Water presence detector

I made a water detector for my basement floor from a battery-operated smoke detector. I just replaced the smoke sensing element with two contacts that I melted into a piece of plastic located at the end of a bit of coax about 4 ft. long. It has worked for years. The advantages are that it's inexpensive (at the time, it was about $10 for a smoke detector), it operates on an ordinary 9 V battery, so it works even if there's a power failure, and it gives warning beeps when the battery starts to get weak. The disadvantages are that after the sensor gets wet, it has to thoroughly dry out before it'll stop beeping, so you have to remove the battery, or put an on-off switch on it as I did.

-- john

Here is a commonly used device:

I went to West Marine and got an inexpensive Bilge Pump float switch. I am a boater so that seemed like the logical way to go. Wire it with a 12V wall wart to power a buzzer / siren and you are ready to go. I eventually got the switches (I have 3 sumps) wired into the house security alarm system.

try those,

These might work . . .but no fancy controls.

Pubudu

Sounds good, I am a boater also and I will look for a float switch.

The old toilet bowl float on the end of an arm that closes a microswitch. Build a moat around your sump hole. Place the float gadget in the moat. When the moat has water in it, the sump hole is overflowing and the pump is not running.

Al