Connecting arduino to the display of a washing machine?

[Cliff Karlsson]

I am trying to figure out how to connect an arduino to my washing machines display. The display has several leds that light up under the program.

If I measure the leds they draw 1v when they are on. Can I connect the positive
end of the leds with a wire directly to the input of the arduino?

Do I also need to find neutral or ground from the washing machine?
And how sensitive are smd leds when soldering?

The leds are the component marked DLxx

[TheoL]

Not an eletronics expert. But I think I would use an opto coupler between the arduino pin and the led of the washing machine. Better safe than sorry.

[ahmedadelhosni]

Using optocoupler to isolate both circuits is better.

I really like the idea of the LED. Actually I was thinking of using a pizeo electric or any device to detect the vibration when it stops for an interval amount of time. but the LED solution is better.

[Cliff Karlsson]

Well I have got second thoughts on the project after asking the same question in an electronics forum. And they recomennded me not to try anything without better electronics knowledge.

As there are 230V mains also on the same board they mentioned something about commond ground witch could cause 230V to get sent to the arduino and could be very dangerous. Well I must admit my electrics knowledge is sub-basic so it might not be such a good idea afterall.

[hek]

@Cliff-Karlsson

Yep, better safe than sorry.

[flopp]

Maybe you can use LDR, one for each LED but make good isolation when you put the LDR close to the LED.

With LDRs you will not use same power and "almost" no chance that you get any shortcut between Arduino stuff and washing machine