Electronic Alarms and Home Security Devices - Low Tech Water Sensor

I'm trying to find a device that will sense if water is present and if so switch on a lamp. I'm trying to prevent water damage if my sump pump fails and water overfills the sump.

This will be used in a vacant house where the lamp will be in a window for neighbors to see if a problem.

I've seen a lot of devices that sound an alarm, dial a phone number, or send an e-mail but these will not work since no one is in the house and no phone/internet service.

I've also seen sophisticated X10 type devices but these seem to be over kill and overly expensive.

Any ideas?

You could use one of the basic electromechanical sensors like this one:

http://www.grisk.com/specialty/2600water_sensor.htm

You use this device to trip a relay to turn on your lamp. How easy this is for you depends on your degree of electrical/electronic knowlege.

Thanks. I saw these type of sensors but unfortunately I don't have any experience putting together the components required. I'm more of a software/hardware type than electrical but am very interested in picking up this knowledge. Any pointers that you know of?

Ok why not a device that makes noise...

Even if its a cheap noise alarm mounted just outside a window even if you have to place it in a Ziploc bag or a vacuum packed bag.

I have a couple of links for items under $20 bucks that would work.

http://testproducts.com/safecart/default.php/cPath/36/?source=Google&gclid=CJSokdHihYgCFRGXFQodm0nm9A

http://www.amazon.com/American-Science-Surplus-FLOOD-ALARM/dp/B00068866G
$6.95

This place has a bunch of stuff
http://www.cuttingedgeproducts.net/products.asp?categoryid=53

http://www.amazon.com/Sonin-03300-Wireless-Water-Alarm/dp/B00004W4B5/sr=8-2/qid=1161284015/ref=pd_bbs_2/102-6819494-3256930?ie=UTF8&s=hi

Also no reason you could not replace the buzzer with a relay and power a lamp or strobe.

Thanks as well. A lamp is best for this application due to the distance to neighbors. Also my son will be driving by on a daily basis and will look for the light.

I'd need a lot of help replacing an alarm with a relay to power a lamp.

Can you use a soldering Iron?

How about this... Its very LOW tech...

Get a bike reflector the type that FLASH.
http://brandscycle.com/itemlist.cfm?Category=88&searchtype=Category&catalogId=39



You can use the batteries to run it or buy a small plug in transformer to power it form a wall outlet.

Unsolder if you want to the switch that us used to turn it on but all you need to do is solder 2 wires from any cheap wire to where the switch is on the circuit board. Run the wire down to the sump pump area. Simply place the wires separated on top of a thin plastic (or any non absorbent surface) at the top of the pump area where it will get went when flooding happens. It should turn on the flasher when it floods.

Interesting. Thanks.

Based on some of the poor reviews I've read on water sensors this may even be more reliable. I may just try a variation of this suggestion. I did read somewhere that water is a poor conductor so it will be interesting to see how this all works out.

I'll post my final solution once I get one that works. I've got about ten days before heading south for the winter.

Water is, its the minerals in the water that allow it to conduct.
But all the switch likely does is is provide a logic high or low to the circuit and not a direct battery flow.

Hyper soak something like a paper towel ( or maybe a dense rag) in a salt / brine solution and let dry out. Then place it between 2 pieces of metallic screen ( the 2 poles, so be sure they don't touch. ) Hmm, the screen is propbably overkill, just the 2 wires, one on each side of the conductive paper. When the paper gets wet, it should conduct.

After giving this more thought, rather than going with the science project approach for a warning light I'm going for a full solution - an extra battery driven pump. For under $200 I can get the full setup including battery from Home Depot.

I'm thinking the reason I could only find an audible alarm device is that it only makes sense to warn you if you can take immediate action. A light in the window for a neighbor to see may not get noticed for a day or so in which case the damage has already started.

I may still put together something with a light to show that the backup system has kicked in (main pump failure) but I'd have several days for someone to investigate the problem.

Understandable. Since you admit to limited electrical assembly skills, this is probably your best and most reliable course. The wiring to do the light is actually pretty simple, but you have to have the basic understanding to follow the wiring diagram to pull it off.