Report on Arduino Based Temperature Controller Bath

INTRODUCTION
This system is ideal for constant temperature applications in refractrometry, polarimetry, rotational viscometry, in biotechnology laboratory for development of culture applications and general laboratory work and also for the critical applications requiring a high degree of temperature accuracy and uniformity. Constant temperature baths are provided with Arduino based controller for uninterrupted long run usage & safety. This water bath have seamless tank and provide high control accuracy as well as uniformity. Our temperature bath provides exceptional temperature control at temperatures 70-100oC. Heating unit rapidly heat the bath medium to any temperature within the bath range. The unit is equipped with several insulations like glass wool, wooden insulation, thermocoal. Our bath is made of stainless steel corrosion free material. The insulated bath offers quick-set temperature control. Arduino controlled temperature regulation, temperature monitoring make this bath an attractive and fully functional addition to the modern laboratory. The display in the circuit indicates temperature in Celsius or Fahrenheit.

1.2 OBJECTIVE OF THE PROJECT
The final year mini project aims at exposing the students undergoing higher technical studies to the thoughts and logic that must be developed to ensure that one is able to integrate his/her ideas into something concrete. This generally is initiated by the inception of an idea or concept, which not only aims at developing a project (hardware or software), but also the in depth study of the earlier existing products in same category and their deficiencies. Accordingly an approach is taken to propose a solution, which is better from the previous ones in one respect or the other. With the same approach in mind, we, the final year students of bachelor of technology (electrical and electronics), have taken up the mini project name “ARDUINO BASED TEMPERATURE CONTROLLER BATH” as our final year mini project.

1.3 SCOPE OF THE PROJECT
The temperature capability of bath can be increased by using the high range sensor rating heaters .With the efficient heaters the time requirement of heating can be decreased and find good application in Refractometry, Polarimetry, Rotational Viscometry, in biotechnology laboratory for development of culture applications and general laboratory work. Ideal for critical applications requiring a high degree of temperature accuracy and uniformity.

DESIGN OF THE BATH

2.1 CAPACITY
The size of the bath is 20*30*10 cms and it is capable of carrying three and half litres of liquid. The volume of the bath used in this project is 6000 cubic mts. As the size of the bath increases the cost also increases. The size of the bath varies from one application to another. Different Liquids can be heated in this bath as per the application. Insulation is provided around the bath in order to increase the efficiency of heating. The increase in the size of the bath also increases the insulation for the bath.

2.2 MATERIAL OF THE BATH

2.2.1 Material properties:
Among the materials that withstand corrosion, stainless steel shows an excellent resistance in a large number of atmospheres, due to a phenomenon known as passivity. Stainless Steel is protected from its environment by the formation of a very thin passive film or passive layer. It is strongly bonded to the surface, which prevents further direct contact between the metal and its more or less aggressive environment metal. The Steel also provides good life time and flexibility while using. Physical and mechanical properties (toughness, strength and ductility), ease of fabrication (particularly ease of forming Among the materials that withstand corrosion, stainless steel shows an excellent resistance in a large number of atmospheres, due to a phenomenon known as passivity. Stainless Steel is protected from its environment by the formation of a very thin passive film or passive layer. It is strongly bonded to the surface, which prevents further direct contact between the metal and its more or less aggressive environment.

In Stainless Steel, the passive film also has the advantag1e, compared, for example, to a paint layer, being self-healing. Chemical or mechanical damage to the passive film will heal or repassivate in oxidising environments. The material used for bath is Stainless Steel. It is less weight, corrosion free and efficient heat transfer) excellent fatigue resistance and energy absorption capability are some of the properties of Stainless Steel which enable the specific requirements of structural components to be met.

2.2.2 Choice of material:
“STAINLESS” steel contains a great number of variants , all with atleast 12% chromium(Cr) and mostly also other alloying elements, nickel(Ni) and molybdenum(Mo) being the most important. This extensive field has been divided for fasteners into 3MATERIALGROUPS based on their metallurgical structure

The martensitic and ferritic groups are hardly of any importance “STAINLESS” steel contains a great number of variants, all with atleast 12% chromium(Cr) and mostly also other alloying elements, nickel(Ni) and molybdenum(Mo) being the most important . This extensive field has been divided for fasteners into 3MATERIALGROUPS based on their metallurgical structure:

The martensitic and ferritic groups are hardly of any importance. And addition of molybdenum. Better resistance to aggressive media such as sea climate(chlorides), industrial atmosphere(sulphurdioxide), oxidizing acid sand there where pitting may occur. Unless otherwise specified fasteners from austenitic stainless steel shall be clean and bright. For maximum corrosion resistance passivation is recommended.

2.2.3 Performance of steel under different corrosion:
Atmospheric (Chemical) Corrosion:
This kind of general corrosion is caused by chemical attack from the atmosphere or aggressive media and is mostly defined as the loss of surface material in μm/year. The attack passes evenly and gradually, mostly visibly and it is checkable. Sudden collapse does not occur, so this type of corrosion is not dangerous. Generally gradeA2 is very satisfactory, but under more aggressive conditions A4 is recommended.

Contact (Galvanic) Corrosion:

When two metals in the presence of an electrolyte create a difference of electrical potential, a galvanic action occurs which causes the lesser noble metal (anode) to corrode and to sacrifice itself, protecting the noble metal (cathode). The higher the difference in electrical potentials and the larger the contacting area of the noble metal relative to that of the lesser noble, the more severely this contact corrosion will attack the anode. Passive austenitic stainless steel is relatively noble, where as fasteners generally have a comparatively small surface in relation to the construction. Aluminium performs very well, as practice has proven, because of the formation of an insulating layer of aluminiumoxide. Steel and cast iron have to be covered with a closed protective layer e.g. zinc or lacquer. Copper and brass are applicable, when the fasteners are relatively small. Generally this combination can only be advised when an adequate insulation is applied. Dry wood will not cause problems. Insocked condition pitting corrosion may occur on the longrun, however the time of resistance is much longer than with plated steel. Plastic performs well, although deformation of washers, for example, may cause crevice corrosion.