Last weekend I decided that I would make my own:-

"Water top up resovoir system" for the cell set-up. which includes a small pump a resovoir (of course) two sensors (low and high water level) and the necessary circuit board to control all this. I have the design for a tried circuit.

So off I went to Maplins (the electronic kit supplier nearest to me) and duly purchased the suitable components, Resistors, capacitors, diodes etc, etc . and esconced myself in my office with the soldering iron and my elecrtonics tools. I sorted out the Resistors and found what I thought was the right ones for the right positions and off I went.

All went well until I tried to read the actual value codes on the resistors (which consist or coloured bands around something the size of a matchstick in diameter and about the size of a pea long. so I struggled. I sought younger assistance and they couldnt tell what was red and what was brown so I "soldered" (:o)) Tee Hee !) on, when we thought I had it as right as I was going to get it with the resistors that I had.

I attached the motor and relay and tube and, and ! and duly filled the resovoir ( a large plastic milk bottle) and plugged it in and the pump started, as it should, and the resovoir started to fill up ! and up ,over the top sensor and up until I grabbed the wire from the battery to jerk it free from the battery and stop the resovoir overflowing.Buuuuuuuut!!!!! I inadvertantly caught the filling pipe which was just laid into the resovoir from the pump knocking it out of the resovoir where it waved about spraying water everywhere, it was like a Circus clown show and the favorite water squiriting act. I grabbed the live end of the pipe to control it ( given that there is High power electronics around on the same bench) as if I was trying to choke a snake and within a second I was soaked I managed to remove the battery supply wire but it was too late (water and I seem to have this attraction) I was soaked

So yesterday I decided, with some help, that as the pump failed to stop when the water reached the top sensor, that I have a fault in my build and having more throughly checked the resistors found that I have several ( most) in the wrong positions Doh!

Now give me a hammer and I`m O.K! "Stick to what you know????? Difficult if you know "nothing?" like me :o((