resistors and watts

I know how to use ohms law to calculate what size resistor I need but what I really need to know is how to tell/calculate what watt rating I need to use whether it be 1/4, 1/2, 1/8, 1,10 and so on.

Posted by pattyshaw 7 years ago  |  last reply 6 years ago


convert to watt?

I am thinking of buying a acid battery. Its specification says that it is a 12 volt one and it's AHC@20 is 200. Can anybody calculate the watt output. I am not sure but AHC stands for Ampere hour capacity. Thanks RajibAzam

Asked by RajibA 4 years ago  |  last reply 4 years ago


5 watt LED

Hello, forgive me if this is not the right blog to post i was just not sure where to ask. i have a 5w led that came off a flash light i would like to either do my own flash light or install it in my house as a light, how can i do that and what do i need to power it, the only thing i know about the flash light is that is a 5 watt. also i dont know much about leds so if you guys can help that will be really cool. thanks

Posted by Nelson_Yepez 8 years ago  |  last reply 8 years ago


100 watt LEDs

Hi there I am wanting to drive 5 100 watt Cool white LEDs at half power total of 250 watts. Each LED spec is 32-34 volts DC @ 3.5 amps. Ideally I would like to drive from one power supply. or 2 at most, any advice would be welcome. please email me at tn21@live.co.uk

Posted by JohnT10 4 years ago  |  last reply 4 years ago


3000 watts inverter

Anyone knows how to build or make an inverter? a 3000watts inverter? can u give me the list of parts and picture diagram or schematic diagram? thanks guys

Asked by dangzching 1 year ago  |  last reply 1 year ago


conversion ratio of kva : watts?

Asked by lokoboy 8 years ago  |  last reply 8 years ago


4000 watts @ 220 volt?

How can i (step by step) generate 4000 watts and 220volt from a car alternator ?

Asked by nicobotha12345 9 years ago  |  last reply 2 years ago


Does anyone know the current best LED for Lumen vs. watts?

I would like to get a few of these for a project. It would be nice if there is a ebay seller that can give a deal. there was a guy that found this out, but that was a year ago.

Asked by JZ Price 9 years ago



LED help!!

Hello, forgive me if this is not the right blog to post i was just not sure where to ask. i have a 5w led that came off a flash light i would like to either do my on flash light or install it in my house as a light, how can i do that and what do i need to power it, the only thing i know about the flash light is that is a 5 watt. also i dont know much about leds so if you guys can help that will be really cool. thanks

Posted by Nelson_Yepez 8 years ago  |  last reply 8 years ago


I have 2 questions (in details) First: a way to measure Watts? Second: Rotating Camera Mount?

so as I said I have 2 questions. First: Is there a device that can measure the watts of an appliance? I just got a hold of a cheap generator (900w normal 1000w peak) and need to find out the wattage of some appliances. (None have stickers/plates on them at all to help me calculate it.) Second: Can anyone direct me to an instructable on motorized rotating camera mounts or anywhere that can show me how to build one? I want to be able to watch the sky from inside we get some nice weather here but hard to watch it from inside hehe.

Asked by BlueSuneLIght 7 years ago  |  last reply 7 years ago


what would happen if resistors of lower wattage are connected to a power supply of higher wattage?

The power supply i'm using for a circuit has a higher power rating than a bunch of resistors i bought. What would happen if they are all wired together in one circuit?

Asked by hmddeen 9 years ago  |  last reply 9 years ago


How do you work out the wattage of an amp?

I made the Ruby amp by runoffgroove (http://www.runoffgroove.com/ruby.html) and it's hooked up to a pc speaker with an 8ohm impedance, how would I go about finding the output wattage? And while you're at it if you have any amp-building knowledge to impart or good places to learn about amp circuits I'd appreciate it.

