I've been trying to find info on the web about this. I thought I understood well enough, but I must still be doing something wrong.
I'm working with 12vdc and 24vdc power. At one point I need to step down the 24vdc to 12 to operate a relay (so very small amp draw) since I don't happen to have 24v relays on hand. I also need to step down 12vdc 1.0amp to 3.3 to 4 volts to power an led.
Most recommendations for LED applications (anecdotal ones) recommend a simple series resistor. 250ohm for instance to get 12vdc down to 3 to run an led. I don't get anywhere near this. And using a resistor doesn't seem to allow any amps through at all. What am I doing wrong? (as you can see i have a very limited skill with electronics)
Another instance, I found that a 70K series resister will bring the 24vdc down to 12vdc, but again, there is absolutely no amperage present at the 12vdc point with my meter. I hook up a fan or a light and there is nothing! How is this possible when the meter reads 12v?
I'm really confused here because there are dozens and dozens of web pages out there describing how to step down low draw low voltage for things like LEDs using series resistors.
I attempted a voltage splitter as well. Two or three resistors in series and the voltage varies depending on where you tap it. But again, no current seems to be available to actually run anything. (i'm really getting frustrated here).
I suspected that it might have something to do with the fact that I'm using SMPS transformers, but I tried a conventional 12vdc wall transformer and the very same thing happened.
Any help at all? Thank you so much!
I'm working with 12vdc and 24vdc power. At one point I need to step down the 24vdc to 12 to operate a relay (so very small amp draw) since I don't happen to have 24v relays on hand. I also need to step down 12vdc 1.0amp to 3.3 to 4 volts to power an led.
Most recommendations for LED applications (anecdotal ones) recommend a simple series resistor. 250ohm for instance to get 12vdc down to 3 to run an led. I don't get anywhere near this. And using a resistor doesn't seem to allow any amps through at all. What am I doing wrong? (as you can see i have a very limited skill with electronics)
Another instance, I found that a 70K series resister will bring the 24vdc down to 12vdc, but again, there is absolutely no amperage present at the 12vdc point with my meter. I hook up a fan or a light and there is nothing! How is this possible when the meter reads 12v?
I'm really confused here because there are dozens and dozens of web pages out there describing how to step down low draw low voltage for things like LEDs using series resistors.
I attempted a voltage splitter as well. Two or three resistors in series and the voltage varies depending on where you tap it. But again, no current seems to be available to actually run anything. (i'm really getting frustrated here).
I suspected that it might have something to do with the fact that I'm using SMPS transformers, but I tried a conventional 12vdc wall transformer and the very same thing happened.
Any help at all? Thank you so much!