Accuracy of Adafruit MPRLS Ported Pressure Sensor Breakout

Breakout boards, sensors, other Adafruit kits, etc.

Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.
Locked
User avatar
Tim_BL
 
Posts: 2
Joined: Sun Sep 25, 2022 6:20 am

Accuracy of Adafruit MPRLS Ported Pressure Sensor Breakout

Post by Tim_BL »

I would like to understand the accuracy/resolution of the Adafruit MPRLS Ported Pressure Sensor Breakout - 0 to 25 PSI at very low pressures. I am trying to develop a pressure of 1 Pa very close to the zero advertise. Clearly the vacuum developed is dependent on the vacuum pump but according to the reading from the sensor I am some 260 Pa away from that objective. This is my second Adafruit MPRLS, as I somehow burn out the first one, but that first sensor gave a repeated reading of approximately 180 Pa less than the current one. So which is correct? or closest to correct! To add to my confusion on the product link to the Honeywell page it states the range being 60 mbar to 2 bar. Clearly, I am getting a lower reading than this but whose claim to the low pressure should I rely on. As I am unable to calibrate these sensors I can't work out if the high reading is due to the pump, vacuum chamber or the sensor. Your thoughts please. The sensor is connected to Arduino board with built-in Wi-Fi

User avatar
adafruit_support_bill
 
Posts: 88037
Joined: Sat Feb 07, 2009 10:11 am

Re: Accuracy of Adafruit MPRLS Ported Pressure Sensor Breakout

Post by adafruit_support_bill »

To add to my confusion on the product link to the Honeywell page it states the range being 60 mbar to 2 bar. Clearly, I am getting a lower reading than this
Many types of sensors produce non-linear output as they approach the physical limits of their response. For MEMs type sensors in particular, this is where minor manufacturing variations start to become apparent. In this case, Honeywell has determined that 60mbar is the minimum level at which they can guarantee reliable measurement with this device. It is not unusual for a sensor to produce readings above or below the manufacturer's rated range. But the accuracy of such readings is not guaranteed.

User avatar
Tim_BL
 
Posts: 2
Joined: Sun Sep 25, 2022 6:20 am

Re: Accuracy of Adafruit MPRLS Ported Pressure Sensor Breakout

Post by Tim_BL »

Thank support_bill, that makes sense. Just one additional question, the reading jumps around a little at the bottom end by +/- 5 Pa and occasionally +/- 10 Pa could this be a result of the sensor rather than the atmosphere it is in.

User avatar
adafruit_support_bill
 
Posts: 88037
Joined: Sat Feb 07, 2009 10:11 am

Re: Accuracy of Adafruit MPRLS Ported Pressure Sensor Breakout

Post by adafruit_support_bill »

If it is jumping around randomly, I'd suspect that it is sensor noise. If it is drifting slowly, it could also be a leak in the system.

Locked
Please be positive and constructive with your questions and comments.

Return to “Other Products from Adafruit”