Asked by OptimumAlliance 3 years ago  |  last reply 3 years ago


How do watts, watt-hours, etc. relate to voltage, current, and resistance? Answered

I've worked with 12v and 5v a fair amount, and I've got a good understanding of Ohms law, series and parallel circuits, etc. But, I get a little sketchy when it comes to wattage ratings, KWHs, etc. and their relation to (now) my electric bill, (but hopefully soon to my off-grid, alternate power sources/power banks) and what I can handle as far as power consumption, etc. Any theory, links, book suggestions, practical examples, etc. will be GREATLY appreciated. Thanks so much in advance, everyone!

Asked by sykotik 9 years ago  |  last reply 9 years ago


5000 watts power inverter

5000 watts power inverter with the circuit diagram using SG3524

Asked by santos4eva 8 years ago  |  last reply 3 years ago


Please explain WATTS to me! Answered

 I know watts equal amps times volts. But why? What is the benefit? Hypothetically, I wanted charge a laptop with some batteries ( instead of with the charger cord). The charger cord says 65 watts or some such, but what does that tell me?  Is 65 watts the same as 13 volts at 5 amps? Or 13 amps with 5 volts? what voltage/amperage would I need to charge this laptop? Thanks!

Asked by nepheron 8 years ago  |  last reply 8 years ago


What is the maximum power (ohms/watts) available from a headphone port?

I happen to have a set of 8 ohm speakers (which say 20 watt max) and wondered about using them so I can listen to my mp3 player in the shower.

Asked by Andale_The_Great 7 years ago  |  last reply 7 years ago


Testing 3 Watt LED's

I recently purchased 13- 3 watt LED's. I'm trying to establish a high out-put LED light. I also purchased a LED Driver Transformer 48 Watt 120 Volt to 12v DC 4 Amp. First I would like to test each LED using the same divider. I'm thinking that if I create a voltage divider two 330 ohms to limit the current and reduce the voltage to about 6 volts that would allow me to test with the driver that I purchased. Secondly, will this driver be enough to drive all my LED's and would I have to reduce the voltage down too since it appears to push out enough wattage and amperage for the total number LED's I'm putting together? I'm building my circuit based on this video. http://www.youtube.com/watch?v=4qYZahe2s5o&NR;=1 Link to website data of 3 Watt LED. http://ledsupply.com/indusstar-1up.php Assistance would be greatly appreciated. Regards, 

Posted by lancruz 7 years ago  |  last reply 7 years ago


Testing a 3 watt LED? Answered

I recently purchased 13- 3 watt LED's. I'm trying to establish a high out-put LED light. I also purchased a LED Driver Transformer 48 Watt 120 Volt to 12v DC 4 Amp. First I would like to test each LED using the same divider. I'm thinking that if I create a voltage divider two 330 ohms to limit the current and reduce the voltage to about 6 volts that would allow me to test with the driver that I purchased. Secondly, will this driver be enough to drive all my LED's and would I have to reduce the voltage down too since it appears to push out enough wattage and amperage for the total number LED's I'm putting together? I'm building my circuit based on this video. http://www.youtube.com/watch?v=4qYZahe2s5o&NR;=1 Link to website data of 3 Watt LED. http://ledsupply.com/indusstar-1up.php Assistance would be greatly appreciated. Regards, 

Asked by lancruz 7 years ago  |  last reply 7 years ago


LED 3 Watt Testing

I recently purchased 13- 3 watt LED's.  I'm trying to establish a high out put LED light.  I also purchased a LED Driver Transformer 48 Watt 120 Volt to 12v DC 4 Amp. First I would like to test each LED using the same divider.  I'm thinking that if I create a voltage divider two 330 ohms to limit the current and reduce the voltage to about 6 volts that would allow me to test with the driver that I purchased.  Secondly, will this driver be enough to drive all my LED's and would I have to reduce the voltage down too since it appears to push out enough wattage and amperage for the total number LED's I'm putting together?   I'm building my circuit based on this video. http://www.youtube.com/watch?v=4qYZahe2s5o&NR;=1   Assistance would be greatly appreciated.  Regards,

Posted by lancruz 7 years ago  |  last reply 7 years ago


Need a 30 watt "LASER"

