Reverse polarity diode, Not stopping current.

[Tomer]

Hi All
This is probably very basic but i am missing something, so your help is appreciated a lot!

I am trying to use a 1N4001-G diode to act as a reverse polarity protection diode.
Placing the Diode on the + rail have no affect, no matter the direction of the Diode. result is the same my led is ON.

My understanding is that if i am placing the diode in reverse on the + rail, i should have no current flow.
Why my Led is on ?

Please see pictures in the link below:
https://photos.app.goo.gl/PMFafxxXAEkuYWDs1

Thank you
Tom

[bd139]

The diode is shorted there. The breadboard rail isn’t broken between both legs of the diode.

[Lee Leduc]

Looks like you're trying to build a circuit on the power bus. The diode is shorted and not part of the circuit.
Take a look at this short tutorial titled "How to Use a Breadboard and Build a LED Circuit"



https://computers.tutsplus.com/tutorials/how-to-use-a-breadboard-and-build-a-led-circuit--mac-54746

[Tomer]

Ohh men , I feel so dumb now.
Thanks guys for spotting the issue so quickly.

Tom

[Lee Leduc]

Don't worry about it. We've all made mistakes like this when we were learning to use breadboards. Think of it as a rite of passage!

You should see the burn marks on my breadboards when I've let the "magic smoke" out of a component!!

[Tomer]

Thank you for the encouragement !

[bd139]

Yeah don't sweat it - it happens

Only last week, after 30 years of doing this stuff, I burned my fingers on a diode because I accidentally connected it across the supply instead of in series with it