The document describes a practical temperature controller designed for industrial applications, utilizing an 8051 family microcontroller and a DS1621 temperature sensor to display temperatures from -55°C to +125°C. User-defined temperature settings are stored in non-volatile EEPROM, allowing for maximum and minimum temperature control through switches. The system includes a relay for load control and requires various hardware and software components, including a transformer, voltage regulator, and embedded C for programming.

1. [ ElectromechEngineeringServices,Nashik www.goelectromech.in
Fot thisprojectContact @ 9421390933]
PRACTICAL TEMPERATURE CONTROLLER
ABSTRACT:
This practical temperature controller controls the temperature of any device according to
its requirement for any industrial application. It also displays the temperature on an LCD
displays in the range of –55°C to +125°C. At the heart of the circuit is the microcontroller from
8051 family which controls all its functions. An IC DS1621 is used as temperature sensor. The
DS1621 Digital Thermometer and Thermostat provides 9-bit temperature readings, which
indicate the temperature of the device. User-defined temperature settings are stored in a
nonvolatile memory EEPROM through 8051 series microcontroller .Maximum and minimum
temperature settings are entered to the MC through a set of switches which are stored in the
EEPROM -24C02.Maximum and minimum setting are meant for allowing any hysteresis
necessary. Set button is used first and then the temperature setting by INC and then the enter
button. Similarly for the DEC button. A relay is driven from the MC through a transistor driver.
The contact of the relay is used for the load, shown as a lamp in the circuit. For high power
heater load a contactor may be used, the coil of which is operated by the relay contacts in place
of the lamp as shown.
Standard power supply of 12 volt DC and 5 volt through a regulator are made from a step
down transformer along with a bridge rectifier and filter capacitor.

2. [ ElectromechEngineeringServices,Nashik www.goelectromech.in
Fot thisprojectContact @ 9421390933]
Block diagram
Hardware requirement Software requirement
1. Transformer. Keil compiler
2. Voltage regulator. Embedded C
3. Diodes
4. Capacitor.
5. Resistors.
6. Microcontroller (AT89S52).
7. Temperature sensor (DS1621).
8. BC547.
9. Relay.
10. Lamp.

3. [ ElectromechEngineeringServices,Nashik www.goelectromech.in
Fot thisprojectContact @ 9421390933]
11. LCD(16x2).
Keywords-
Leading project maker in Nashik, Electrical project in nashik goelectromeh.in, Electronic
project in nashik goelectromeh.in, computer project in nashik, Electrical project engineering
project in nashik goelectromeh.in, Electronic project engineering project in nashik
goelectromeh.in, Computer project engineering project in nashik goelectromeh.in,
Electrical project Diploma project in nashik goelectromeh.in, Electronic project Diploma
project in nashik goelectromeh.in, Computer project Diploma project in nashik
goelectromeh.in.