what transformer to make this little fan run?

[Romano]

Hi guys I want to connect this little friend to a 12V transformer (if that's the name of it) but I had a bad experience the other day trying to do the same with a led strips, even when the transformer was 12V I believe the Amps were too high because it instantly killed the led strips a friend of mine told me those transformers has the Volts and Amps and maybe the one I used was too many amps for the 12V led strip which ended in a dead led strip, I have some transformers of different volts and amps, I would like to know which one is safe to make this little fan run, also what's the green cable for?

 

Thanks

 

[StackUnderflow]

I don't think there is "too much amps" in EE. The current (amps) is determined by the voltage and load (impedance). The load is determined by what you connect to your power source. The power source can provide a max power, which is the product of voltage and current. Since the voltage is set in most cases, the power supply has a maximum output of current. In other words, you can go above the max current of your PSU, and your setup will fry, but you can't "provide" too much current.

[Romano]

I don't think there is "too much amps" in EE. The current (amps) is determined by the voltage and load (impedance). The load is determined by what you connect to your power source. The power source can provide a max power, which is the product of voltage and current. Since the voltage is set in most cases, the power supply has a maximum output of current. In other words, you can go above the max current of your PSU, and your setup will fry, but you can't "provide" too much current.

 

Hi, its to connect the fan directly to one of these! 

[StackUnderflow]

Hi, its to connect the fan directly to one of these! 

 

My point is, if you connected the powerwires backwards for the LED strip, or the voltage provided by the PSU is above what is rated for the LEDs, the LEDs can burn out.

 

Read here regarding the 3 pin fan layout: http://pcbheaven.com/wikipages/How_PC_Fans_Work/. In short, the 3rd pin tells the Mobo how fast the fan is spinning, so I wouldn't worry about it.

 

I don't think DC motors have a polarity, but if there's a controller attached to that motor (most PC fans don't (I think) have them, unless they are brushless) there is a polarity concern (just connect black to ground and hot to red). I would try 5V first, and if the fan doesn't spin, try 12V. Modern day PC fans are 12V, but that doesn't look like a standard PC fan.

 

Just read the voltage ratings on the power supply and you should be fine. 12V even at 1 amp would most likely not hurt you. 

[W-L]

Hi, its to connect the fan directly to one of these! -PIC-

 

You must make sure the 12V power brick but make sure it's a regulated 12V, where the output is exactly close to if not exactly 12V, regular old power bricks with no regulation usually output a voltage >12V something between 15-18V where under load it will drop to approx above 12V. LED strips only take as much current as they need and aren't like single doides that need current limiting, the power brick you have in your photo looks to be an unregulated one. 

[Romano]

My point is, if you connected the powerwires backwards for the LED strip, or the voltage provided by the PSU is above what is rated for the LEDs, the LEDs can burn out.

 

Read here regarding the 3 pin fan layout: http://pcbheaven.com/wikipages/How_PC_Fans_Work/. In short, the 3rd pin tells the Mobo how fast the fan is spinning, so I wouldn't worry about it.

 

I don't think DC motors have a polarity, but if there's a controller attached to that motor (most PC fans don't (I think) have them, unless they are brushless) there is a polarity concern (just connect black to ground and hot to red). I would try 5V first, and if the fan doesn't spin, try 12V. Modern day PC fans are 12V, but that doesn't look like a standard PC fan.

 

Just read the voltage ratings on the power supply and you should be fine. 12V even at 1 amp would most likely not hurt you. 

 

 

You must make sure the 12V power brick but make sure it's a regulated 12V, where the output is exactly close to if not exactly 12V, regular old power bricks with no regulation usually output a voltage >12V something between 15-18V where under load it will drop to approx above 12V. LED strips only take as much current as they need and aren't like single doides that need current limiting, the power brick you have in your photo looks to be an unregulated one. 

 

Thank you guys! I will try first with the lowest one, the powerbricks I own they don't have regulation, so I will try with the lowest first, I hope the fan doesnt burn out, if it does atleast is not a new one right?

[W-L]

Thank you guys! I will try first with the lowest one, the powerbricks I own they don't have regulation, so I will try with the lowest first, I hope the fan doesnt burn out, if it does atleast is not a new one right?

 

I don't recommend to run without a regulated supply since the incoming AC voltage if not stable which will always vary, affects the DC output side. I've done it before on a a set of LED's where I picked up an unregulated one and it burnt in the LED's after a few months.