# Help quick please noob question

Discussion in 'General Electronics Discussion' started by Nooby213, Jun 23, 2011.

1. ### Nooby213

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Jun 20, 2011
hey guys ive been wondering since if got a little project going on, is it possible to have too much watts going in? i mean like is more watts good or can it cause damage if somethings not designed to take that much watts, i really dont understand watts

443
3
Jun 10, 2011
Wattage is a measure of power, which is a measure of energy per unit time. If you dissipate too much power, you could ruin something, usually by something heating up, melting, and destroying its function. So, yes, it's possible to ruin something by putting too much power in.

3. ### rob_croxford

262
0
Aug 3, 2010
A watt is the measurement of Power which is calculated by voltage multiplied by current.

Exceeding the Watt rating of a device cannot only permantly damage it but it can also cause excesive heat resulting in fires.

4. ### davennModerator

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Sep 5, 2009
things need to be cleared up here

Firstly tell us what your project is,
what is the power supply requirements in volts and amps

I suspect what you may be getting at that the others didnt pick up on is....

if you have a gadget that requires say 12V @ 1A = 12W
what happens if you connect a power supply that is capable of supplying 12V @ say 2Amps (24W).

The answer ... Nothing. the gadget will draw its 1 Amp and thats it.
you could feed it with a 12V power supply capable of 100A the gadget is still only going to draw its 1A

cheers
Dave

5. ### davennModerator

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Sep 5, 2009
no, not quite correct daddles, see my previous statement.

and just think of the amount of power that can say be supplied to your household
I think your in the USA so 110V and say your 2000W heater or aircon thats 18A
but yet your tiny plugpack to charge your mobile phone is only drawing 500mA (0.5A) from the same power system.

The problem comes if you input excessive voltage than what the gadget requires.

cheers
Dave

443
3
Jun 10, 2011
Sorry, Dave, I stand by my statement -- it's possible to ruin anything by putting too much power in. That's the answer to the question the OP asked. And, it applies to any closed thermodynamic system, even the US Congress. It's irrelevant how that power is increased. There was no statement about e.g. a constant voltage.

Now, of course I know where you were coming from, so from that perspective your statements are correct too. However, until the OP clarifies his questions, the rest is speculation at this point.

7. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,497
2,838
Jan 21, 2010
A case in point is the typical switchmode power supply.

As you reduce the input voltage the input current increases and with it the power dissipation due to I^2R losses.

Low input voltage is a very good way of killing some switchmode power supplies (I could mention a power supply made by Hewlett Packard in the mid to late 80's that was guaranteed to expire if you had a brownout).

However, (to straddle the fence) the problem is still excessive current. Even problems caused by excessive voltage (such as breakdown of junctions) really cause problems due to excessive current.

But let's not start counting the number of angels that can fit on a pinhead.

Yes, excessive power can (and at some point will) damage stuff.

8. ### Laplace

1,252
184
Apr 4, 2010
Let's say you have a 'box' in which you build your project. Measure the power entering the box (volts x amps). Then measure the power leaving the box. The difference between the power in and power out is the power lost in the box. This lost power is converted into heat within the box. Unless you arrange some way for this heat to be conducted outside the box, the contents of the box will rise in temperature to the point of incineration. Note that a more complete balancing of power will consider all forms of electromagnetic radiation and mechanical work but these are usually of negligible significance.

9. ### davennModerator

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Sep 5, 2009

Last edited: Jun 24, 2011
10. ### davennModerator

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Sep 5, 2009
Sorry Daddles, I am stirring a bit,

but it looks from some of your posts that you have electronics experience.
you really shouldnt have fallen into the OP's trap of using the same incorrect terminology

hence why I tried to clarify things to him in my first post... to get him to state the V and I required by the project/device instead of incorrectly using the term power.

unfortunately he has yet to respond and it has left the rest of us to bander about the use of terminology

peace bro

Dave

443
3
Jun 10, 2011
davenn: Ha! I was probably destroying components with too much power when you were still in diapers. But we probably both know enough to be dangerous, so what's really needed is an OP who doesn't come in, drop a turd on the ground, then run off...

