Questions tagged [efficiency]
A measure of the overall effectiveness of a system. For example, in power conversion, it would be the ratio of output power to input power.
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Mean Well Power supplies have much lower efficiency and much higher leakage current than rated
I am going to have a power supply which will always be connected to AC mains and occasionally, a led strip will be connected and disconnected to the supply with a relay. I want an efficient and low &...
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What technical progress enabled high-efficiency charge pumps?
I found a lot of information on the internet, most of which told me that charge pumps are only suitable for low-power scenarios and they are not very efficient.
Charging ICs based on the charge pump ...
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Does power factor fluctuation affect my UPS?
I have noticed that my UPS is showing a power factor of 0.7 during the day and 0.55 at night. I did some online research and found that this is caused by load imbalance, and a low power factor means ...
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Buck/boost converter behaviour when MCU is sleeping
I'm building an optical wireless mouse based on nRF52833 and a 16340 cell, I need a sanity check on some considerations regarding the DC regulation.
The battery voltage goes from 4.2V when fully ...
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Gate bias voltage in class C amplifier
Question
How should the gate of the MOSFET be biased to achieve maximum efficiency (in class c amplifier), when gain is not important?
Explanation
On the one hand, in the tutorial (link) it is shown ...
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Lithium Ion Battery : Cell Array Configuration (V.batt when converting to ≤ 4[V] )
Question
I am seeking to array 6x 21700 lithium ion battery cells, leaving the option for:
1S • 6P (@ V.batt.nom = 03.7 [V], range: 02.7—04.2 [V])
2S • 3P (@ V.batt.nom = 07.4 [V], range: 05.4—08.4 [...
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Efficiency formula for passive complex circuit
I want to find a formula for the efficiency of this circuit, so \$\eta=P_{out}/P_{in}\$.
simulate this circuit – Schematic created using CircuitLab
I know that the real power is given by \$P=VI\...
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Efficiency curve of synchronous DC-DC controller with external MOSFETs
I'm designing a 48V to 12V, 300W buck converter. I am considering using the LM5148 controller and NTMFSC004N08MC switches. I'm confused about how synchronous DC-DC controllers can list efficiency ...
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When an electromagnetic relay is switched on, it shows a dip in the coil current for a millisecond but then increases again. why?
I am currently studying the effects of current on the coil of an electromagnetic relay and came across this graph:
Image source: Ramirez-Laboreo, E., Sagues, C., & Llorente, S. (2015). A new ...
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How do I find the efficiency of a transformer?
I am very new to transformers. I want to find the efficiency of transformer at an existing stage.
How do I find the practical efficiency of a transformer? What are the formulae and parameters we ...
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LED : Perceived Light Intensity Greater Than Actual Light Intensity (via Weber-Fechner Law)
Background
In this question, user @glen_geek posited (with linked references) that perceived light from an LED versus actual light from an LED is greater at lower duty cycles:
@kando For PWMing LEDs, ...
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LED : Efficiency vs Forward Current (rather than Light Intensity vs Input Current)
LED Characteristics
LED datasheets commonly provide:
\$ I_{v}\ [cd] \$ Light Intensity vs \$ I_{f}\ [A] \$ Forward Current
\$ V_{f}\ [V] \$ Forward Voltage vs \$ I_{f}\ [A] \$ Forward Current
(...
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Can addressable 5 V LED strips be powered with two differently strong power supplies?
I want to power 16 m of SK6812 RGBWW LED 5 V strips with 60 pixel/m. They are rated with 18 W/m which would make the maximum power ~300 W. I highly doubt that I will ever use the full power so, 200 W ...
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How can my crossover be improved? Efficiency is too low
I have been working on redoing the crossover for a pair of Dayton audio B652 Speakers, and have just been working on it through a breadboard for practice. I bought a bunch of cheap parts from bojack ...
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How do I know how much a kWh costs me if I have my private generator [closed]
I have a 10 kVA generator and its efficiency is approx. 90%
How can I know the cost of a kWh?
Estimate the price of diesel as $2.5 a liter.
