PHYS1630: Thermal Control Systems
Lab #3: Thermoelectric (Peltier) Modules (2018F)

Introduction

In this lab you will measure the characteristics of a Peltier effect thermoelectric cooler.

Equipment

Heatsink with TEC
The heatsink with thermoelectric cooler and resistor mounted on top. The resistor dissipated heat which acts as a load for the TEC cooler. For this experiment connect a jumper lead to each resistor terminal and run to a 25V/1A power supply (as per lab #1) and run wires from the CP60333 TEC module to a 2A power supply.

TEC Setup
The setup as wired for the lab. The large supply on the far right powers the TEC module (set it for a constant current of 2A) and the smaller supply powers the resistor which acts as a load for the TEC cooler.

The Experiment

FIRST, measure the ambient temperature of the heatsink and the resistor. Refer back to your notes from lab #1 since the heatsink and the resistor are the same type and so emissivity will be the same. Mount the heatsink flat against an insulating surface (in the same manner as lab #1) so the thermal resistance will be known.

SECOND, power the TEC with a current of 2A. Allow the temperature of the resistor and heatsink to both stabilize then measure each as well as the exact current and voltage of the TEC. With no current through the load resistor this temperature increase will be due solely to the dissipation of power created by the TEC itself.

THIRD, with the TEC still operating drive the resistor to a current of 0.447A so that a load power of 10W is created. Allow the temperature to stabilize again and measure both the resistor and heatsink temperature.

FOURTH, turn the resistor off but leave the TEC powered. Add a fan (in the same manner as lab #1) to decrease the thermal resistance.

FIFTH, when the temperature has stabilized measure both again.

SIXTH, power the resistor to dissipate 10W again and measure the temperatures again once they have stabilized.

Lab Report

For this experiment, an abbreviated lab report is required (word processed, never hand-written) with the same format as PHTN1300. Answer each question in the form "4a., 4b., 4c. ..." with each new question (#4, #5, etc) beginning on a new page. Do NOT answer an entire question (e.g. question 4) as a single paragraph without identification of sub-parts ('a', 'b', etc). Submit the lab report in a bound folder NOT simply a pile of loose, stapled papers nor a thick binder!

Each student must submit a unique lab report - no portion other than the results must be shared between lab group members. For all calculations show the formula used and all substituted values (i.e. show your work, not just the final value). If a value is used from a previous lab, state this.

  1. Calculate the expected temperature of the heatsink ALONE with a 10W load and no TEC for comparison (i.e. the resistor mounted directly on the heatsink). This was done already in lab #1 so repeat it here. As usual show all calculations an all sustituted values.
  2. Calculate the expected temperature of the heatsink with a 0W heat load (the resistor is unpowered) and the TEC powered to 2A of current. Again show all work.
  3. Calculate the expected temperature of the COLD side with a 0W heat load and the TEC powered to 2A of current. To do this, find the ΔT from device specification graphs of the device.
  4. Calculate the expected temperature of the heatsink with a 10W heat load and the TEC powered to 2A of current.
  5. Calculate the expected temperature of the COLD side with a 10W heat load and the TEC powered to 2A of current. To do this, find the ΔT from graphs of the device.
  6. Repeat the previous four calculations with the much lower thermal resistance of the heatsink when fan cooled (use the value of thermal resistance again from lab #1 - be sure to state this value).
  7. Make a table summarizing predicted and observed results from this experiment. There are four temperatures predicted and four temperatures observed.