Questions tagged [watts]
The unit of measurement and SI unit for power, named after James Watt. It is equivalent to energy flow per second or Joules/Second. In electrical terms \$ W = IR = I^2 * R = V^2/R \$
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Setting up mobile printing with laser printer
I am setting up mobile printing with Brother laser printer MFC-L5900DW, peak watts 1300. I am using deep cycle 100 amp battery, pure sine Sudokeji 2000/4000 watt inverter. I can't get printer to go ...
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How to Calculate UPS Batteries DC to AC Efficiency?
For simplicity's sake, we will use this APC UPS for example: https://www.apc.com/shop/id/en/products/APC-Power-Saving-Back-UPS-Pro-550/P-BR550GI. It has 330W rating, loaded with 66 Watt-Hour (Volt-Amp-...
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3answers
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How to estimate the temperature of a filament?
I would like to know how I can estimate/calculate the temperature of a heated filament.
For example, the filament (rhenium) is 0.2mm in diameter and heated with a voltage of 6.4V and a current of 2....
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Calculate the needed mAh to heat a flat coil for at least 2 hours [closed]
First of all, I want to let you know that I am very new to this profession. That's why I am asking you kindly to not use any profession related words, because I have very difficulties in understanding ...
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1answer
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How do I pick a suitable battery for my sensor?
I'm very new to electronics, and I have a sensor which is being powered by 2 batteries in series, each 6V/3.5Ah. I believe this means the total Watt Hours is 6x3.5x2 = 42Wh. When the sensor started, ...
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How does a 5,000 watt hub motor differ from a 4,000 watt hub motor (Both BLDCs), when powered by a 72V 100Ah Lithium ion battery?
I'm trying to design a motorcycle conversion kit for an underprivileged population in a rural area. I'm currently looking at potential hub motors to be powered by my selected battery (as mentioned in ...
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1answer
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Understanding relation between energy use, watts and amps
I'm looking into air conditioners and I've been unable to fully understand the relation between watts, amps and the energy ratings (in this case, the one used in the United States, the yellow Energy ...
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1answer
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Real consumption of SMD5050 Led Strips
I'm building my home lights with an SMD5050 Led strips.
And I'm completely lost after comparing specs consumptions with real measured data.
So on, I have 5 stripes and 1-to-5 Splitter from my ...
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3answers
188 views
Max watt bulb for an old “660w 250v” table lamp?
I have an old table lamp that's imprinted "LEVITON / MADE IN USA / 660W 250V / LAMP HOLDER".
I'm used to lamps with stickers that specifically tell me what max-watt bulbs I can use, usually 60W, 75W,...
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1answer
36 views
Odd problem with PSU [closed]
I don't know a much about electronics so please if you choose to help, layman terms would be appreciated.
I have an old 550w PC PSU. I have used it previously with an electronic air pump to pump up ...
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58 views
Is there any device or way to measure how many watts a computer's processor is using? [closed]
I know there's a device to measure how many watts a computer is using, you get an energy meter you plug the computer into it and it tells you
But I'm interested in finding out how many watts a ...
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Power consumption in watt for fluorescent lamps
I live in Egypt where the AC voltage is 220v.
Yesterday i bought two fluorescent lamps (60cm and 120cm).
I toke the following photos for the what is written on those lamps:
Please have a look to the ...
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1answer
81 views
What determines the colour temperature of a bulb?
There are various bulb products in the market, the temperature of the bulb determines the colour of the light emitted by the bulb.
For example
3000K is warm white (yellowish)
6000K is daylight (...
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Why is electricity consumption billed in watts and not amperes?
Basically the subject. Why would companies bill for wattage instead of amperes?
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What is the power consumption of a 12V adapter running 4 CPU fans?
I have a quick question here.
I am not a ECE guy and just a hobbyist trying to tinker while quarantined.
I have 4 CPU fans (120mm) laying around and I'm trying to re-purpose them as a small fan.
...
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1answer
35 views
Ist the radiant flux of a LED equal to the Power consumption - Power dissipated?
