Energy is defined as the amount of work that can be performed by force, measured in Joules. Energy is Power over Time. This is a poor tag to use. Please consider if your question relates to Energy as defined in physics, not as a synonym for Power or capacity.

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Fetching Electrical Parameters through a Meter (ELMEASURE TM5410 to PC) [on hold]

I'm having an El-Measure TM5410 and I want to fetch the readings of this meter onto my computer. I am using a SAN TELEQUIP SC11 USB to RS485/RS422 converter to connect the computer with this meter. ...
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2answers
64 views

Energy direction in an electronic circuit

I've been reading a number of materials trying to understand the physics that allow electricity to be possible. I'm confused by this virtual positive [charged] particle (often called a test particle) ...
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2answers
54 views

Solar panel calculation

I have a small solar panel of the following, Area = 0.0078 square meter Rated Power = 1 W Now, I am interested to calculated the total energy this solar panel can harvest over a day. I am taking ...
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1answer
42 views

How to monitor produced energy?

I want to monitor energy produced by 250W solar panel. But I need some hints. Does anyone knows something? Is it possible using ACS758 chip or better I have to use current transformator? Finally I ...
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1answer
146 views

Theory behind the “Joule Ringer” circuit

The less-than-critical thinking free energy types are pointing to the "Super Joule Ringer" demonstrations online, where a quick touch with a 9 V battery illuminates an LED for hours. ...
2
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0answers
79 views

Charging capacitors in parallel with a battery

I am trying to figure out a system to charge a series capacitor bank without too much current going through the capacitors. I had the idea of putting a battery in parallel with the series capacitor ...
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0answers
49 views

Can't find Broadcom BCM4329 datasheet

I need to find information about my phone energy consumption and I can't find a proper datasheet about the BCM4329 chipset. Does someone have it? I'd like to create a power profile for PowerTutor in ...
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2answers
106 views

How to understand the “basics” of electricity? [closed]

I want to be a self-taught computer engineer ... massive goal, but it's what I want eventually. I check out textbooks and online resources, but I feel like I need a prerequisite somewhat -- I still ...
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4answers
76 views

Calculation of PV daily energy yield

How can you calculate how much energy a PV panel (known size and wattage) produces in a day given the exact insolation in kWh/m2/day?
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1answer
61 views

Can I connect my Philips sound system to my Samsung tablet? [closed]

I have a Philips SPA 4310/10 Sound System and I want to connect via 3.5mm jack to my 10" Samsung Galaxy Tab 3 P5200 to listen some music. Am I at risk of short-circuiting the tablet? Or will ...
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3answers
100 views

Why harvesting energy why not harvesting power?

I am wondering why is it called Harvesting energy and why not harvesting power? Energy is measured in Joules/s and power is Watt but the result is watt. For example if we harvest energy from sun or ...
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2answers
74 views

Tippmatic auto shut-off switch - how to use it?

Some products in my company are now required to use an auto shut-off switch to be compliant with new regulations in European space (European Eco-Design Directive ErP). I got word that the device ...
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2answers
82 views

A good way to storage/precharge energy for short bursts of consumption?

I have a battery powered application that must occasionally use a servo motor (like the ones in model airplanes, e.g. Turnigy TR-1160A). This servo will be used in short bursts of 1~2 seconds at a ...
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2answers
65 views

Four quadrant description

I am developing applications for energy automation for power generation and distribution utilities but i dont have much electrical engineering background. I always have confusion when it comes to ...
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1answer
50 views

The bandwidth Ω of a low-pass signal f(t) ↔ F(ω)

I'm not sure about the answers to the two parts of this question: The bandwidth Ω of a low-pass signal f(t) ↔ F(ω) is defined by the constraint: $$ \frac{1}{2\pi } \int_{- \Omega }^{\Omega } ...
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1answer
71 views

How does the principle of conservation of energy for a phase-shifter transformer apply?