Looking for an inexpensive laser cutting/engraving system. I will be taking it apart and  customizing it to fit onto another machine.  Currently, we have a rotating blade to cut sheets of material, but this set-up causes many issues.  A contact free solution would be best.  So I want to mount the laser carriage above the cutting area; the rest of the laser parts will be contained in a metal cabinet under the machine.  The laser would need to be able to travel 12-16 inches in 1-2 seconds and cut through 1-5 mil paper/poly material. I have a fair amount of experience with lasers, I have know how to sight them in and understand the technology.  We currently have 45, 100 and 400 watt galvo head lasers, as well as a 90 watt XY laser set-up. So, what website would you direct me to, to purchase an inexpensive laser system?

Posted by benjaminleebates 3 years ago  |  last reply 3 years ago


10 Watt LED Circuit

I am a software developer by trade and have little or no experience regarding LED and/or electronic designs. I am hoping someone here can help with a project I am working on using high brightness LEDs. I have studied several 'instructables' and specifically dan's "Circuits for using High Power LED's." My project consists of a few high brightness LEDs that will be placed in a high ceiling room with the brightness controlled by a microcontroller based on the light in the room (time of day, sun in window, etc). The microcontroller will use photocells to determine the brightness in the room and then adjust the LED using PWM pins. The LED is 10 watt and approximately 450 lumens. Attached is a circuit I drew as a starting point and would like help in determining if it will work, I am close or does it need to be trashed. I am not sure what the value for the resistor should be. Below are some calculations but not sure if I am on the right track or not. No need to be kind, I am more interested in getting it right and not losing any 'magic puffs of smoke' from any of the components. Here are the specs: LED IF: 1.6 A Peak Forward Current: 1.7 A Forward Voltage: 8 V LM350 (heavy duty version of LM317 IO_MAX: 4.5 A 1.2 - 25 V adjustable regulator BC337-40 Collection Current - Continuous: 800 mA dc Total Device Dissipation: 625 mW Resistor: 5W or 10W Voltage Amp Ohms Watt 8 1.60 5.0 12.8 8 0.80 10.0 10.0 8 1.10 7.5 8.5 Note: LED and components will have adequate heat sinks.

Posted by desnotes 9 years ago  |  last reply 3 months ago


How do I measure Wattage? Answered

Alright, in my cold fusion set up I need to measure the watts going in and the watts going out.  How can I do that?

Asked by Kalrag 8 years ago  |  last reply 8 years ago


wattage

I was out buying the parts for the free electricity from telephone port in wall, but the resistors have no wattage posted. The man at the electronics store said he needs the wattage for the correct resistors.

Posted by 3l3ctr1cman 11 years ago  |  last reply 11 years ago


transformer input Answered

I have a transformer with 13v input can i give it 240v without it melting and can you please tell me the math of transformers  am new and any information helps

Asked by mohamed amin 2 years ago  |  last reply 2 years ago


How can I combine my 400watt and 750watt AC/DC inverters to get 1000+ wattage out of them?

I have both inverters and they both still work.  Instead of going to buy an expensive 1000 plus watt inverter I'm looking for a simple way to just combine the two I have to handle the wattage I need them for.  I go camping a lot and I like having hot coffee in the mornings, so I need an inverter to handle a coffee pot.  I could stoke the fire and put a perculator over it or crank up the generator and plug in the pot but I'm a simple guy who likes simply plugging in the coffee pot to my truck! 

Asked by WildBill76 9 years ago  |  last reply 9 years ago


Mismatching speaker wattage?

Hey guys, So I've recently gotten into making DIY speaker systems, but I'm having trouble understanding the whole ordeal about wattage and ohms. I have four speakers I managed to salvage from some old speaker systems that I got from an old thrift shop. I have two 15W 4ohm speakers, a 20W 8ohm speaker and a 2W 8ohm speaker (but I don't think I'll find a use for that one, I'm not sure) I plan on buying the Lepai LP-2020A+ amplifier, it's a two channel amp and delivers 20W/ch with impedance of 4-8ohms. What I want to know is what set up would be best with what I have? Can I run the two 4 ohm speakers on 1 channel even though they would draw 30W of power? I'm a bit new at this, and my understanding is still a bit unclear so if anyone could please explain, I would very much appreciate it :) Thank you

Asked by VoicesOnAir 5 years ago  |  last reply 5 years ago


KWH , Watt giving me a headache...