After I had my question How can I find the PPF of an LED? answred, I've started to look for some LEDs datasheets with the intention to find the radiant flux of then, but unfortunately all the ...
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Convert kWh to watts per m² [closed]
I am from a computer science background, I need some help with some electrical engineering problem.
Electricity consumption for a home in the last 56 days is 7561 kWh.
There are two floors. The ...
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1answer
65 views
How to build a 18650 battery pack without a spot welder?
I'm building an autonomous boat (which needs to get me a bottle of fine whisky from Scotland) for which I want to build a battery pack. The boat is currently powered by a cheap Li-ion battery pack, ...
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1answer
57 views
Can we get more current by reducing voltage on a power supply?
This is very basic question but I seem can't find the answer. All out there is theory, but no practical explanation about this.
Assume I have a 10V 2A power supply. So in theory it outputs power of ...
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2answers
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Using a US/UK voltage transformer at low end of appliance power range
I've purchased this from ebay, and the official vitaclay product spec page for the model indicates a power consumption range of 500-600W.
Transformers appear to come in either 500W or 1000W, but ...
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2answers
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Calculating the intensity of an electromagnetic wave
I’m a bit confused when it comes to calculating intensity versus energy of a wave.
If I’m given an electronmagnetic wave with an energy of 1 eV, how do I calculate its intensity ? I know intensity is ...
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How to calculate check practically POWER of SMPS required for desktop computer
How to calculate check practically POWER of SMPS required for desktop computers
I have 10 desktop pc in one PC i have a high end gaming gigabyte motherboard with AMD processor graphic card and ...
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1answer
67 views
How long can this motor run?
If I have a 48v 20Ah 1000w lithium ion battery, how long could it continually run a 48v 33Amp 2000w motor?
Also, how big of a battery would I need to have it run for 45mins at least?
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Measuring the instantaneous power consumption of phone
We can get the instantaneous current consumption and battery voltage via Android's API. So if we multiply those things, can we get the instantaneous power consumption of device? (P=V.I)
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How much power is needed to run these speakers?
I have couple of loudspeakers. Each is rated for:
RMS Power 60 watts
Power 75 watts
vc Imp 16 Ohms
I am going to build an audio amp for those but not sure how much power is needed.
I'm concerned ...
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1answer
30 views
Dynamic residential power system
I have a farm with solar panels. Right now, it is powering the house, and excess gets sold to the electric company. I was thinking that instead I could have the excess power bitcoin mining equipment. ...
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3answers
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How do I calculate the total wattage of a dc to dc circuit?
I am trying to figure out the total wattage of the below assumed dc to dc converter circuit block diagram.
Can I get it simply by just multiplying the total SUM of the system output voltages by total ...
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4answers
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How to know how much energy storage has powerbank? [closed]
I just looked to this question and I don't understand how to know how much Wh this powerbank has (click "Specifications" tab), because it has different output voltages and I don't know how to ...
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1answer
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Is it possible that the ampere high than the volt? [closed]
Is it possible that the ampere high than the volt?
for exemple if i have 5v and 6A
and how its possible that there is 30 watt and 5 volt charger?
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2answers
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Wireless fast charging in car
For my phone I want to wirelessly charge my devices as fast as possible using the cigaret socket (Automobile auxiliary power outlet).
I bought a wireless charging pad which on the back states.
input: ...
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3answers
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How will I know the power [dissipation] of resistor when buying resistors?
It is very basic question for many people. It is very easy to predict the resistance of a resistor with multimeter, but sometimes it comes with resistors which are slightly larger in size, such as, ...
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2answers
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why volt is needed for calculate watt? [closed]
hello i dont sure what is the difference between voltage ampere and watts.
voltage is only the potential difference between points high voltage will not cause to the electrons to move faster
so why ...
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107 views
How to find how many Amperes does a equipment use? [closed]
In the specification of this miner https://www.asicminervalue.com/miners/bitmain/antminer-s9j-14-5th it says it uses 1350W power with ...