Since the phase shifter transformer is used for regulating the real power in the transmission line by means of changing the angle it leads to the fact that the real power at the secondary side ...
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0answers
38 views

What happens to the energy bands when a forward bias > Buit-in potential is applied [duplicate]

When we applied a forward bias across a PN junction, the barrier height of the depletion region reduces. What will happen to the energy bands when we apply the forward bias greater that the built-in ...
2
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1answer
59 views

Dynamic energy and dynamic power in microprocessors

In a class I'm learning about dynamic energy and dynamic power and the notes seem to be incomplete. ...
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1answer
82 views

Charging of Cell Phone Batteries and Electricity! [closed]

Does charging an already charged battery of cell phones/laptops consume electricity? Whenever my cell phone becomes fully charged while charging, it asks me to remove the charger from the socket to ...
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2answers
44 views

Energy meter design/mcp390x

I am considering the mcp390Xa series for a energy meter project. What I am not understanding here is where the voltage part of the watt calculation is happening. Is this up to the micro to measure ...
2
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1answer
129 views

Extracting the Most Energy From a Capacitor

I have a 5V super capacitor which I'm trying to extract the most energy from in the most efficient way possible. This capacitor is tied to the input of some regulator (which is the question of this ...
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0answers
53 views

Measuring consumed energy with MCP3905A

first of all sorry for my English because I'm Italian. I'm trying to measure consumed energy with MCP3905A evaluation borad. ...
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2answers
96 views

Ohm's Law vs. Conservation of Energy Misunderstanding

I am currently misunderstanding the relation between Ohm's Law and the law for conservation of energy. I am referring to the example (in the book "Foundations of Analog and Digital Electronic ...
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3answers
374 views

How long can I practically power an IC with a capacitor?

If I have, for example, an IC that draws 10mA @ 3.3V, how large of a capacitor would I need to power it for 2 minutes? 5 minutes? I understand that using capacitors to power an IC is not the most ...
2
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6answers
426 views

Difference between Voltage source and Current source?

So what's the difference between a Voltage source and a Current source? Aren't they the same? Because after all they are related with the formula \$V = IR\$. So it means that If we produce a voltage, ...
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2answers
195 views

Connecting two capacitors in parallel

Two capacitors are parallel connected with an open switch. Both have a different capacity in which: $$c_1>c_2$$ and both charged with a different voltage $$v_1\neq v_2$$ and now we close the ...
5
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4answers
272 views

Do real and reactive energy exist?

Are there any such things as real and reactive energies just like real and reactive power? if so, how is reactive energy dissipated?
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3answers
59 views

Energy of a signal [closed]

In signal analysis we work out the energy of a signal. We get a number and thats the end of the story, but theres no explanation of what it means in practise. If it was just some abstract mathematical ...
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2answers
215 views

3-phase energy meter with CTs

I need to measure 3-phases. Usually I would use CTs on the differential port on a LTC1966, then connect Vout+ to an ADC port on a uC. I do that on a 1-phase application. The problem is now, that we ...
3
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1answer
612 views

Logging measurements from an analog Gas Meter

I want to capture a gasmeter counter to log the gas consumption in my database. Problem: till now I did not find a way to read the meter. I tried a sensitive hall sensor that could react on the ...
2
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2answers
608 views

Arduino: How can one control a 2-wire DC motor with PWM?

I want to control the speed of a two-wire DC motor using PWM. I already managed to control a 4-wire motor, but now I need to use a two-wire motor. I would connect it to the Arduino directly, but the ...
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votes
2answers
96 views

How long should I leave the light on? [closed]

I'm not sure if this qualifies as electrical engineering, but I remember my old physics teacher at school saying that if you switch a light on in a room and you're planning to return relatively ...
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3answers
137 views

Is the energy flow due to a an alternating current constant or cyclic

I understand that the Poynting vector shows us that energy flows in the region outside, or between, conductors, but the maths gets too deep for me to discover, when the current is alternating, whether ...
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0answers
228 views

Calculating true power/energy usage from battery on smartphone?