Morning Guys Need a bit of help with the maths. Hoping to run a fridge on a inverter / battery / solar panel. If it has a energy consumption of 0.43 KWH, I think it would be about 43 watts not sure here. What size battery and solar panel would I need? Big Love Chris

Asked by Handyperson1 3 years ago  |  last reply 3 years ago


Do Amps matter?!?

Ok, I need a charger for my motorolla two way radios. I have the dock, only need a DC power supply. on one of them it states "18Volts DC +/- 20%, 15.3 watts" .Lets say I get 18VDC 1amp power supply, that's 18W,it means it's an overkill? or 15V 2Amps? As I understand, usually amps don't matter, as the item draws as much as it needs, but since it is a charger.. Cheers for the teh help!

Asked by zhgutas 7 years ago  |  last reply 7 years ago


Airbrush compressor TC-20, how many watts???

Hi guys, i recently bought a mini compressor for cake decorating. Its a "ABD TC-20" and i bought it at TCPglobal. Problem is, i dont know how many Watts it uses! You see, i bought it as a pressent for my wife. "Nice? Yes!" "Bought with my nose and not my brain? Yes! Im living in Holland, and our network works on 220volt at 50Hz. The compressor i bought works on american standerd, 110volt at 60hz. So i need a converter to make the machine work without frying its circuits... If i buy a converter specificaly for this machine, it has to have the right amount of Watts. i know, i can buy a converter that handles Watts in the range of 1000Watts, cuzz more watts on a converter is better, but than i'd have to buy one thats quite expensive. Because if the compressor only uses, lets say, 50 watts, i could buy one that has a max of about 100 / 150 for a waaaay lesser price than the one thats more powerfull. It would be 50EU for the smaller converter against 200EU or more for the bigger one. So, if you happen to know something on this subject, i would be more than happy with any info you've got ;-) greets! P.S. At the moment i wrote this, the package is stil on its way from america to my house. So i dont have a box or machine sticker to sneak the info i need from...

Posted by AriedeB 6 years ago  |  last reply 6 years ago


SSR and a hotplate

Dumb question. Have a heating plate that uses 1100 watts and runs on 120 volts ac. if 1100 watss / 120 volts = more or less 10amps, Could I safely use a 10 amp rated ssr aka solid state relay or use something higher.

Posted by Computothought 3 years ago  |  last reply 3 years ago


What is a 4 pin power connector that can handle a lot of current? Answered

For a project powering red, blue, and green LEDs, with a common positive, I am hoping to power around 250 LEDs with around 5 amps. This means that each wire needs to be able to handle 5 amps of current at 12 volts (or 60 Watts), with the other three wires acting as grounds. I've looked at PC peripheral molex connectors, capable of handling around 5-8 amps however that is over all four wires. I need something stronger, most molex connectors use 20 gauge wire (which handles 1.5 amps), while the national electrical code suggests a 14 gauge wire to handle 5.9 Amps. It doesn't matter to me what the connector is supposed to be used for, if it's an audio plug, power plug, or whatever, this project will be very jerry-rigged. I would greatly appreciate any suggestions for a suitable plug.

Asked by QuackMasterDan 9 years ago  |  last reply 9 years ago


how many watts and hp can?

Asked by tazerl494 8 years ago  |  last reply 8 years ago


What is a 1/4 watt resistor? Answered

Alright, So I know the basics about resistors and what-not, but as I was buying beginner supplies, I noticed there were resistors in OHMs and Watts, What's the difference between the two? And like, can the unit Watt be transfered into OHMs? And which one would I use when my general area of working would be around basic LED work and noob stuff like that xD?

