Hi,
Doing a search on quantity in stock here are some interesting sensors, that are available in quantity at reasonable price points.
One has an exposed back, the others are gauge type. It the body of the sensor was placed on one side of the flow meter constriction and the port ported to the other side, possibility that could suffice as the differential sensor.
The gauge type would be better for the pressure safety sensor.?
The down side of these sensors is they are analog. The?MP3V5004GP (0.57 PSI) sensor looks like it can supply an analog voltage direct to the microprocessor A/D convertor. The rest will need an op-amp amplifier to bring the signal to a level that can be converted by the microprocessor A/D. Don't know if we want to go there in a crunch project.?
The whetstone bridge type sensors should be able to handle positive and negative pressures, but will need to read the data sheets in more detail to see if that is a limitation.
These sensors are stocked in large quantities so manufactures must like these for some reason, so hopefully that means will continue to be easy to obtain over time.?
There are likely more sensors if we keep looking.?
1000 pcs prices:
MP3V5004GP - $7.58
MPXM2053GS - $5.019
MPX2300DT1 - $4.26
NPC-100T - $5.29 (there is also a NPC-120)
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