I am having some problem to calculate power consumption from android smartphone... First my setup: Android smartphone is connected to PC with USB. Both smartphone and USB do not provide their own ...
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0answers
91 views

When a smartphone is connected to a charger (USB), does it use battery or charger as it's main power supply? [closed]

When a smartphone (fully charged) is connected via USB to PC (or to charger) does it uses charger or it's own battery as main power supply? Battery is supplying about 3.8-4.1 V and USB ~5V.
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1answer
184 views

Typical Power circuit for smartphones? Correct energy measurement? (Nexus 4, iPhone.. etc)

I am trying to perform some energy measurements using smartphone. And to make sure that I am performing my calculations correctly, I been trying to find any examples of typical power circuit in ...
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votes
2answers
325 views

Where does all the power consumed by a CPU go?

Where does all the power consumption of a CPU go? Does all the power drawn by the PC's CPU get transformed into heat? Or does it get transformed into part heat and part some other kind of energy?
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3answers
734 views

Does higher resolution of LCD/LED display mean higher energy consumption for the very same matrix size

If two mobile devices being compared have exactly the same LCD/LED screen (matrix) size and exactly the same battery, will the one with higher resolution have higher battery consumption and thus will ...
2
votes
2answers
88 views

charge extraction from solar cells in low light conditions

This is probably not that deep a question, but how can one extract power from panels in low light? A 6V panel would dip to ~2V or so, and power output would sink lower. In conventional systems, how is ...
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1answer
67 views

power source unit for two devices

I have two boards that need 2.5A each and 12V for input. I do have a cable to split the DC, like this one ...
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2answers
77 views

Kilowatt hour from Complex power

How can I calculate Kilowatt Hours from: Complex Power = 1,5 kVA Electrical current consumption = 10 A It's three-phase electric power.
2
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1answer
173 views

Finding the total energy of the network in steady state

i got a network below in steady state im trying to find the energy in the network by the capacitors and inductors. simulate this circuit – Schematic created using CircuitLab My attempt ...
18
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1answer
591 views

Does this device which claims to reduce reactive energy from a house work?

I've opened a device that states that it can reduce the reactive energy from a house, by plugin it directly to the power outlet/wall socket. I think it is a con, so I've opened it and I saw this black ...
2
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0answers
276 views

How calculate three phase kilowatt hour from time sampled data of voltage and current of each phase

My problem is I want to calculate three phase kilo watt hour from time sampled data of current and voltages. My doubts 1) How can I calculate the kilowatt hour from time sampled data? Is it any ...
4
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1answer
115 views

Kilowatt Hour Definition

This is a very simple question but something that I'm not able to wrap my head around. This Energy report states generated electricity. But what does "generated killowatthours" mean? I know that ...
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2answers
155 views

What happens to the circuit Voltage, Energy?

I was recently asked this question to calculate the voltage across a capacitor. The problem is described as follows :- Consider a capacitor "C" connected across a voltage source "V". Once the ...
17
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6answers
2k views

Why is an inductor not a good antenna?

[An antenna must have] current flowing along its length, so that the resulting fields radiate that energy into space. (Receiving antennas are just this process in reverse). [This] explains why ...
3
votes
2answers
274 views

Is the energy loss in a voltage drop equal to heat/mechanical work/light emitted?

I am wondering if the energy loss in a voltage drop over an entire circuit is equal to the energy transferred from the circuit (e.g. light/sound/mechanical energy/heat). If this is true, wouldn't ...
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1answer
122 views

Does shutting down and repowering CPU consume more energy?

I have an internetshop that has 20 CPUs. Only 50% on average are being used throughout a regular day and almost 80-100% during saturdays. I use a Server-Client to Shutdown an unused computer but ...
41
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6answers
10k views

Does turning a lighbulb on and off repeatedly use more energy than just leaving it on for hours?

Let's say I have a 60W bulb in a lamp in my bedroom. If I kept the lamp on for 2 hours straight but the next day, I switched it on and off 10 times in intervals of 5 minutes. Which scenario would use ...