Asked by E D E N 9 years ago  |  last reply 22 days ago


MXDL 3 watt joule thief? Answered

Can anybody make sense of the joule thief inside a MXDL 3 watt luxeon torch? I can post a rough picture of it if needed.

Asked by .Unknown. 8 years ago  |  last reply 8 years ago


100 watt sub woofer amp

I'm looking for or to make a 100 watt amp, I can't seem to find any. If you know where i can find one online or a schematic to build one please let me know! Also is it possible to resist or lower the amps from an amplifier or will I have to specifically get a 30 watt amp for the mid range speaker. I am attempting an "led music box on steroids" project hahaha.... basically what I am going to do is make a clear plastic box and put leds and speakers and a 6" sub in it. Kinda bored and looking for a fun project and this came to mind. I'm open to any suggestions to make it better or ideas on how to power the speakers. Thank you in advance! The sub woofer I'm looking to power http://www.electronix.com/100-watt-woofer-speaker-ohm-p-13521.html and the mid range speaker http://www.electronix.com/30-watt-midrange-speaker-p-13507.html Might think about putting a tweeter in too

Posted by zcm87 7 years ago  |  last reply 6 years ago


using 1 watt LEDs with a 4017

I want to build a chaser type light array using a 4017 counter divider circuit, 555 timer and the ever popular 1 watt luxeon LEDs, but I don't think that the 4017, or the 555 can withstand the current that will be going through them. I know in most cases you can simply toss a heatsink on the component and it will be fine, but I don't know if this will work with the ICs. https://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId;=10001&catalogId;=10001&productId;=12749Here is the spec sheet for the 4017. Thanks

Posted by John Culbertson 11 years ago  |  last reply 10 years ago


Generating a Couple of Watts Using Urine?

Hello, I recently came across a paper written by a researcher from a Scottish University about generating electricity directly from urine in a fuel cell and I was wondering if a larger version could be built to generate around 2 watts.  The power per square cm is around 1.5mW so even at 1mW I would need 2000 cm-sq so I think it would be easier to build a stack of cells instead of one or 2 large cells. I'd like to attach the paper but it's one which you need to pay for though I got it for free, could a moderator let me know what to do?  It was written by a Shanwen Tao and called 'A Direct Urea Fuel Cell' DOI: 10.1039/b924786f Another idea I had was to use a small PV setup to generate hydrogen from urine and then store the gas so that it can be used in a hydrogen fuel cell.  I've had some difficulty in trying a to find a cheap fuel cell but then I came across this page: http://www.mtmscientific.com/fuelcell.html Are there any really simple ways of building a fuel cell? I'm posting this here to see if anyone can help me come up with a viable design and maybe even build it for me.  I can pay you for your time and effort; though as a student I do have a tight budget to stick to. Any help, advice and ideas will be very much appreciated. Thank-You

Posted by jezym108 5 years ago  |  last reply 5 years ago


8 Watt Guitar Amp Help

I've been fartin around with electric and acoustic guitars for about the past 5 years. Only now am i getting decent (by no means good, but better, i guess...). I've been wanting to make a small amp with a small speaker for some time now.I saw this circuit the other day. Its VERY simple.http://www.aaroncake.net/circuits/amp.aspIt says to reverse the values of R1 and R3 for use as a guitar amp. there's some other stuff too. I was going to see if i could pick the stuff up at radioshack tomorrow, and maybe make it an after-work project for the week. Maybe cut up some wood and make a nice box for it. 1)Do you think these parts would be available at radioshack? and what do i need to look for if i cant find the exact IC? 2)Any special soldering tips? 3)What kind of pot do i need to add, and where, for a volume knob?4)Is there any extra things you think that needs to be added?5)Are those triangle things grounds? as in 12v negative? And what about the other wire from the guitar? 6)Also, what ohmage speaker do i need to use? What am i looking for in a speaker?7)Will 8 AA batteries do the job?8)Do i need to add like a fuse or something somewhere? Going straight into the IC...i dont know. If anyone knows of simpler or better designs, let me know. I seem to really [insert proper four-letter word here] up electronic things. I think thats all the questions i have here. To respond you can just go like..1)i think that....like that. Hopefully that will make it easier to answer all my ignorant questions.Thank you!Jason(sorry if i seem like a a$$ here. Its 1:35am, I've been looking this stuff up for two hours, and i dont feel like i got any further....)And since i dont have a suitable picture, have yourself a look at my LEGO steam engine: (after the third try of trying to post the video with unsuccessful results, i realized that i was posting the embed code int eh URL place...need....sleep....)

