Pages: [1]   Go Down
Author Topic: Wire in external power and still control power?  (Read 313 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Newbie
*
Karma: 0
Posts: 2
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

I don't know if this is feasible, but I have a very small 40mm fan which is rated at 12 V/0.07 A, and the Arduino really can't run it with 5 volts. I plugged it into a 9 volt battery and the power worked great.

How would I go about adding around 9 volts for the fan while still letting the board control the power (this is a temperature control system for my BBQ smoker with thermistors. )


Thanks
Logged

Austin, TX
Offline Offline
Faraday Member
**
Karma: 64
Posts: 6055
Baldengineer
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

I don't know if this is feasible, but I have a very small 40mm fan which is rated at 12 V/0.07 A, and the Arduino really can't run it with 5 volts.
You need to look at voltage and current.  The fan needs 70mA at 12V. 

You'll need to use a transistor to connect it to an Arduino.  Some how I suspect others have done this.  (https://www.google.com/search?q=control+12v+fan+with+arduino)

I plugged it into a 9 volt battery and the power worked great.
FYI.  Those small 9V batteries are lousy at running motors (like fans).  It'll only last 4 or 5 hours if the fan draws 50mA (de-rating since you aren't running at 12V).  You'll want to use a AC to DC 9V supply.
Logged

Capacitor Expert By Day, Enginerd by night.  ||  Personal Blog: www.baldengineer.com  || Electronics Tutorials for Beginners:  www.addohms.com

Johannesburg UTC+2
Offline Offline
Faraday Member
**
Karma: 60
Posts: 3242
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

You'll want to use a AC to DC 9V supply.

My late father-in-law often mentioned a steam driven bbq spit design that he saw decades ago in a magazine (PM or similar I suppose). Alas he could never produce the design but was adamant that he had seen it, probably back in the 50s or so.

Since this is for a bbq, you could rig some kind of steam powered generator with the boiler tubes in the coals.....
Logged

Have you looked for answers in the Learning, Reference, Products and Playground tabs on http://arduino.cc/en/ ?
Look here http://electronicsclub.info/ for basic electronics

Pages: [1]   Go Up
Jump to: