The term “heat” refers to a form of energy in a system as a result of the increase in temperature (degree of hotness or coldness of the body) of the is also the measure of the total kinetic energy of a particular body which is measured joules (J) or kilojoules (kJ). It can be transferred from one body of higher temperature to a lower temperature in three ways which include (conduction, convention, and radiation) and in most cases through direct burning. (www.wikipiedia).

In our environment today, heat and temperature plays a major role in the biological, chemical, electronics, and mechanical activities of a living organisms and an electronic has been observed that a rise in temperature which leads to increase of heat could either facilitate the working efficiency of a system or resulting in damaging effects such as system break down of overload. Hence it was important to develop system and device such as thermometer, temperature scanner, heat sensor to help check on the temperature and heat level within the system in order to avoid any damage and optimize efficiency of the system.

The temperature sensor is often used in providing input to those control systems. However, in the case of too much exposure of some electronic component to extreme temperature, there will be an advance effect on them which can lead to the damage of the components. Most temperature monitoring devices are designed to respond to a particular (critical) temperature level. Hence these are usually incorporated with different kinds of alarm and light indicator unit which are triggered when a system reaches an unacceptable temperature level. (Whether high or low). These temperature monitoring device work with temperature sensors, normally transducer, which generate an accurate voltage output that varied linearly with temperature. They are mainly use for monitoring industrial machines, electronic boilers, ovens and other heat energy activities and this can be done by ensuring the temperature sensor and its leads are at the same temperature at the object to be measured. This usually involved making a good mechanical and thermal output. If the temperature sensor to be used to measure temperature in liquid, the sensor can be mounted inside a sealed end metal tube and can then be clipped into a bottle or served into a threaded hole. Temperature sensor provide the input to these control systems when temperature limits are exceeded, action must be taken to protect the system. (DOWNIE and NEI.A, 2012)



Although heat and temperature is important for carrying out daily activity, it is also important to note that when the amount of heat generate by a body or system is not regulated it will lead to a damage and also face limitation which include the inability to be use in all fields of life. the problem of cost of manufacturing and maintenance also possess a by treat to the construction of the device.


The aim of the study is to examine the construction and application of heat sensor. And the objectives are;

  1. Thermistor and resistance was connected in series and make a potential divider circuit.
  2. The output voltage is applied to a NPN transistor a resistance
  3. Transistor conduct when base voltage is greater than emitter voltage.



The overall aim of the study is to analysis the effect of temperature and heat on our environment, interpret the finding, analyze the implication and develop a means of keeping a check on the level of temperature and heat with a system. The study will be of great benefit to not just the institution, student and also general public as it will help reduce the risk of fire out break and malfunction of the system. 

The information provided by the study will sense as an essential guideline for further study on the construction application of heat sensor and contribute to the existing literature on the construction and application heat sensor.


1.5     DEFINITION OF TERMS         

HEAT: This is the amount of energy play from our body of matter to another spontaneously due to their temperature difference. It is also the measure of the total kinetic energy of particular body.

SENSOR: A sensor is a device that detects and responds to some type of input from the physical environment.