Temperature Control for Incubator

This is a project to make a working prototype of baby incubator in miniature scale. It will keep the warm temperature based on settings defined by user/operator (minimum & maximum temperature) . The same concept can be applied to other similar project, such as room controlled temperature etc.

The main part of this mini incubator:
1. Electric heater 12 V
2. Fan 12 V, to make air in/out from incubator
3. Temperature sensors, LM35/PTC/NTC/termocouple
4. Controller based on microcontroller AT89S51
5. ADC 8 channel, using 0809
6. Transistor/relay for controlling heater
6. LCD display 2x16, for user setting
7. Matrix keypad 4x3, for user setting



If temperature under the minimum threshold (set by user/operator), the controller will turn on the heater. It will keep heating until temperature reach the maximum threshold. If temperature above the maximum threshold, the controller will turn on the fan to make fresh cold air enter the incubator. And so on. The program done by assembly language.

Schematic download:
http://prasimax.googlepages.com/incubator_sch.jpg
Source code download:
http://prasimax.googlepages.com/incubator.asm
(note: you may need to change formula in program acoording to your sensor calibration)