Water Pressure Sensor needed !

Hello,

I am searching for a water pressure sensor, with a 0~15 bar rating. easy to interface with arduino.. any ideas ?

Thanks all

Which sensors have you checked already?

15bar is quite a lot or?

Can you tell more about the project, there may be indirect ways to measure the pressure?

Ok, I need to build a water pressure regulator.. I'll attach a pressure sensor & a solenoid valve to a medium pressure tank.. and regulate the pressure to be fixed from 2 to 6 bars..

this is the basic idea.. do you have better one ? I found this sensor http://www.digikey.com/scripts/DKSearch/dksus.dll?vendor=0&keywords=NSCDANN150PGUNV And i think it can do the job..

This tank will supply water to other solenoids.. the reason for this regulator that I need to deliver the same water pressure on each valve in the allowed range for them..

Got me ?

the sensors your link points to go to 10 bar. in your first post you mention 15 bar. that's quite a difference.

For the rest it sounds like a decent sensor. What is the accuracy you need? steps of 0.1 bar sufficient?

0.1 bar steps is great.. and I said 15 bars for more choices .. but 10 bars will be good

you still have to amplify the signal [linear] about x150 .. x200 as its output range is between 0 and 20 mV .

you must be able to handle 10bar == 5V 0 bar = 0V so your working range between 1 and 6 bar is approx 0.5 .. 3Volt.

You get 500 steps in this range giving you a resolution of max 0.01bar but due to noise it will probably 0.1 bar at best.

So it might make sense to use an external reference for your analog read. Set it to 3.5Volt and you get 1023 steps between 0 and 6.5 bar (approx) which gives you control twice the resolution in the order of 0.05 bar.

Hope this helpes

First, Where I can find this sensor ? Where I can get one ?

The output is differential, so I suggest you use an instrumentation amplifier to amplify it, for example http://uk.farnell.com/analog-devices/ad623anz/ic-instr-amp-800khz-110db-8dip/dp/9603700. It's a ratiometric device, so for best accuracy, Vref for the Arduino ADC should be the same supply that is powering the transducer (e.g. +5V).

Thank all for helping.. But I still don't know what is this decent sensor.. and where i can get one !? And about this one http://www.digikey.com/scripts/DKSearch/dksus.dll?vendor=0&keywords=NSCDANN150PGUNV , i think this one easier in using.. I can connect in directly to analog pin.. Right ?

Albatroon: Thank all for helping.. But I still don't know what is this decent sensor.. and where i can get one !? And about this one http://www.digikey.com/scripts/DKSearch/dksus.dll?vendor=0&keywords=NSCDANN150PGUNV , i think this one easier in using.. I can connect in directly to analog pin.. Right ?

No, the output from that sensor is only 25mV at full pressure. That's why I suggested you use an instrumentation amplifier with it.

Albatroon: Hello,

I am searching for a water pressure sensor, with a 0~15 bar rating. easy to interface with arduino.. any ideas ?

Thanks all

I use Grainger.com p/n 5LRX0 for my pool This only goes to 30 psi but they have similar models that go higher. It has 1-5 volt output that's easy to use with arduino.

dc42:

Albatroon:
Thank all for helping… But I still don’t know what is this decent sensor… and where i can get one !?
And about this one http://www.digikey.com/scripts/DKSearch/dksus.dll?vendor=0&keywords=NSCDANN150PGUNV , i think this one easier in using… I can connect in directly to analog pin… Right ?

No, the output from that sensor is only 25mV at full pressure. That’s why I suggested you use an instrumentation amplifier with it.

Thanks… I’ll try it…

ScottG:
I use Grainger.com p/n 5LRX0 for my pool This only goes to 30 psi but they have similar models that go higher. It has 1-5 volt output that’s easy to use with arduino.

little high price… but i’ll give it ashot… thanks

Here's one with a built-in amplifier: http://www.digikey.com/product-detail/en/P51-200-G-B-I36-4.5V-000-000/734-1008-ND/1665769.

dc42: Here's one with a built-in amplifier: http://www.digikey.com/product-detail/en/P51-200-G-B-I36-4.5V-000-000/734-1008-ND/1665769.

Before I order this one.. just for Confirmation.. This sensor will work with water & I can connect directly to Arduino? Right ?

I've only skimmed through the datasheet, so I suggest you read it more thoroughly to determine whether it meets your requirements. You might also like to look at the Product Training Modules that are linked to on that page. I picked the 200psi version because it's closest to your original requirement of ~15 bar range. There are other sensors in the same range that might meet your requirements better, see http://www.digikey.com/product-search/en?FV=ffec5663.

The one you linked to meets my requirements.. I'll order them.. Thanks

I think I'm a little bit late. I like these water pressure sensors: http://www.amsys.de/products/ms5803.htm

This sensor will work with water & I can connect directly to Arduino?

I have used several of these SSI units for water pressure regulation. 50 PSI and 100 PSI units with either .5-4.5v or 4-20ma outputs. They are a good but economical units. Just be careful when you mount them (as with other makes) that the orifice is pointing downwards as bits of sediment, grit, etc tend to settle inside and build up on the diaphram ruining the accuracy of the sensor.

One last question.. What is the difference between the Absolute sensors and the Gauge sensors.. what I found that the Gauge sensors can't read pressure at 0 PSI, only Absolute can do this.. I found this :

Found Here : http://dkc1.digikey.com/us/en/tod/SSI/P51-Pressure-Measurement_NoAudio/P51-Pressure-Measurement_NoAudio.html page 5

Will I use Absolute sensors ? will do the job ? Will give a accurate measurement from 0 pressure to maximum sensor rate ? Or just use Gauges ?

Thank all

For most applications it is the pressure above atmospheric that counts (e.g. in determining flow rate, if the water flows to a tank that is not sealed); so the vented gauge sensor is usually most appropriate.