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Im trying to understand the way a peltier modules behave as they are new and intriuing to me, I have ordered a few tec1-12705 units from china and done a little research trying to understand it.

Some discoveries indicate they are essentially a short circuit of 2 opposing metals with a 12v 6amp max safe running current. This coupled with having been informed they will consume whatever power you throw at them up to the max limit makes me suspect that they effectively have little to no impedence, making me question if series chaining these modules would effectively reduce any voltage or tecnically be consuming much of any energy them selves so much as they are mearly allowing the power to flow to ground freely, thus making me question:

Could I effectively chain 5 of these to recieve more efficiency out of the power delivered through it or am I mistaken in this?

Does the total power flow cause the effect ie 2 peltiers in series divide the voltage/amperage from 12v 4amps to 6v 2 amps each effectively being used per module or does the effective short allow the current to continue substantially unhindered.

I dont have alot to invest in experimenting or testing but have heard that these units do run more efficiently at lower voltages which makes me question what kind of test I could even manage to show the above.

In the experiments I have done I've found any standard power supply hooked directly to the unit tends to overheat likely as it is running at max flow, though I have also fried one module with 12v but too many amps, which seems to suggest to me these do not work the same way I am used to dealing with things related to power consumption....I figure this is related to the ressistance being low though but still leaves me questioning if I'd be better off running the modules from a motor working as a generator than trying to use it from a power supply.

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Then you need to read the specifications. From your previous question the specs read as follows...

enter image description here

Module resistance is 2.4ohms. So at 12V it will draw a max of 5 amps.

If you chain more (N) modules you can get it do more "work" but you need to increase the voltage by that number (xN) also to get each to perform at the same level. Or keep the voltage the same and each will perform at 1/N the level or power, with an attendant loss in TD.

Note also the resistance goes up markedly with temperature. This means the harder you make them work the less efficient they are. Or more importantly, you need to keep them as cool as you can.

Either way, the watts involved are large. You need heat-sinks and fans to get them to do anything real. Peltiers create a temperature difference between the sides. In order to get the cold side to the temperature you desire though you have to put IN a LOT of heat. Keeping the hot side at the desired reference temperature is 90% of the battle.

BTW: thanks for using capitalization this time.

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  • \$\begingroup\$ Thank you for that info, I had not seen the resistance value on the specs sheet i had, though am unclear on ohms correlatio. \$\endgroup\$ – user155835 Jul 13 '17 at 21:01
  • \$\begingroup\$ @user155835 ya it's a rather vague spec sheet and the curves don't seem to jibe with the values in the table. \$\endgroup\$ – Trevor_G Jul 13 '17 at 21:05
  • \$\begingroup\$ So I just downloaded an ohms calculator, and see it say that presuming i had 10 of these that 27.5 ohms from 12v is going to leave me just umder \$\endgroup\$ – user155835 Jul 13 '17 at 21:12
  • \$\begingroup\$ Ok. just downloaded an ohms calculator and by putting in 12v 2.75 ohms i got just under 0.5 amps so I presume this is all I am loosing from a series of 10? At nearly 6 amps required to improve performance 10 fold with such little addition, this sounds too good to be right... \$\endgroup\$ – user155835 Jul 13 '17 at 21:23
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    \$\begingroup\$ Don't forget they won't act like a resistor - as the temperature difference builds they will generate a voltage that will cancel some of the supply voltage. \$\endgroup\$ – Kevin White Jul 13 '17 at 22:50

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