Stir Plate HELP ME ha

I have everything I need but I haven't figured out if I can use these dc adapters or not.







And the only other thing Im concerned about is the colors of the wires on my computer fan, they are all the same. Heres a link to that...

http://www.amazon.com/gp/product/B00066ISVG/?tag=skimlinks_replacement-20

The colored wires in that picture are connected to the speed controller, the clear ones are the ones connected to the power.

Thanks in advance,
Chris

Might need a little more info! are you making a stir plate?

my power for mine is ericsson output 9v 300mA
input 120v ac 60Hz

"This adaptor can be anywhere from 9 to 12 volts DC, capable of delivering at least 200 mA continuously. The stir plates I build draw about 100 mA. The current requirements of other fan motors may be larger, but 200 mA should do. "

straight from how to page

so roku is 5v I would use the bottom one
and the fan looks like the same as used by stir starter

Looks like your fan is a 12 volt fan so you probably want a 12 volt supply. Are you going to implement any kind of speed control?

Even if the wires rant color coded they should still be in the connector in a standardized order

@bragona71 appreciate it!

Im not using an on/off switch, is that going to cause any issues. I figured it would just be on when its plugged in, and off when its not.

without a rheostat I'm not sure how you'd get the stir bar going. If your power output is great enough you might have problems throwing the stir bar

Wouldn't a $5 PWM controller from amazon work a LOT better than a rheostat, from a torque perspective? Hope so, cuz I ordered one for my build

I have a drawer full of "wall warts", and a bit of experimentation resulted in settling on 9 volts to provide the proper speed for my 12 volt computer fan and a short stir bar. Lower voltages don't have enough power in wort in my flask, and higher voltages end up throwing the stir bar. In plain water, I was using 4.5 or 5 volts, but once I started stirring a starter, I had to bump the voltage up due to the increased load.

Each system is going to be different, and I didn't want a variable resistance speed control, they aren't very efficient, and the more you turn them down the less efficient they become. The ideal speed control is a pulse width modulator circuit.

I found that the two wires, red and black, on my fan are not reversible, but reversing them does not harm the fan. On some of the wall wart wiring, the marked lead is +, and on others it's - The standard for DC wiring is black = ground. The standard for AC wiring is Black = Hot, White = Neutral. Ground and Neutral are two different things, but unfortunately more and more we are seeing white as ground as household electricians seem incapable of understanding that AC and DC are two entirely different systems with different color coding. Needless to say black as positive is an total violation of the age old color code standard for DC that goes back before AC existed, but we are starting to encounter that. This creates a situation where you don't dare assume anything!!

H.W.

nice work

Appreciate it @bragona71