Detect 240V with a PIC

[mackrackit]

mackrackit, I have a glass of water here that i was using to test the water sensor.

For an electrical fire ?

skimask, The problem with 50Hz or any oscillating input is that the PIC detects multiple inputs. Im sure its easy enough to program around that but ive not got that far yet

Rectifiers do not care...do they?

[The Master]

That was a joke by the way! I probs should get a fire extinguisher though with some of the things i do.

My point with 50Hz is that the PIC thinks the smoke machine is ready then not ready 100 times a second. Ive been thinking about the code for that and it should be really easy. Just a variable that counts down to 0 from whatever value (i havnt worked that out yet). If it gets to 0 then there is no power, otherwise the input will turn on again before it reaches 0 and reset the variable to its start value

[skimask]

My point with 50Hz is that the PIC thinks the smoke machine is ready then not ready 100 times a second.

Ahh...
But what if there was a capacitor across that PIC and ground along with a high-ish value resistor to bleed that charge off the capacitor?
Anything click yet?

[mackrackit]

That was a joke by the way! I probs should get a fire extinguisher though with some of the things i do.

And safety glasses. I always wear them when I write code.

My point with 50Hz is that the PIC thinks the smoke machine is ready then not ready 100 times a second. Ive been thinking about the code for that and it should be really easy. Just a variable that counts down to 0 from whatever value (i havnt worked that out yet). If it gets to 0 then there is no power, otherwise the input will turn on again before it reaches 0 and reset the variable to its start value

As skimask said

You'll probably have to put a diode inline with the PIC pin and maybe a small R/C network behind that to filter out the 50hz half-wave and get a decent reading at the PIC

Should not be a problem.