MPX5700AP

Other Hardware Sensors
1

Hi ,

I am new in ardunio forum.. thanks for everything..

I have a mpx5700ap sensor. ı want to mesaure system pressure by using mpx5700ap.

in device datasheet , transfer function is

Vout = VS*(0.0012858*P+0.04) ± Error
VS = 5.0 Vdc

my code is ;

int raw = analogRead(A0);
float voltage= raw0.0048828125; // 5/2^10 adc
float pressure= (((float)((float)voltage-50.04)/(5*0.0012858))); // kpa

and data sheet ;

http://www.nxp.com/assets/documents/data/en/data-sheets/MPX5700.pdf

now, mpx5700ap sensor's port is free but output kpa is 95 according to my code and output voltage 0.8 , why ?

1 atm to kpa ; 101 , but i am reading 95... where is 6 kpa ? :frowning:

thanks everyone..

2

Is the 5v supply exactly 5v?

3

yes 5v sir

4

Figure 2. Output vs. Pressure Differential - from data sheet shows that sensor may outputs anything in between 0.7 - 1.0 V for 100kPa pressure. So its not very accurate.

5

15..700 kPa
Where do you measure the pressure?
+/- 2.5% => +/- 17kPa