1. ## Overpowering a TEC

Like the title says, what happens when you overpower a TEC? Say it's rated for 15.6V and 9A and you put 24V and 10A through it? Will it go boom?

2. Or even just Putting more voltage than it's rated for... What would that do?

3. My guess is either:

a)It won't be cooled enough because of the increased heat output
b)Dies immediately
c)Starts on fire
d)Nothing (not really likely)

Doesn't sound like good options.

4. Cause I got my new 400W TEC and it's rated for 12V 26 or so amps. I was thinking of trying 12V + 5V = 17V * 10A = 170Watts. Which is what the TEC is suppose to be capable. I can't quite see what damage an increase in Voltage would do.

5. Originally Posted by Krow
Cause I got my new 400W TEC and it's rated for 12V 26 or so amps. I was thinking of trying 12V + 5V = 17V * 10A = 170Watts. Which is what the TEC is suppose to be capable. I can't quite see what damage an increase in Voltage would do.
If it is 26 amps stock and you put *more* voltage through it, it is going to put out *more* heat. I have no idea where you are getting 10A from.

6. I'm saying it's rated for 26 amps, but I will only be putting 10A through it, with 17V. The Voltage is the thing I'm only increasing beyond specs, and I'm actually doing less than half the current it's rated for.

7. the wires and soldering points will probably melt off. Don't try it.

The TEC will not suddenly pull less amps if you give it more voltage, it will pull more.

The 400W rating is at a certain voltage. At that voltage it will pull a certain amount of amps.

At higher voltage it will pull more amps and emit more that 400W of power...

it is not like the TEC will always emit 400W no matter what the voltage, it doesnt work like that

8. Well I dont think people are understanding my question.

It's rated for 12V and 26 Amps.

I will only ever be supplying 17V and 10A. There will be no where it can pull another 16A from.

9. how are you intending on limiting it to 10A???? some sort of transistor setup would be the only way i can think of

when you up the voltage you up the amps its trying to pull. full stop.

10. Well from what I've seen, a Molex has only 5A. I've checked it with a multimeter in the circuit of my TEC. So adding in a 5V source from the red wires, depending on the current rating of those wire, I'm assuming it's another 5A, it will only have ~10A to play with.

When I checked my current 136Watt TEC, it was only pulling 5A, and it was at 12V, it was rated for 15.6V at 9A. So if it were pulling all the current it wanted, wouldn't it be pulling a little less than 9A, with voltage limiting it?

Unless what you're saying is: If my powersupply has the current rating, it will deliever as much power as the TEC needs at 12V?

11. I think ur misunderstanding how electricity works.

amps arent given, they are drawn. voltage is given.

and what you say about the molex "having" only 5A means thats the most it can give. So if something tries to draw more that 5A the wire heats up and melts. not good.

also you cannot just "add" up voltages form the 12v and 5v lines to get 17v, voltage is potential difference and the potential difference between the 12v rail and the 0v rail is 12v and the same with the 5v, that is why they are called so. if you take the potential difference (voltage) between the 12v and 5v rails you will get 7v as that is the difference between them.

I think it i advisable that you do a little bit of reading before you go any further with your TEC as not knowing what you are doing with that kind of wattage is a fire waiting to happen.

12. If you have some reading material please PM me. Cause all I've read so far is what's on this forum, and a little bit I can find from google.

13. I cant think of anything specificaly off the top of my head but im sure a google for basic electronics will do you fine.

If I find any good ones 2moz I'll post em up here. Also maybe take a look over at the voltmodding and circuitry section of the forum : http://www.ocforums.com/forumdisplay.php?f=128

14. Thanks, Sam. I think you just saved a fire waiting to happen
But the good thing here is that he ASKED before trying this. As the old saying goes, theres no such thing as a stupid question...

You have to have a FIRM knowledge of electronics and what you're doing before you start exceeding specs. Because if you don't...

I know overdrawing amps on a rheostat for example, MAY be possible if you can cool the IC down enough with enough heat transfer but it's still not recommended. But this stuff, messing with 12v and 5v lines, is a mini nuke waiting to happen...

15. You can take a online class or take a class at the local community college, or even buy a book. Taking a guided/classroom class will really help a lot, just one semester is all it takes to get a good understanding of basic DC theory.

16. Originally Posted by Conumdrum
You can take a online class or take a class at the local community college, or even buy a book. Taking a guided/classroom class will really help a lot, just one semester is all it takes to get a good understanding of basic DC theory.
yeah, thats probs the best way to do it. You learn so much more and faster with hands on compared with reading a book. I find anyway.

17. There's a little thing called Ohms law that governs how electricity works. Just with a minor bit of surfing I've found this for you to look at.

http://www.angelfire.com/pa/baconbacon/page2.html

18. Well you did save me a butt load of trouble Sam, lastnight I did some testing and You were right about 12 and 5 being 7V. It's just for the longest time I've never seemed to grasp the differences between voltage and current. All I knew is current can kill. About 600mA and over will do it.(The reason I was thinking I could limit the current is because I thought that Molex was only able to do 5A, and they would add together, and also I've done OpAmps in my school course but that was 2 or 3 years back.)

I hooked my TEC up to the 12V (at 15.4V is what would give me 400Watts) and got just under 10 amps on it. So I seem to have an understanding better than I did when I asked the question, but it pops up a few more questions.

How do you calculate the current a TEC is going to draw when it is at a certain voltage without having readings. Just theoretical numbers. And is it a similar formula for any kind of device you use? Or is it specific to the TEC?

Lots of things were done lastnight which also made me think to make a quick connect for my Multimeter, so I don't have to keep making crap to do it with temporarily.

19. Originally Posted by Krow
Well you did save me a butt load of trouble Sam, lastnight I did some testing and You were right about 12 and 5 being 7V. It's just for the longest time I've never seemed to grasp the differences between voltage and current. All I knew is current can kill. About 600mA and over will do it.(The reason I was thinking I could limit the current is because I thought that Molex was only able to do 5A, and they would add together, and also I've done OpAmps in my school course but that was 2 or 3 years back.)

I hooked my TEC up to the 12V (at 15.4V is what would give me 400Watts) and got just under 10 amps on it. So I seem to have an understanding better than I did when I asked the question, but it pops up a few more questions.

How do you calculate the current a TEC is going to draw when it is at a certain voltage without having readings. Just theoretical numbers. And is it a similar formula for any kind of device you use? Or is it specific to the TEC?

Lots of things were done lastnight which also made me think to make a quick connect for my Multimeter, so I don't have to keep making crap to do it with temporarily.
Your right about current killing, thats why people really need to be carefull and sure of what your doing when messing with anything.

I dont think the current a TEC draws is linear, I remember when I was thinking about using TECs I downloaded a spreadsheet from somewhere which does all the calculations for you. I'll see if i still have it but I found it somewhere on one of the major forums.

but for any device OHMs law can be used. as linked above by chayos00. V=IR - Voltage = Current x Resistance. I think it would be good for you to read up on that from the link, it will do you well in all electronic situations.

20. Just a quick Side Question:

Is Vaseline pretty much the same thing as Die Electric grease or is there a benefit to using the latter over it.

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