Posted by John Smith 10 years ago  |  last reply 10 years ago


Is it true? 2 watt led has 1 diode, and 3 watt led 2 diodes? Answered

Is it true? 2 watt led has 1 diode, and 3 watt led 2 diodes? or can a 3 watt 700ma have both?

Asked by MistaMasta 5 years ago  |  last reply 5 years ago


Designing a Solar powered sign. Need help determining how many watt solar panel? Answered

I am trying to run a sign off of solar power. The sign has 40 LED modules. Each module has 3 individual leds. The specs for each module are 12v, consumes .7 watts, and 50 mA. Multiplying watts and amps by the number of modules you get 28 watts and 2 amps. I'm looking at solar panels from walmart and they come in 10,15,20,30 ,60 watt panels. If the sign is ran 12 hours a night(6pm-6am), That means 28 watts x 12 hours = 336 watts used per night. If the solar panel gets 8 hours of sunlight to charge(8am-4pm), that means 336 watts/ 8 hours means I need a 42 watt solar panel? Also, how big of a battery do I need? 2 amps x 12 hours = 24 AmpHour battery? EDIT: I'm going to use a 12V timer relay so I can run the LEDs from 6-11 pm and 5-7 am. This decreases the on time to 7 hours and 196 watts. With 8 hours of sunlight, that means 25 watt charge. Also 2 amps x 7 hours = 14 AmpHour battery. 

Asked by tallemertes 3 years ago  |  last reply 3 years ago


how many watts does my rock tumbler use?

I just bought a rock tumbler off ebay. the brand name is "chicago power tools". its a basic 3lb capasity rock tumbler/ lapidary rotary tool. now, because i live in australia, i have a problem, my power outlets produce 240v , and the rock tumbler can only take 120v, and so when i pluged it into a power adaptor (us-aus), the transformer gegan to work, then overheated and produced smoke, fortunately it still works . now, i am going to go and buy a stepdown transformer and have learnt that if the device is using more than 90% of what the transformer supplies, the transformer will overheat or break or something. now, on my tumbler, and everywhere a description for it is put, it mentions nothing on wattage consumption, and so i am asking , how many watts will it use so i may accordingly select a stepdown transformer for it.

Asked by oldmanbeefjerky 8 years ago  |  last reply 8 years ago


Resistor power rating increase in parallel?

Let's say I need to have a resistor in a circuit rated for 10 Watts. If I had two resistors rated for 5 W, could I wire them in parallel to make the equivalent power rating 10 W? I know my resistance will be different but I'm not sure how the power rating would differ.

Asked by ishmal1103 4 years ago  |  last reply 2 years ago


I have a simple question about watts... Answered

Watts = amps times volts, correct? So if I had a laptop that charged with a 60 watt power supply, could I: -Charge it with 10 amps at 6 volts? (that is the same as 60 watts) -Charge it with 6 amps at 10 volts? (that is ALSO the same as 60 watts) -Charge it with 5 amps at 12 volts? (that is ALSO the same as 60 watts) -ect... Watts is just how much 'energy' passes a single point every second (or whatever), so it doesn't matter how you get the watts, watts is still watts? I'm still trying to grasp the whole concept of watts, so yours answers are infinitely appreciated!!!

