views

Does battery voltage actually get lower when connected to a load, or does it just appear to do so?

Sorry if Im wording this question strangely. I am using a 3.7V battery and my microcontroller monitors the voltage and goes to sleep if my battery voltage is too low. The issue is that it reads a ...
-5
votes
1answer
65 views

What happens if i connect same potential to the two side of wire?

In my opinion nothing should happens but correct me if I'm wrong. The reason for asking this foolish question is that I was searching about short circuit and then I came to know that if two wires of ...
0
votes
0answers
30 views

abc dq transform for inverter inner and outer control

Good day all, I am learning inverters (VSC) and their control of inner and outer loop which are current and DC bus voltage control respectively. I understood the current control and it seemed to me ...
0
votes
0answers
34 views

To use a LM392 do Operational Amplifier and Voltage Comparative [on hold]

The LM392 consists of two independent building-block circuits. One is a high-gain internally-frequency-compensated operational amplifier, and the other is a precision voltage comparator. May I use ...
1
vote
1answer
44 views

Understanding some mistakes, when trying to find the Thevenin equivalent

I was asked to find the Thevenin-Norton equivelant, and I got stuck on some things that I can't quite understand. I don't know if i need to be more specific. What's wrong with the following? And why ...
1
vote
1answer
46 views

Does voltage drop with discharge?

Does voltage drop with discharge? Since voltage is the potentiality between two charges to re-balance (from my understanding). I mean, once all charges are equally shared between both capacitor ...
0
votes
2answers
97 views

Clarification on This Transformer Statement

Secondly, when the current starts to rise in the secondary wire, the magnetic field it generates is multiplied by the loop count. Obviously if we had lots of loops, a very small current will ...
0
votes
2answers
63 views

Garage door impulse generator volt free

I have a NovoPort (PDF) garage door opener and I want to control the door with an ESP32. One of the issues I am having is the warning for "Do not connect any current-carrying cables". In the photo ...
-1
votes
0answers
28 views

DC-AC circuits exercises

I have some problems with electronics and I can't solve the two exercises below: the first one: and the second one: In the second exercise I managed to calculate (hopefully it is correct) that DC ...
1
vote
2answers
85 views

How current and potential propagate through electrical circuits?

I have something of a theoretical question. In any given electrical/electronic circuit there seems to be an electric field developed inside (and outside the conductors?) to push the electrons in the ...
0
votes
7answers
135 views

Calculating the voltage drop of two Zener diodes in series? (reverse conducting)

I'm building a circuit powered from a 12V 55mAh (A23 battery). Needless to say that power consumption is a primary concern. The circuit is an ATtiny85 which is driving 13 LED's (in 5 groups). I ...
1
vote
1answer
35 views

Voltage Measurement with ST Microcontroller

I want to measure DC voltages from 1mV to 10V. I will be using STM32L053C8T6 Discovery board. I want to use 3.3V reference voltage. I know that if you want to measure voltages bigger than reference ...
0
votes
1answer
29 views

Synchronous Generator EMI

In the attached image below, I don't understand the text and phasor diagram that I have highlighted in yellow. Why does the induced emf on the armature winding lag the magnetic flux of the ...
0
votes
1answer
51 views

Is the “Volt” a measure of force or energy consumption?

A little confusion on my part. I see that a volt is the SI unit of electromotive force as the Wikipedia may show. I also see that One Volt is defined as energy consumption of one joule per ...
0
votes
0answers
19 views

AC sweep/noise simulation error

I have designed a simple audio amplifier circuit. When I ran the simulation with Time Domain Transient, it was able to produce a nice sine wave with about 20x amplification using the Vsin voltage ...
1
vote
0answers
33 views

How do you calculate average absolute value of a sum of sin functions with different amplitudes and frequencies?

I cant seem to find the answer anywhere. I remember there was a simple formula for doing this but I dont have the book with it anymore. Finding where the function is positive and where is negative and ...
1
vote
2answers
43 views

How does an op amp compare voltage?

How does an op-amp know where the ground is because the inputs are single wires, how does an op-amp compare them to a ground like this circuit for example clearly the op-amp is not connected to ...
0
votes
2answers
32 views

Lower wattage of IR bulbs permanently

I have two 90w/12v infrared IR bulbs which is put into a r7s sockets. From thes socket goes in total four wires which is connected to our power supply. We have set two of the wires in serial so they ...
0
votes
1answer
23 views

Whats the difference between a battery charger & Transformer to power a 12 V 3 A bilge pump?