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1answer
75 views
At what point a battery becomes a load
This has probably been asked before but I don't know how to search for it.
In a circuit where there are a battery and a variable power supply, what conditions have to be met in order for the battery ...
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2answers
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calculating Power
I wanted to ask, if I have a electrical component with a power rating of let's say 5W does this mean it would dissapate 10W after 2 hours and 15 W after 3 hours?? or is it correct to say it dissapates ...
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Wheelchair battery life calculation
Apologies because I'm sure this is an incredibly basic question and I've tried to work out the answer myself but I'm getting nowhere with it! I'm looking to get a powered trike attachment from my ...
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Why can a charger handle more watts at a higher voltage?
Why is it that my charger that has a rating of 100-240 volts and 1.3 amps can handle/input more watts at a higher voltage when doing the formula watts=volts x amps?
In addition, why can't it, at a ...
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24V LED Strip Circuit - Switch, Breaker & Wiring Size Requirement
I am running a long LED strip (24V, 21 meter, 0.6A per meter, so technically 13A).
The 24V PSU supplying power to the strips is to be connected to a switch that is rated 240V, 10A & 2400W.
...
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An overseas company is making a machine for me and they need to know whether I want 1,2 or 3 phase and what voltage
I'm in Quebec and the company making the machine is in China. The machine is an industrial sized T-Shirt sublimation machine that does two sided printing. So there's a large heated plate that is ...
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3answers
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What does the power rating of 10W mean?
When hair clippers or similar appliances are rated at, for example, 10W, does that mean 10W per hour or second? I'm trying to determine power of various hair clippers.
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2answers
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BLDC Motor max load
Hi i have a BLDC moter https://www.banggood.com/350W-48V-DC-Brushless-Motor-Geared-Ebike-Tricycle-Kit-Engine-Electric-Scooter-p-1419702.html?akmClientCountry=NL&rmmds=cart_middle_products&...
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1answer
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Wattage in US vs AU/EU household appliances
This oven is listed in both the US and Australia. You can see that it's the exact same model (BOV845). Yet if you open the specifications, the only difference is that the US model uses 1800 Watts ...
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1answer
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Batteries Spike in Watts and Amps Pulled with less than 50% Life
To give a background on this, I have been running tests to determine the actual lifespan of a 3 cell pack of some Samsung 18650s and Tesla 2170s at just above freezing. The Samsungs are INR18650-35E ...
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2answers
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If a 110 volt motor asks for 4W does that mean I will have to change the wall power? [closed]
I am new to electronics like motors so help on how to set this up would be awesome.
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1answer
133 views
Ammeter scale, not sure what my amp reading is
I have a basic multi-meter that I am using to measure amp on a load.
I am trying to figure out how much amps my small entertainment system draws. (LCD TV, PC, speakers.) I want to build a small DC ...
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1answer
205 views
How to replace push buttons on an intercom?
This is the intercom panel in my apartment, it's 30+ years old and I want to give it a face lift. The push-buttons are momentary, and I want to replace them using modern ones like these, but I'm not ...
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1answer
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built in charge controllers take amps they need?
Many devices have built in charge controllers that stop charging when battery is at 100%. I read several places that you can charge devices with the manufacturers recommended voltage and that higher ...
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3answers
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heat dissipation in watts of equipment in a box
Here is the situation, some electrical equipment will be in low ambient temperatures and I need to make it warmer so that there is no damage to it.
I want to calculate how much power in watts is ...
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When charging rechargable battery, should we care about watts and ignore voltage and current?
I know this might be a silly question, but it's from a beginner.
Let's say I want to charge a rechargable lithium-ion battery, so when I charge it should I only check the watts and ignore voltage and ...
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1answer
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How can a 12V 80Ah Battery be 1800W? Shouldn't it be 960W?
How can a 12V 80Ah Battery be 1800W? Shouldn't it be 960W?
I was looking for 12V 80Ah Deep Cycle Batteries on Amazon and most of them were 1800W.
Like this one: https://www.amazon.com/Cycle-Battery-...
