Hi

Anyone know where I can get formulae to convert voltage to pascal

Thanks

Please clarify, I have no idea what you are asking. Voltage and Pressure are completely different phenomena.

Have an experiment where a syringe is used to compress air. The compressed air is converted to a voltage on a multimeter. Have the amptitute gain and the sensor sensitivity.Am looking for a formula to convert the voltage to pressure i.e.. Pascals

Anyone have the formula or know where to get it.

Many thanks

Quote:

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Originally Posted by im-fran

Have an experiment where a syringe is used to compress air. The compressed air is converted to a voltage on a multimeter. Have the amptitute gain and the sensor sensitivity.Am looking for a formula to convert the voltage to pressure ie. pascals

Anyone have the formula or know where to get it.

Many thanks

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This is one for the homework board.
It all depends on HOW you convert (air) pressure into voltage. You can do that in a linear and/or a non-linear way. It all depends on HOW !

You need to know how the sensor is calibrated, and how it works!

I have an experiment where a syringe is used to compress air. The compressed air is measured using a pressure sensor which converts to voltage on a multimeter. I need to transfer the volts to pascals. I know that the sensor voltage output is directly proportional to the pressure exerted on the sensor. We know the sensor sensitivity, the dc supply voltage, and the amplifier gain. Have been trying to figure it out for days! Any ideas?

You need to calibrate your device. I suggest starting with the plunger removed so that you have 1 atmosphere pressure in the syringe, and measure the voltage. Then insert the plunger and compress the air to half the syringe's volume, and wait a bit so that the air inside the syringe gets back to room temperature (it may heat up a bit when you first compress it). The pressure inside should now be 2 atmospheres - take another voltage reading, and the difference in the two voltage readings is due to 1 atmosphere pressure. Now you know how many volts = 1 atmosphere.

I am having a simlar problem with a permeability rig. I am using a syringe pump to pressurise a cylinder which has a pressure transducer attached. This is connected to a voltmeter but I need the pressure in Pascals?

From what I gather, these units are used in microphone sensitivity.

A typical "open-circuit sensitivity" spec is 5.5 mV/Pa for a condenser microphone and 1.8 mV/Pa for a dynamic microphone.

For what it's worth. I don't know if that'll help or not.

G'day the ratio is 1:5
1 2 3 4 5 Volts
4 8 12 16 20 mA
3 6 9 12 15 psi
20 40 60 80 100 kpa