Richard, ante is correct in his comments to you. Current is the same throughout a series circuit, so your fan is not going to get enough current to run when it must first go through the LED.
You want a LED connected to a resistor to ground. If you have a 2 volt drop through the LED, then you calculate your current limiting resistor for 10V/R = LED current. (This is from 12V - 2 V)
Probably something around 2K2 will work. Depends on the LED. Check your datasheet to be sure. Also note that your circuit current consumption is the consumption of the fan plus the current for the LEDs to ground. You did not mention the current available from the transformer or the consumption of the fan, so I thought I should mention it.
MP
MP
You want a LED connected to a resistor to ground. If you have a 2 volt drop through the LED, then you calculate your current limiting resistor for 10V/R = LED current. (This is from 12V - 2 V)
Probably something around 2K2 will work. Depends on the LED. Check your datasheet to be sure. Also note that your circuit current consumption is the consumption of the fan plus the current for the LEDs to ground. You did not mention the current available from the transformer or the consumption of the fan, so I thought I should mention it.
MP
MP
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