Pressure sensor membranes

[Ram80]

Does anybody have any experience using membrane pressure sensors. I want to build a device that measures water pressure, drops of rain, and want to use a membrane sensor to do this.

There are various different technologies such as FSR, Capacitive , Pressure Sensors, piezoelectric, Piezoresistive, optical, strain gauge, MEMS, Resonant, Inductive.

And there's the issue of making it waterproof.

Would something like this be able to do the job?

￡1.60 | Load Cell Resistive Membrane Pressure Sensor Module Flexible Force Sensitive Analog FSR402 4mm 5mm 7mm 110mm
https://a.aliexpress.com/_EHIBSc9

[Poroit]

Are you wanting to measure rainfall?

[Ram80]

Are you wanting to measure rainfall?

Well rainfall was just an example,  water pressure in general such as flowing water in a cavity. So I need the right sensor, for it to be waterproof or able to be covered by waterproof material and it took be sensitive and accurate enough for water pressure to activate the sensor.

[voltsandjolts]

I work with water pressures up to 15,000psi.
What pressure range do you wish to measure exactly?

[Ram80]

I work with water pressures up to 15,000psi.
What pressure range do you wish to measure exactly?

Very small compared to 15k psi probably up to 5psi.

[voltsandjolts]

OK, I assume that's 5 psig (gauge pressure, so 0-5 psi above local atmospheric pressure, which is roughly 14.7 psia at sea level).

What sort of device do you want to build?...

   Do you want a standalone unit with a display?

   Are you going to be programming a microcontroller, or should this be a 'hardware only' solution (e.g. op-amps only)?

[Ram80]

OK, I assume that's 5 psig (gauge pressure, so 0-5 psi above local atmospheric pressure, which is roughly 14.7 psia at sea level).

What sort of device do you want to build?...

   Do you want a standalone unit with a display?

   Are you going to be programming a microcontroller, or should this be a 'hardware only' solution (e.g. op-amps only)?

A device that will measure the pressure of a flow of water, probably into a cavity .

I don't really need a display, I thought a nand ram chip and USB so I can transfer data.

Yes it will have an MCU like the stm32,

I'm new to these sensor and don't know what their capabilities are, for example if you drip water onto these sensors would that register a reading or if your flowed water onto them would they be sensitive enough to measure a range of different water pressures.

[Poroit]

So 5psi gauge.

How are you planning to install the pressure transducer?

Do you want a threaded male process connection?

[BeBuLamar]

I am not sure if the OP wanted a pressure sensor. I think the OP wanted to measure the force of the water drop striking the sensor or a flow meter. To have 5PSI of pressure the water has to be collected in a vessel 138 inches deep.

[voltsandjolts]

The OP is very vague on what is actually required, so it's hard to help.

[BeBuLamar]

There is little pressure for what the op is trying to measure. I think it's best to use capacitive sensor.

[voltsandjolts]

OP wants to measure "pressure of flow"...so it's not clear to me if they actually need a pressure sensor or a flow sensor 

[BeBuLamar]

Yes and the sensor the OP wanted to buy is a load cell which measures force acting on it not a pressure sensor. 

[CatalinaWOW]

Those membrane force sensors probably have applications, but my experience trying to use them for calibrated responses leads me to recommend against it.  The are cheap, small and easy to interface but the good ends there. Drift or aging is huge and the response is very sensitive to the shape and location of the force application.

[Ram80]

Those membrane force sensors probably have applications, but my experience trying to use them for calibrated responses leads me to recommend against it.  The are cheap, small and easy to interface but the good ends there. Drift or aging is huge and the response is very sensitive to the shape and location of the force application.

This is what I was looking for, that they are not really suitable due to lack of accuracy. I've since discovered dedicated pressure sensor transducers. They will probably be the best bet. Such a learning curve.

[BeBuLamar]

Those membrane force sensors probably have applications, but my experience trying to use them for calibrated responses leads me to recommend against it.  The are cheap, small and easy to interface but the good ends there. Drift or aging is huge and the response is very sensitive to the shape and location of the force application.

This is what I was looking for, that they are not really suitable due to lack of accuracy. I've since discovered dedicated pressure sensor transducers. They will probably be the best bet. Such a learning curve.

I still don't know what you try to do. Can you explain further?