How to Convert Fluorescent Starter to Thermal Switch
Intro: How to Convert Fluorescent Starter to Thermal Switch
Fluorescent starter is essentially two bimetallic strips in a sealed glass capsule, with a small gap between them.
The principle of this experiment is Metal expansion and contraction .
Materials:
1- 12 volt CPU Fan.
2- 12 Volt supply.
3- Fluorescent starter.
4- Candle.
Steps:
1- Break the starter glass and try to not damage the metal inside (Take all safety precaution when you do that to avoid any injury).
2- Make sure that there is a small gap between two metal as shown in attached picture.
3- Connect the circuit as attached in the first circuit diagram and fix the starter about 2 cm above the candle.
When the candle lighted up ,the starter metal will expand and attached together , the fan will turn on and turn off the candle ,the two metal will de-attach and turn off the fan.
Note that CPU fan is a brush less dc motor and it will not cause spark in starting ,the spark can damage the metal and it will not work for long time ,so if you connect a load that take more current and cause a spark in the starter you can use transistor showed in the last diagram to avoid this issue .
if you find this tutorial useful to you , please vote for it in the Electronics Tips & Tricks contest.
Many thanks
Husham
13 Comments
marknluke 10 years ago
Husham Samir 10 years ago
astral_mage 10 years ago
ToXiCATOM 10 years ago
ynze 11 years ago
Husham Samir 11 years ago
DIVYA GARG 11 years ago
Husham Samir 11 years ago
if I am not using the transistor ,the circuit will work but a spark will happened every time the metal attached and it will damage the bimetallic strips ,so the purpose from the transistor to increase the life time of bimetallic strips.
Regards
Husham
iceng 11 years ago
A
Husham Samir 11 years ago
francisdsa 11 years ago
can you do a test and measure the temperature when it starts bending? so we can accordingly know when it switches at what temperatures..
Thanks
Husham Samir 11 years ago
I have tried your suggestion but unfortunately it is not efficient because the two metal is too small and not easy to twist them to get the required setting .
for a project like parked car cooler I suggest you to use LM35 temperature sensor with op-amp comparator .
rimar2000 11 years ago