Hi all, I've been lurking around these forums looking for help and searching through which has helped me out a lot :)
My background is basic electronics which I'm using to create a ROV which has bilge tanks to raise and lower it in the water. These bilge tanks are controlled with bilge pumps through motor controller; thats all working brilliantly. The whole thing is communicated with using an Ethernet shield and firing OSC commands down, with a PC in the way which then connects to an Xbox360 controller.
These bilge tanks are sealed, and I need to know the water level in them, at both ends (they are 1m long lengths of 110mm diameter drain pipes). I have acrylic rods which I intend to connect a nichrome wire loop to which - as far as I understand - is a length of wire with a known resistance per cm/m/inch whatever.
The nichrome wire I have is 42SWG (1Ohm per CM), and I'm hoping to connect 5V from the Arduino at the top, and then another lead to an AnalogIn pin and measure the voltage, with the hope that as the water goes up the acrylic rod the resistance of the loop will change as the water will create a short.
First, does any of this make sense (smartest way of doing it?) and is my Arduino going to suddenly blow up if I were to just connect the 5V through the nichrome wire to the GND on the board itself? I'm worried as to whether the nichrome takes as much current as possible and burn out the board, or if it will only use what its given (40ma?).
I typed this quick at lunch, but I'll be able to post a schematic later if needs be.
Can anyone help?