Model Boat Mayhem

Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: Ian K on May 30, 2015, 05:19:56 pm

Title: Elektrickery help!!
Post by: Ian K on May 30, 2015, 05:19:56 pm
Hi,

Do any of you guys know how I could drop a 14.8 volt lipo supply, down to 12 volts for a pc cooling fan.

I am running other things from the lipo at the standard voltage, I just need to reduce down a separate circuit for the 12 volt fan.
Electronics is not something I am very knowledgeable about :embarrassed:

Maybe a variable pot or a fixed rating resistor? I would prefer a variable pot, to reduce/increase air flow speed. I just don't know what rating to use, as it all seems mumbo jumbo to me......sorry!

Thanks in advance

Ian
Title: Re: Elektrickery help!!
Post by: inertia on May 30, 2015, 05:29:15 pm
Ian
Knock yerself out, m'duck! http://www.hobbytronics.co.uk/voltage-regulator-l7812 (http://www.hobbytronics.co.uk/voltage-regulator-l7812) The circuit is on the Datasheet.
Dave M
Title: Re: Elektrickery help!!
Post by: Netleyned on May 30, 2015, 05:31:22 pm
Try it at the stated voltage.
Using a resistor fixed or variable will introduce more heat.
I am assuming the cooling fan is to cool.
A cheapo esc, forward only and small current rating
would give you control of the fan speed and therefore
cooling


Or do as DM has posted  :-)) :-))


Ned


Ned

Title: Re: Elektrickery help!!
Post by: inertia on May 30, 2015, 05:32:37 pm
Then there's this.... https://www.youtube.com/watch?v=IjJWWGPjc-w (https://www.youtube.com/watch?v=IjJWWGPjc-w)
DM
Title: Re: Elektrickery help!!
Post by: Umi_Ryuzuki on May 30, 2015, 05:57:11 pm
Something like the Dimension Engineering voltage regulators would work.
They are specified as "switching" regulators, and don't dump the excess voltage as heat, as far as I can tell.


https://www.dimensionengineering.com/products/de-swadj


 :-)
Title: Re: Elektrickery help!!
Post by: Ian K on May 30, 2015, 07:51:40 pm
Hi,

Thanks for all the input so far chaps. The fan is used as a positive pressure blower unit, for a home built smoke generator.
The 14.8 volt lipo, supplies the power to the twin heating coils.

I just need to tweak the brush less PC fan speed, to get a varying flow of smoke.

Ian