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Efficiency of maximum power transfer
I’ve got this question regarding maximum power transfer. I’m trying to find the efficiency of the circuit by dividing power absorbed over power supplied. I think I found power absorbed (PL) by using ...
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How to calculate efficiency of an electrical circuit that can mimick neural network
Looking at the progress of the gpt models, i started thinking how they would be deployed to edge devices, and if that is the best way: currently using API calls.
I then started looking into mimicking ...
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How to calculate input current of dual polarity output voltage dc-dc converter
I am using one of the 10W dual polarity output dc-dc converter. My output specifications are +15V, 50mA and -15V, 50mA. My supply voltage is also 15V. I want to calculate input current. Can anyone ...
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How to define the rated efficiency of an induction motor
I have a bunch of pictures of motor nameplates (all 3 phase induction motors) and I've been asked to report the rated efficiency of each motor.
At the beginning I was doing:
$$\eta_\text{rated} = \...
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Working out the efficiency of my class-a audio amplifier on LTspice [closed]
I can't seem to work it out using the tutorials on YouTube, any help would be appreciated.
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How to calculate stepper motor efficiency
It is often said that stepper motors are inefficient but how inefficient are they compared to a brushed-motor. I could just build something and measure it but it would be nice to know beforehand ...
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How to calculate overall power efficiency of multi-stage BJT amp
I have a multi-stage BJT amplifier built using 2 NPNs and an initial N-channel MOSFET. The first BJT stage is a common-source amplifier with a bypass capacitor. The output stage is a emitter-follower ...
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Typical efficiency of logical circuit outputs
When looking at "logic" circuits (gates, level shifters, ...), usually intrinsic current consumption is specified, and is often quite low (compared to maximal recommended output currents of ...
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DC motor efficiency
I would like to build a Moment of Inertia machine:
A machine that rotates an object (with a DC motor) and can also record the angular velocity and use this to find the moment of inertia.
Initially I ...
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Bike power supply system
My idea is to build a electronic system for my bike to supply my phone and lights with energy. I want to use a Dynamo (6 V, 3 W) to charge a USB Powerbank. From its two USB ports I want to charge my ...
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How to improve efficiency of a "dead simple" motor driver - are more MOSFETs better or not?
This is a follow-up of that question.
The only reason I've got 8 transistors on that schematic is efficiency. I'm now trying to figure out whether switching losses are making it pointless to have so ...
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What is the best way to make my electric motorbike efficient? [closed]
I am currently doing research on making an electric dirtbike, but I am struggling with how I can make it at as efficient as possible.
I think I will use a BLDC motor of 2000 W and 60V and have a RPM ...
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Energy-delay-product vs. Joule to watt conversion formula
I am currently on my master's doing an assignment, and I am in this point in time extremely confused and I was wondering about this, quite possibly, stupid question. I am just too afraid to ask at ...
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Low-power high-range current monitoring
I'm working on a power circuit for a device that is usually battery powered.
Most of the time, the device is sleeping and sipping at power around ~5uA, which is great for battery life. In this state, ...
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Calculating W DC to W AC inverter efficiency
I have a DC to AC power inverter with the following information on the specs sticker:
Input: 12 VDC, 50 A max
AC Output: 115 VAC, 60 Hz, 400 W max (5 min) / 320 W continuous
Given that current in ...
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Which MOSFET for a 120W boost converter?
IRFP250N vs IRF3415
I'm making a boost converter which converts 12 V to 100 V maximum. The maximum input current is 15 A. Power of the converter is 120 W. I will drive the MOSFET with a TC4429.
At ...
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LTspice transformer and buck converter
I am trying to simulate an efficient circuit to take 120 V AC at 60 Hz and convert it to 5 V, 5 A. I have a transformer and rectifier circuit to get the 120 V down to about 12.6 V DC and I made a buck ...
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Step-down transformer energy efficiency [closed]
I moved from the US to the UK and I need to use a step-down transformer for my PC and monitor. It was recommended that I use three times the power that PC and monitor consume to account for power ...
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Microwave oven approximate efficiency [duplicate]
I just made popcorn in the microwave and I wonder how much energy my popcorn absorbed and how much energy was consumed by oven. It was 90g of corn and butter (kind of...) and it needed 800W for 3 ...
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Is a buck converter less efficient than 2 seperate PSUs?
I've built a CNC machine that runs from a 24V 400W PSU (Spindle & Electronics)
I just bought a laser to attach to it that requires 12V.
As I'd never run the spindle and laser at the same time, ...
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How much more efficient is 240 V than 120 V?
I've got a PHEV that currently uses a level 1 (120 V) charger, which works fine and can do a full charge overnight. It's fairly trivial to upgrade to a 240 V circuit, but I'd have to buy a level 2 ...
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I calculated the power loss of a switching regulator and it doesn't match the datasheet. Am I missing something?
I'm trying to figure out how On Semi's LM2575D2T-5G is only 77% efficient. It's the fixed 5 V output version of the component.
The datasheet gives Vin = 12 V and Iload = 1 A. Based on this, power in = ...
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Two similar voltage sources equidistant from a load in opposite direction
I have two 52 VDC voltage sources, each an equidistant of 200 m from my load. For this purpose, take it as one voltage source is coming from the east and the other from the west.
Along the 200 m path ...
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Are linear voltage regulators more efficient than switching regulators at very light loads?
I'm planning to make a battery application with a PIR sensor. The sensor consumes 70 μA and will be supplied with 4-5 V. I have two Li-ion batteries in series which gives around 8-9 V in total.
I have ...
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Efficiency when splitting output from switching AC-DC power supply
I have a number of electronic devices all of which require 12V DC input provided via a 2.1-5.5mm barrel jack.
Rather than have 3 separate AC to DC switching power supplies I'd like to use one power ...
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Why do power supplies get less efficient at high load?
Many PSUs follow the 80 PLUS standards, and it shows efficiency peaks at intermediate loads.
Power supplies are less efficient at low loads due to quiescent current. But why are they also less ...
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Why does higher voltage produce better torque from stepper motors?
I'm working with stepper motors and I have a question.
I have found that if I use a higher voltage switching source, I get better torques from the motor. Why is this?
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Design that outperforms buck converter
Above is quoted from here. I was just shocked to find out that the first image provides a much more efficient and simpler way to step down a voltage instead of using a buck converter circuit (second ...
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Power losses in Wire given end load and voltage at load
I'm trying to work out the efficiency of power transmission using a small LVDC system. I'm distributing 60VDC from a point and running it over quite a large cable (3-pair cable, 16AWG up to 500m one-...
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What is the limit for pairing batteries in series? What happens if we cross that limit?
Can we simply keep pairing more and more batteries in series configuration to produce higher and higher voltages? What are the consequences in doing so? Would the power from others series cells be ...
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Transformer efficiency with leading and lagging loads
I'm interested in how the efficiency of a transformer changes with the power factor of the load.
I know that in principle you can increase efficiency through power factor correction (i.e. making your ...
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Mismatched rating in Ah and Wh. Why is that?
My question concerns the apparent mismatch between the Wh rating and the Ah rating often found on batteries.
On one of my batteries the label says:
12V Leisure Battery TR350 TUDOR EXIDE DUAL 80Ah, ...
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How to calculate waste heat dissipation from a DC-to-DC-to-DC conversion
I am wondering how I can calculate the total combined heat dissipation (in watts) by two DC-DC converters in the following scenario;
In my case, I have a project where I have 12 volt DC, which gets ...
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Highest Efficiency/Lowest resulting heat from a DC/DC conversion
I have a 336VDC power source - it's a pretty unique piece of kit and won't be changing it. I'm looking to power around 500W of equipment from it at 48VDC.
However, I'm looking to do this using a DC/DC ...
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Running 400 Hz, 380 V spindle motor on 220 V, 3-phase VFD
I just (mistakenly) purchased a 380 V (400 Hz) spindle motor and I have a 220 V, 3-phase VFD. The manufacturer said the winding is a special configuration that performs equally well with either ...
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