How do I connect Float switch with LED

[mche1997]

I want to fit a float switch and a LED to a water reservoir tank to my car. So when the water level in the tank is low, the LED flashes to warn me. It is just the cheap float switch you see on ebay with 2 yellow wires and a LED with a resistor. Do I need a circuit board for this ?

Any help will be appreciated

 

[Tony Stewart]

No just 14V with a 2V drop for a REd LED then 12 mA or less with 1k or more in series.
Reverse signal diode across LED to protect LED , which is rated for -5Vmax.
Float should be normally Open, in series , otherwise it has to short out LED.

 

[mche1997]

Thank you Tony, I'm not good at electronics or understanding, would you able to send me a simple drawing or diagram ? Theres already a resistor connected to the LED.

Many thanks

 

[Tony Stewart]

Simply switch ground to the negative or cathode side of the LeD with the low water sensor closed contact and connect 12V from fuse panel or dash power to LED + or Anode.


12V.....+++ LED (red?) ------(blk?) ........../switch NOrmally open/.... Ground....

 

[mche1997]

Hi Tony, thanks again.
OK, I connected the NEG from the LED to closed contact wire from float switch and the POS from LED connects to a POS power source from dash, there's another wire from the float switch, where do I connect that to ?

 

[Tony Stewart]

Gnd as I indicated before.

 

[mche1997]

Great, thanks a lot Tony