Computer PSU's and Peltier elements?
Hey, I have 2 158W Peltier elements, that I would like to mount to some CPU-heatsinks, and power with an old 400W PSU.
Can I "just do that"? There seams to be some caveats with how these units draw power AFAIK.
Also, does anyone have any experience with how much heat displacement is needed to not just ending up frying the unit?
Any suggestions on what heatsink to pair them with, and how strong a resistor to put on them?
I want to use them at the maximum power I can get them to run with continuously for up to 2 hours.
I have way too limited experience with electronics, and only a week to build my project, so I kind of have to go with the simplest approach here :(
Can I "just do that"? There seams to be some caveats with how these units draw power AFAIK.
Also, does anyone have any experience with how much heat displacement is needed to not just ending up frying the unit?
Any suggestions on what heatsink to pair them with, and how strong a resistor to put on them?
I want to use them at the maximum power I can get them to run with continuously for up to 2 hours.
I have way too limited experience with electronics, and only a week to build my project, so I kind of have to go with the simplest approach here :(
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The higher the voltage, the more power will be transmitted from side A to side B.
The power (heat) showing up at side B will be the sum of the power transmitted from the A side plus the power input to the electrical connections.
In order not to fry the unit, you must:
a) not exceed the maximum junction voltage, specified by the documentation
b) not exceed the maximum junction delta T - you have to dissipate the heat from the hot side or it will cook itself.
A 146 watt peltier will draw 146 watts of power from one the electrical, and according to wikipedia are about 5-10% efficient. that means you'll get 10% , about 15 watts of cooling, so the hot side will see upwards of 160-200 watts of heat. Sufficiently cool the hot side and you'll be fine.
The power (heat) showing up at side B will be the sum of the power transmitted from the A side plus the power input to the electrical connections.
In order not to fry the unit, you must:
a) not exceed the maximum junction voltage, specified by the documentation
b) not exceed the maximum junction delta T - you have to dissipate the heat from the hot side or it will cook itself.
A 146 watt peltier will draw 146 watts of power from one the electrical, and according to wikipedia are about 5-10% efficient. that means you'll get 10% , about 15 watts of cooling, so the hot side will see upwards of 160-200 watts of heat. Sufficiently cool the hot side and you'll be fine.
So basically just any modern CPU heatsink should do, if I just limit the voltage/highen de resistance? It's a 12V Unit, and the PSU has a 12V output, but it doesn't say if I can draw that many amps from one outlet on the unit...
You don't need a series resistor. the peltier itself has an internal resistance that acts as a current limiter, so long as the voltage is in the appropriate range.
Don't use pwm to vary the power, because peltiers, despite being solid state, don't really like being switched on and off rapidly.
Don't use pwm to vary the power, because peltiers, despite being solid state, don't really like being switched on and off rapidly.
So chances are, with one peltier, hooking the peltier to one of the 12V outputs, and the heatsink fan to another, should be adequate to get stable performance?
What *exactly* are you trying to do?
Yes, hooking the wires up to suitable voltage and heatsinking the hot side it will get cold on the other side -- 'stable performance'...please tell me you're not using it to cool a CPU. These days there's no good reasons to take the risk of condensation on your pc when other cooling solutions will do.
Yes, hooking the wires up to suitable voltage and heatsinking the hot side it will get cold on the other side -- 'stable performance'...please tell me you're not using it to cool a CPU. These days there's no good reasons to take the risk of condensation on your pc when other cooling solutions will do.
Of course not, I am trying to make a 'cold serving plate' for instant freezing and serving icecream.
May 3, 2011. 9:28 PMblawrence1
says:
I hope you received your reply earlier and checking the date, April 1st, I'm hoping you're pulling our leg.
A peltier is only capable of cooling a maximum of 40 degrees farenhiet below the room temperature on the heat sink on the hot side of the device. You'll be serving cool melted ice cream at best.
A peltier is only capable of cooling a maximum of 40 degrees farenhiet below the room temperature on the heat sink on the hot side of the device. You'll be serving cool melted ice cream at best.
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