overclocker333

How many amps will this tec use?

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If this tec is undervolted to 12 volts... how many amps will it use? How would I calculate the amps @ 12 volts?

The eBay guy is calling it a 168 watt tec... so I guess he's just using 10.5 amps x 16 volts for the 168 watt rating. Is there any way to tell what the qMax would be @ 12 volts with this limited info?

But what I really need to know is how many amps will it use @ 12 volts?


http://cgi.ebay.com/ws/eBayISAPI.dll...ayphotohosting



Model CP1-12710

40mm x 40mm x 3.3mm
Operates from 0-16 volts DC and 0-10.5 amps
Operates from -60 deg C to +180 deg C
Each device is fully inspected and tested
Fitted with 6-inch insulated leads
Perimeter sealed for moisture protection
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ChielScape

with those 16v and 10.5 A you can calculate the resistance, and with that the amperage at 12v.

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overclocker333

Hmmmm... I'm a little rusty on my Ohm's Law... can you give me a refresher?

overclocker333

Ohm's law: I =V/R


10.5 amps/16 volts =.65625 ohms x 12volts =7.875 amps?

So... it is directly proportional to the 75% undervolting amount?

ChielScape

http://ourworld.compuserve.com/homep...en/ohmslaw.htm

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Hephasteus

14 amps

overclocker333

Really... more amps?

Is this a joke?

Would you mind showing or telling me why?

overclocker333

94.5 watts & 7.875 amps!!!


Thanks!!!

Your the best!!!

That is so cool!!!

Scarlet Infidel

Er, it isn't quite as simple as this. The resistance will vary with relation to temperature and load. However that is a decent way of working out a ball park figure.

Best to find a data sheet that matches this one should be close enough.

zipdogso

The wattage is wrong because a 12710 with a hotside of 27ºC only has Qcmax of 88w and a Qcmax of 95w at 50ºC. Both these values are full power with no-load and absolute 100% ideal conditions, not undervolted to 12v. Without looking it up the best you could hope for in a real-life situation at 12v is probably around 75w - 80w (dependant on hotside temp.) absolute tops, assuming A1 TIM and correct clamping pressures etc.

The current draw will vary, as TEC's are semiconductors Ohm's Law is not very accurate but good for ballpark figures I suppose. The 7.5 amps you calculated will be an average figure, in this case, with this TEC, powered to 12v it can easily vary either way by 0.5 amp or maybe a bit more, depending on the temp of the hotside and the delta T. It would be reasonable to assume 8 amps as the draw if you are trying to decide on a PSU. (Ideally 8 amps should be less than 75% of max power of PSU.) If you are thinking of running this from the standard wires in your PC PSU it is a little overpowered and will cause problems, the 12708 unit is the max for safely running in that case.

If your hotside is very hot the current draw will easily go above 8 amps but so long as you are water cooling the hotside you will be fine.

This is a dinky little TEC what are planning to put it on....