Hi David,
Freescale pressure sensors are not manufactured to be submerged in water. However, the MPXM2010GS can be used to measure tank levels by using the column of air method. The sensor will read the change in pressure in the column of air as the tank fills or empties.
AN1950 - Water Level Monitoring:
http://www.freescale.com/files/sensors/doc/app_note/AN1950.pdf
AN1516 - Liquid Level Control Using a Pressure Sensor:
http://www.freescale.com/files/sensors/doc/app_note/AN1516.pdf
AN3728 - Media Compatibility for IPS PRT Pressure Sensors:
http://www.freescale.com/files/sensors/doc/app_note/AN3728.pdf
Regards,
Tomas
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