12. ### davennModerator

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Sep 5, 2009
ahhh maybe you were dunno ? I'm in excess of 50 and I started reasonably young maybe you are 60++

yeah ya get those flybyes that dont bother coming back. what they do is ask the same Q of 4 different forums and dont bother rechecking all of them to see if anyone has answered. or the prefer the answer on another forum and down worry about the rest without even a thankyou

Dave

443
3
Jun 10, 2011
OK, you probably weren't in diapers, but you weren't chasing girls yet (well, for the teenage reason).

I've got a science background and I'm an electrical hobbyist, so I'll definitely defer to your electrical expertise (and I hope to tap some of that knowledge with later questions). Just don't slip on the turds...

14. ### davennModerator

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Sep 5, 2009
its the good thing about forums like this we all have strengths in various fields

gosh I look at some of the responses steve and res give to ppl and I realise how little I understand the theory of some subjects

I'm the construction type. ... give me the cct and parts and I will build you anything
but tell you the "fine" details of how it works and I will probably stumble
I did my trade with telecom in New Zealand in the late 70's till redundancy in the late 80's worked for myself during the 90's doing tv,vcr, telephone, computer work and at the same time put myself through a BSc in geology at university (one of my really major interests!!!!) In 2000 I came to Australia cuz of the lack of work in NZ.
My work nowdays is audio/video and fastfood takeaway drivethrough radio systems

My main home electronics work is in amateur radio and primarily on 144MHz and well up into the microwave bands. 24GHz is my current max operating freq. I have some surplus 50GHz gear that I need to convert to our 47GHz band, its gonna take some serious effort
its all build your own gear cuz there isnt anything commercial on those freqs for amateur use.

enough history from me hahahaha

take care
Dave
VK2TDN
check out my www pages (google search callsign)

Last edited: Jun 25, 2011
15. ### TBennettcc

292
2
Dec 4, 2010
Good to see another amateur on the forums here, Dave.

I'm actually getting ready to go do Field Day with my club. Our club call will be W4LX. My personal call is KJ4MUY. Will you be operating for Field Day?

It's a shame you're not on the HF bands, it'd be great to have a ragchew. Then again, I don't exactly have a working antenna, so it's hard for me to get on the radio at my QTH.

73,

Tim

16. ### davennModerator

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Sep 5, 2009
hey Tim,

ahhhh cool hahaha talk to any of my ham friends and they will say.... "ohhh dave yeah... anything below 1GHz is DC to him" hahaha
gosh I havent had a QSO on 40m for 2 years. When they did away with the CW requirement 5 odd yrs ago in OZ, I had a bit of a blast on 40 for a year or 2 but slowly lost interest and went back up to the uWave bands. I love the challenge of getting gear running on those freqs
I still have a 40m inverted V in the air, just in case.....

We just had our winter VHF/UHF field day last weekend 18/19 june

just looked you up on QRZ.com, wow look at all those waterways around you !!
any worries about global warming and rising sea level ?

cheers
Dave

17. ### TBennettcc

292
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Dec 4, 2010
Not really worried about "climate change", as they seem to be calling it now...

More of a worry here are the hurricanes. Depending on how the hurricane approaches the waterway, it's possible that it will gather up a lot of water and push it up the river, flooding the river and canals. This is referred to as 'storm surge'. Had a close call here August 13th, 2004. Hurricane Charley. The eye of the storm passed I think within about 15 miles of us. The storm turned north at the last second. The people north of us were in bad shape for a while. I didn't get into ham radio until June 2009, so I didn't know about any of the emergency communications that might have been going on at the time.

Cape Coral was developed by the Rosen Brothers in the 1950's. From what I understand, it was a scam. They paid pushy salesmen to fly potential customers over what was then mostly swamp land, cleared out by digging the canals and piling fill dirt to make the land. When my parents moved here in 1982, the main road through the area was two lanes, and there was no interstate. Today, the main road is six lanes and we have a main interstate less than 20 miles away. Amazing how this place took off...

I think might be interesting one day to be able to make my own microwave gear and talk on it. I'm looking at joining the military here, and hoping I can get some kind of electrical education, and then be a board-level repairman for them. I think that would be a lot of good experience. Hell, I might even be able to snag an EE degree out of it! Who knows?!