Asked by nepheron 8 years ago  |  last reply 8 years ago


What are the specs of microwave transformer? Answered

I am trying to build an AC arc welder from transformers. I need to know how many amps, volts and watts a normal microwave transformer outputs because i am trying to use different transformers, as i don't have two microwaves on hand. -Thank You

Asked by shammallamaman 9 years ago  |  last reply 2 months ago


Is it reasonable to convert energy to power over time?

I have recently been talking with another person on instructables about converting 33 megajoules into a standard comparable electric unit, watts.  Now the formula for joules just so happens to be watts times seconds, but he still thinks this is wrong.  He says I can't just assume time.  Now I can assume any amount of power for any amount of time I wan't to as long as it adds up to 33,000,000 joules in the end right.  So if I wan't to consume one watt every second, then I have to set the amount of time as 33,000,000 seconds or roughly 9,166.7 hours.  This all seems fine to me right, because one watt for 33,000,000 seconds is equivalent to 33 megajoules. Now I originally didn't understand all of this so I just fumbled around and ended up converting to hp and got roughly 12, which is very close for being a rounded off number.  It comes out over one hour to equal just over 32 megajoules.   I can't seem to understand what the problem is, the DEFINITION OF ENERGY/WORK IS POWER *(OR OVER THE PERIOD OF) TIME Is there really such flawed logic here that "joules could be converted to cubic meters?"

Asked by jj.inc 7 years ago  |  last reply 7 years ago


can you answer a few questions i have on SLA batteries? Answered

1.As you can see in the diagram i have eight 4.5 AH SLA batteries joined together to make four 12 volt 9 AH batteries. how would i incorporate my bigger 7 AH 6 volt SLA into this? 2.Is my math correct that i did up in the corner? 3.Does an amp an hour storage in a battery mean it will supply one amp for one hour? 4.If so and my math is correct i would have 516 watts of power for one hour stored in these batteries?

Asked by harry88 5 years ago  |  last reply 5 years ago


How do you use a solar panel to light a 10w light bulb at night? And what kind of a solar panel would I need?

I want to make my own solar panel (a small one) for a school project, but I also want it to be useful for after the project as well. I need a small light to light something outside, but at night (because, obviously, I can see during the day). So apparently you need a battery to store the energy during the day, and a charge controller is really important. I've found a lot of useful sites and videos (and instructables) that show how to make solar panels, and a few that show how to connect the solar panel directly to a light bulb, but I can't seem to find anything that clearly explains the battery and charge controller part. Please note that I know nothing about the technology of solar panels, watts, volts, etc., and have never taken apart or made even a simple electronic device of any sort. The most experience I had with this stuff was when I made a small circuit with a light bulb, battery, and alligator clips sometime around the sixth grade, but I have no idea how all that works and all the numbers that you need to keep in mind (I did learn the basics a couple years back, but I've forgotten everything), so when I find brief explanations online that say you need a battery, charge controller, and you need to somehow calculate the correct capacity and voltage, I'm totally lost. Can someone please help me out and explain? Or at least provide a useful link or something? I've scoured the Internet, trust me. Unfortunately, I was unable to find anything clear or something in a "How-to" format. Also, I'm flexible on the 10w thing. A 10w light bulb was just the lowest I could find and I thought the lower the better. So what kind of a battery and solar panel (how many watts/volts, etc) would I need? Low cost is ideal.

Asked by a Canadian 5 years ago  |  last reply 4 years ago


What's the difference between volts and watts in an electric scooter motor? Answered

I'm hoping to build my own electric scooter in the summer once I know more about the motrs, batteries, etc I've found two 500w electric motors on eBay. One's 24v and the other's 48v. what's the difference? why would they need different voltages? I can't remember that particular lesson about electronics from my school lesson lol.?

Asked by JackIsted 7 years ago  |  last reply 4 years ago


1 watt Frequency Doubled Violet Laser

I want to make a 1 watt violet laser, by using a 1 watt 808 nm laser and channeling the laser through a KTP crystal. Judging from my humble knowledge of second harmonic generation, That should create a 1 watt violet laser beam. Correct?

Posted by Nexoid 8 years ago  |  last reply 8 years ago