Author Topic: MD-PS002 pressure sensor from Aliexpress - pressure range  (Read 2031 times)

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Offline matkarTopic starter

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MD-PS002 pressure sensor from Aliexpress - pressure range
« on: March 27, 2017, 10:31:39 pm »
I bought two pieces of pressure sensor here:
https://www.aliexpress.com/item/2pcs-lot-pressure-sensor-air-pressure-Tire-pressure-sensor-700kpa-diffusion-silicon-A1G1/32502253913.html?spm=2114.13010608.0.0.5GoaWW
In the title it says they are 700kPa sensors but down in description it says their range is 150kPa from absolute zero. I've asked the seller but doesn't seem to know which data is correct.
I have found these datasheets: http://www.datasheetspdf.com/datasheet/MD-PS002.html
The second datasheet in chinese has a table with multiple sensor options. There don't seem to be any markings on the sensor body...

How can I tell which model do I have without risking destroying the sensor?
According to the table on the first page the 700kPa sensor has a full scale range of 100mV. Does this mean by applying 5V between IN+ and IN-, I should be reading 100mV differential between +OUT and -OUT at 7 bar (and proportionaly less with lower pressure)?
 

Offline danadak

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Re: MD-PS002 pressure sensor from Aliexpress - pressure range
« Reply #1 on: March 27, 2017, 10:46:56 pm »
Assume you have the lower pressure sensor, and place that DUT under max
pressure and measure output. That full scale V should indicate which part it
is.

This whole thing is risky if you are doing any life support work, definitely get
marked parts.

Chinese knock off parts always tempting, but have a "real" price that may be
unacceptable, like not telling you which part you have. Some parts are the
correct part, but do not meet advertised specs.


Regards, Dana.

Love Cypress PSOC, ATTiny, Bit Slice, OpAmps, Oscilloscopes, and Analog Gurus like Pease, Miller, Widlar, Dobkin, obsessed with being an engineer
 
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Offline matkarTopic starter

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Re: MD-PS002 pressure sensor from Aliexpress - pressure range
« Reply #2 on: March 28, 2017, 07:53:29 am »
I did a very crude measurement.
I've attached a hose filled with water to the sensor and measured the response by lifting the hose to a known level. With 5V applied at zero level the reading was 8,68mV. When the water level was elevated to 216cm (21,19kPa) the reading increased to 11,63mV.
21,19kPa/2,95mV = 7,18kPa/mV -> 718kPa/100mV. This is close enough to 700kPa/100mV from datasheet so I guess it's save to say it's a 700kPa sensor.
 


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