I made a common mistake, identical to an earlier post "Using a 12 V 3 A bilge pump on a 12 V 8.5 A LED power supply". The pump was 3.8 amp so I purchased a 5amp led transformer, which just worked, ...
0
votes
2answers
25 views

In powering household devices, is the voltage preset and the amperage varies as needed?

When powering household devices, does a power adapter have a preset (or in some cases user-defined) voltage, while the device (while turned on) "selects"/draws whatever amount of amperage it needs at ...
0
votes
1answer
17 views

(pyramid xpa-240)if i had 10 voltage extra to a amplifiers what will happen? [closed]

I have a pyramid xpa-240 amplifier that does work with 110/220 voltage i want to know if it ok to use on 240 voltage? Or is the voltage to much for the amplifier?
0
votes
2answers
28 views

5V output on AAA Ni-Mh battery charger?

I bought a cheap Ni-Mh battery charger from Aliexpress to charge my rechargeable AA and AAA 1.2V batteries but before I plug them in, I checked the voltage on the charger terminals and it is reading ...
1
vote
1answer
66 views

Calculating a voltmeter reading

I'd like to preface with saying that I'm quite new to this. Given emf E = 9 V, and that both resistances are equal, R = 1 kΩ, ...
0
votes
1answer
62 views

Battery voltage drops to 0

I have this type of battery. When it was fully charged I read with the multimeter aroud 38-39 volts. Now I read 21 volts. The question is: When I connect the battery (discharged - 21,22 v) to a bldc ...
0
votes
1answer
46 views

How does distance between parallel batteries affect voltage drop/required wire thickness?

I'm looking to wire up an off-grid system. What I'm stuck on is battery placement. The likelihood is my batteries will need to be quite far apart (almost 2 metres). My question is how does this ...
-8
votes
0answers
22 views

Determine the voltage across resistor by using superposition [closed]

Determine the voltage across resistor by using superposition.
1
vote
1answer
36 views

Determining Battery Charging and Discharging Rate Based on Max Current and Nominal Voltage

I am having difficulty in figuring out some basic stuff and confused with multiple equations. I am working on a simulator which simulate a hybrid vehicle journey for some period of time. During ...
0
votes
0answers
57 views

Missing resistors vaules

A question for some guys is simple, but it is not for me. I am having difficulties finding the right formula to calculate resistors value or voltage drop across R1 through R8. Does anyone have an ...
0
votes
1answer
53 views

How to solve this circuit using KCL

I understand the super node aspect of this circuit, but I'm unsure of what to do as I dont see a direct way to proceed with KCL using all of the nodes. I found the equation for the supernode, but I'm ...
0
votes
0answers
30 views

Parallel DC sources with varying voltages

I have different DC sources which i want to hook up to a 24v battery pack. - Solar controller output - AC/DC charger - truck alternator Can i connect these in parallel? I've been told that because ...
-1
votes
1answer
27 views

Series voltage and voltage tester module

I have a question about battery tester module. I have in my hands a board that shows the capacity of a 3.7V 18650 LiPo, presumably by measuring voltage. It has 4 LEDs on it. If I hook this up to ...
0
votes
2answers
60 views

Voltage control

I've been trying to design a control circuit to switch supply. What I want to achieve? I need 24V voltage for supplying an ultrasound sensor. There are two ways of gaining 24V: ...
0
votes
0answers
32 views

temperature and humidity controller power supply (ZFX-ST3022)

I am new to electrical engineering, but recently I have decided to make an effort and learn the basics with a small project consisting of making an isolated chamber with constant temperature and ...
0
votes
2answers
77 views

AC voltage on the outside surface of micro USB charger cable

My micro USB mobile charge cable is having about 98V AC voltage on the outside surface. (PFA measurement image. The black probe is connected to the Power socket Ground port. I could not take the whole ...
0
votes
1answer
51 views

Series circuit LED controlled by Arduino schematic question

I'm currently making a project with multiple series circuits to PWM control multiple LEDs. I have figured out how to make it work with a transistor, however I was curious if this way would work as ...
0
votes
2answers
51 views

About the voltage usage in house [closed]

Don't take this the wrong way I am new to electrical stuff, so please help me in understanding my confusion. I have an extension cord with 4 sockets and it's plugged into the house mains 240V at 50/60 ...
1
vote
2answers
66 views

Is my understanding of current, voltage, and resistance correct?

Im currently a senior in highschool. So I know that voltage is the potential difference per unit charge, or from my understanding the work done to move a unit charge from point a to point b without ...
0
votes
2answers
104 views

How can fully charge a capacitor without having it prematurely discharge?

I am looking to power a circuit using a 5.5V, 5F supercapacitor. I want to charge it to approx. 5V but I don't want it to discharge into my circuit until it has charged to 5V. I can do this by simply ...