Anyone know about level switches?

My pumped bath supply can overwhelm the overflow.
I want to fix something under the bath to turn the pump off at a certain level.
It's a jacuzzi bath so I do have access to hoses on the underside which I could use (I think) in the same manner as a washing machine level switch.


I'm not sure how they work - is it a pressure in a closed piece of pipe?
Can anyone suggest a suitable (common/generic) switch which might be suitable?

I can add a relay to use it with low voltage.

Hi Chris, almost right. have a look at the pressure chamber picture here

basicaly there is a "bottle" connected to the outer drum, as water fills it also fills the p.c. this in turn compresses the air in the p.c. this is detected by the pressure switch which is connected via a small pipe to the p.c.

you can adjust the pressure switch to your requirements (trial and error) but never do this with a washing m/c

also some pressure switches do have levels, so one of these may work for you.

The problem i can see for you is making a bottle to go on a pipe.

good luck

Hmmm, might be easier to stick (literally) a capacitive level detector on the outside of the bath. ABout £30 in RS. Got me thinking, have two - one for normal bath level - then I'd need a selector switch...