Peltier Cooler: Working Principle & Applications
What is a Peltier Cooler
A Peltier Module is an electronic component that helps to counter Thermal Issues in a Circuit. Many Circuit components might require a cool environment to operate, while others might need to maintain a certain temperature and not above or below it, to operate effectively. Here Heat Sinks and Cooler Fans might not work due to architecture, hence Peltier Modules comes to the rescue, by solving the problem at hand as well as maintaining the Architecture.
The Working Principle
There are two ceramic plates separated by semiconductor pellets, when current flows through the semiconductor pellet, one Plate dissipates heat and the other absorbs heat.
Peltier Modules operate on the principle of the Peltier Effect. This effect brings up a temperature difference by transferring heat between two junctions. The Principal application of the Peltier Module is Cooling, but this module can also be used for heating or maintaining a temperature.
HeatSink and Cooling
As we know that a Peltier cools one side and heats its other side, using appropriate heat sinks with Peltier becomes rather necessary. Due to excessive heat on one side of the Peltier, the module might melt or may get internally damaged, thus A heat sink will sap the heat from the Peltier surface and keep it functioning and undamaged.
In addition to the Heat Sink one can even use a cooling fan to keep the Peltier from overheating, cooling fans come in various sizes, if bigger cooling fans hinder your design, you can look up small cooling fans to maintain the structure of your project and keep it from being bulky.
Heat Sinks and Cooling Fans avoid the Peltier from Overheating and help keep the environment of your Hardware safe from adverse effects of Peltier Cooling.
Note on the Appropriate Power Supply to use with a Peltier.
A Peltier Chip Power Supply Depends on the Peltier Chip you are using. Based on the General Usage A Peltier Approximately consumes 60 watts of Power. Thus the Maximum Voltage you can supply based on this Rating is 15 Volts with a 6 Amp of current, thus using any power supply that can provide you the same can be used.
Things to keep in mind while using a Peltier.
When Selecting a Peltier Module for implementation in the project, it is very important to know what does the Datasheet of the Peltier in Hand says.
A Peltier Data sheet Normally consists of the following terms on the 1st page
1.Hot Side Temperature
3. Delta Tmax
It is important for the user to not exceed Imax and Vmax levels while operating the Module.
One should always Consult HB for moisture protection options
There is also a Failure rate and Life Expectancy of a Module that is specified in the datasheet which shall be noted to get insightful information about the module.
Avoid Peltier Damage:
The current and voltage rating of the Peltier should be kept at the maximum value but this value should not be exceeded as it might be the major reason for the Peltier being damaged.
Many people tend to increase the current through the Peltier to increase cooling which is justified but only to a certain extent. The current through Peltier is proportion to the Cooling, but the heat generated inside the module is proportional to the square of the current, so after a certain point of time, if the current increases too much, even if it is within the safety margin, the square relation may overpower the linear relation and the Peltier might get damaged.
Secondly, Applying mechanical pressure on the Peltier might develop fractures inside the module that may harm the Peltier’s Functioning.
Applications of Peltier
A cooling module like Peltier has numerous Applications as it can act as the backbone of many Electronic Processes.
- Mini Refrigerators: As a small Electronic Project, a Peltier can be used to make mini Refrigerators that can even make Ice.
- Ophthalmic Lasers: Inside Ophthalmic Lasers, Peltier is used to keeping the laser diodes below a certain temperature, and cool the Crystals.
- Night Vision Devices: To avoid image noise, image sensors are cooled using the Peltier
- Battery Cooling of Electric Cars: One can use Peltiers to Cool Li-IOn batteries of Electric Cars
- cryopreservation: We can use Peltier to preserve tissues, cells, and other similar substances in cool temperatures that are cooled using Peltiers