Pressure transducer


We are working on a project which includes a pressure transducer (Datasheet).

We tried connecting it to an Arduino uno with pin 1 in supply voltage 5V, pin 2 in a0 and pin 3 in gnd. We connected a capacitor(224nF) between pin 1 and 3 as listed in the datasheet. We measured voltage with a multimeter between pin 1 and pin 2. When pressure is aplied the voltage drops but the voltage should rise when pressure is applied.

Do you have any solutions or suggestions to this problem.

You would expect the voltage between pins 1 and 2 to drop as pressure increases. The voltage between pins 2 and 3 would rise. This is not a problem. Why are you concerned?

Measure the voltage between pin 3 and pin 2 and it will go the right way.

It is convention to always measure violates with respect to ground not the supply.

We measured correctly now (thanks btw), but the voltage still only raises slightly. At atmospheric pressure the output is 4.4V, and when pressure is applied it only goes up to 4.8V and peaks there even if more pressure is applied. Any solutions or suggestions? (The transducer is a 15 psi absolute pressure sensor)

What is the exact model number of the sensor? If it is an "absolute" type, then zero volts output corresponds to a vacuum and 15psi is approx 1 atmosphere. 4.8V is as high as it will go. Maybe you purchased the wrong type of sensor?

It is an absolute pressure sensor. The link for the model is here

I updated my post above (sorry). Please re-read.

Okay, so a gauge sensor would en better? I Think about a 15psi gauge sensor instead?

Yes, I suspect so, but of course I don't know exactly what you are measuring the pressure of.

I am measuring the pressure in a pressure tank. The maximum pressure in the pressure tank is 6psi.

So that's 6 psi above atmospheric pressure? And you want to measure the pressure over and above atmospheric? In that case the 15psi gauge sounds ok. But something with a slightly lower maximum would give you more precision.

Yes I want to measure Above the atm. So thanks for your help!