Source for liquid sensor

allscott · Mar 17, 2008

I am looking for a sensor that activates when it gets wet. I need it to either switch a set of contacts or trigger a 24V sink PLC card. I know I've seen one of these before that looked like a hockey puck and seemed to work good but I can't remember who made it.

Does anyone know of a sensor like this that they could recommend? Google just can't seem to find what I am looking for.

rdrast · Mar 17, 2008

Something like http://www.ia.omron.com/product/family/568/index_fea.html ?

milldrone · Mar 17, 2008

Allscott,

This may not work for you. I have used a micro switch with a lever actuator and an asprin tablet to hold the lever up. when the tablet gets wet it softens and the lever moves down. It helps to bend the lever so only the very end is in contact with the tablet. The advantage of this setup is it can sense the very bottom of a cabinet or the floor. Thus the cabinet or room does not need to have a half an inch of water to trip the alarm.

TConnolly · Mar 17, 2008

Instead of looking next door look in the backyard.

http://www.plctalk.net/qanda/showthread.php?t=26970

Also, take a look at the Tracetek system.
http://www.tycothermal.com/assets/Americas/English/Document/Miscellaneous/1882/H55474_TTCommercialBrochure_0107.pdf

parky · Mar 17, 2008

The omron system consists of a controller (this can be used as a single probe system or two probe i.e. on/off on probe level or on when top level covered & off bottom level uncovered).

However these are no good on oil based liquids you would need a capacitive probe or a mowbrey type float switch.
the controller has a relay output with two inputs + ground it uses the resistance of the liquid to detect between the probe(s) & the ground connection.

allscott · Mar 17, 2008

Alaric said:
Instead of looking next door look in the backyard.

I tried the backyard, just never thought of searching for wet floor sensor.

Anyway thanks for the link, I think the waterbug will do exactly what I am looking for.

Milldrone I like your ingenuity. It might be interesting trying to write a SOP on what to do when the sensor "trips" though.

milldrone · Mar 17, 2008

Allscott,

How about the old saying "take two and call me in the morning"!

Maj. Toxido · Mar 20, 2008

allscott said:
I am looking for a sensor that activates when it gets wet. I need it to either switch a set of contacts or trigger a 24V sink PLC card. I know I've seen one of these before that looked like a hockey puck and seemed to work good but I can't remember who made it.

Does anyone know of a sensor like this that they could recommend? Google just can't seem to find what I am looking for.

I would recommend Endress and Hausser brand of sensor. I`m using it in all my level controll in all types of liquid application.

Regards:

Sherwin

Maj. Toxido · Mar 20, 2008

allscott said:
I am looking for a sensor that activates when it gets wet. I need it to either switch a set of contacts or trigger a 24V sink PLC card. I know I've seen one of these before that looked like a hockey puck and seemed to work good but I can't remember who made it.

Does anyone know of a sensor like this that they could recommend? Google just can't seem to find what I am looking for.

I will recommend Endress and Hausser sensor. I`ll been using it in all of my liquid type application.

Regards:

Sherwin

Sorry I`ll sent it twice

plcsoftvsd · Mar 20, 2008

I use Telemecanique liquid level relays for this purpose.

The two electrodes are kept on each side of a puck.

cheers.

Source for liquid sensor

allscott

Member

rdrast

Lifetime Supporting Member

milldrone

Member

TConnolly

Lifetime Supporting Member

parky

Member

allscott

Member

milldrone

Member

Maj. Toxido

Member

Maj. Toxido

Member

plcsoftvsd

Member

Similar Topics