I have gone through many of online blogs and websites for guidelines about selecting Peltiers but somehow I am still lost in the middle. I am still missing major numbers to be able to select which peltier to use.

So, here is my application in case someone can guide me in detailed way about calculations. Thanks in advance.

I have glass slide 25*75 mm with thickness 1.1 mm, and above this glass will be some biological sample. The whole experiment starts at room temperature ~27 c. At some point later, the temperature above this glass slide will increase to around 60 C in a matter of 10 seconds and I need to maintain it back to around 37 c (suitable temp for bio samples to survive). I will need to maintain this temperature for around 5 minutes.

So, to select Peltier I need to know my heat load ... and also heat that will be generated by peltier itself to cool down my sample.

Can someone guide me into that ,,, I know more or less the data sheets and I will need heat sink and fan but cant do full calculations to come to the point to choose a peltier.

Thank you in advance.

  • 1
    \$\begingroup\$ What's making the sample go to 60 C? How much heat is this providing? What is the thermal mass of the sample (is it cells, so something like water 10um x 20 mm dia?) Where's the coverslip ? How are you illuminating - epi or trans ? Is there a hole in your cooler? \$\endgroup\$ – D Duck Feb 8 at 11:20
  • \$\begingroup\$ Peltiers are not transparent. Do you need to see through this glass slide during operation, perhaps with a microscope? If so, consider using low heat light sources instead. Otherwise you're looking at cooling air with the Peltier and guiding it over the slide. \$\endgroup\$ – user_1818839 Feb 8 at 12:13
  • \$\begingroup\$ @DDuck .... I apply some voltage to electrodes inside chamber and this is the reason it heats up. These are cells networked in tissue sample i.e. 25*25 mm2 and thickness is 5 microns. Cover slip is closing chamber from top of polymer chamber which is below 100 microns high. I illuminate epi. No hole, to homogenize the requested cooling later. Hopefully it helps. \$\endgroup\$ – MzD Feb 8 at 14:39
  • \$\begingroup\$ @BrianDrummond... Yes I know that. I look from top inside a closed chamber with cover slip from top. \$\endgroup\$ – MzD Feb 8 at 14:41
  • \$\begingroup\$ @DDuck .... how much heat ir provides ? to be honest, I dont know how to reply in exact numbers...like in Q (W) as in peltier guidelines. It just heats up from 27 to 60 c, so the volt I apply provides around +30 C heating. \$\endgroup\$ – MzD Feb 8 at 14:43

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