Ever wondered how your Air Conditioner or Heater or Refrigerator adjusts its temperature automatically? The answer is a Temperature Control System. This article will show you how to build a model of such temperature control system using minimum components and without any complex circuit.

Automatic temperature control system is an important application used in almost all modern gadgets and smart homes. The system for controlling temperature automatically is achieved by using Arduino Uno-based microcontroller system. Arduino Uno due to its increased popularity finds its varied range of applications. Temperature sensor LM35 and Arduino Uno are the hardware used interfaced with computer, and the temperature is controlled in the room. Temperature is displayed on LCD display employing A1 pin of hardware with the help of analog pin utilizing pulse width modulation (PWM). We have designed temperature control as an automatic system that has been not attempted before the way it has been implemented.

Temperature Control Machine

Temperature control is a process in which change of temperature of a space (and objects collectively there within), or of a substance, is measured or otherwise detected, and the passage of heat energy into or out of the space or substance is adjusted to achieve a desired temperature.

The purpose of a temperature control system is to maintain a device at a constant temperature. Two types of actuators are commonly used to precisely control the temperature of optics, lasers, biological samples, or other temperature sensitive devices. One is a thermoelectric, or Peltier device. The other is a resistive heater. A precision temperature controller uses a current or voltage source to drive power through these actuators based on feedback from a temperature sensor. The temperature sensors are typically thermistors, RTDs, or linear devices such as the LM335 or AD590. With these types of sensors, stabilities of 0.01°C to 0.001°C are commonly achievable. Less precise sensors – thermocouples – can also be used for stabilities of about 1°C. The design of the system dictates the stability. If the sensor, actuator, and device being stabilized are poorly connected, the best controller in the world can’t help. The following block diagram shows a very basic temperature control circuit. Each symbol is defined in the table below. Each section is described in detail below. Temperature Controllers vary widely in feature set and performance. This block diagram is a representative sample, meant to familiarize the users with terminology and basic elements, not an exhaustive evaluation of what is available on the market.

As the name implies, a temperature controller - often called a PID controller is an instrument used to control temperature. The temperature controller takes an input from a temperature sensor and has an output that is connected to a control element such as a heater or fan.