Supply voltage.
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The op amp you have chosen requires a negative supply voltage which you haven’t indicated that you have. The data sheet indicates it needs +-5V to +-15V to operate correctly.
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Waste of time.
I am sorry if it appears as if I am adamant to correction. The problem I am facing is that most of the components you are mentioning aren't readily available in my country.
I couldn't get mcp6002 from any store in Nigeria.
I don't have the +/- power supply but I could build one as the components required are available at stores close by.
What else do I need to prepare or setup for it to work properly?
You don't have to use a bipolar supply, because an Arduino can't read negative voltages either.
Google something like "single supply instrumentation amplifier schematics" (images).
There are also two-opamp versions.
Leo..
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Hi Leo, I suggest that the real answer is you need to use a supply with the positive a bit more than the highest voltage you want to amplify and the negative a bit less than the lowest voltage you need to amplify, with a reference of some kind in between the 2. In practice that means either a split supply with 0V as the reference or a 0V and +ve supply with some kind of mid point between the 2, probably created by a resistive divider. Exactly what is best depends on the application.
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I seacrhed in vain for a datasheet, all I could find was this:
Measure the branch resistances R1, R2, R3, R4 and post values.
Then if you join 1 - 6 you have a wheatstone bridge circuit.
Your LM358 will run nicely from 5V. You can use this circuit
but you may need to reduce the resistor values eg R2 = 1M, R1 = 33k.
You will not get 0-5V output because its not a rail-rail op amp; you would need to use split supplies of at least +8V, -3V.
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I'm pretty sure the device is a "Pressure Sensor MPS20N0040D-S."
The relevant part of the data sheet is :
See post #90.
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Can you use this supplier?
https://www.jumia.com.ng/generic-cjmcu-333-ina333-human-micro-signal-multifunctional-three-op-amp-precision-instrumentation-amplifier-138884035.html
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That would be a great choice!
What I have been trying to hint several times is that the output of an LM358 can go to the negative rail, but not fully to the positive rail. So you don't need a negative supply, but you do need a positive supply that is at least 1.5volt higher than the output voltage you want to reach. Same for the inputs of this opamp. Keep it between 0volt and "VCC - 1.5volt".
Leo..
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I really appreciate your help. Thank you very much. The problem with the store is that they will be shipping from abroad:
I need to be done with this before 21st of this month.
Thanks for your help from the start.
Thank you. This worked.
The info you requested for: R1= 4.82k R2= 4.85k R3= 4.83k R4=4.85
My sensor is a lot like the "MPS20N0040D-S" mentioned by EmilyJane which is quite like the one you posted. The only differnce being the pin configuration. In comparison, the +output is taken from pin 4.
I have two types of LM358p. The two behave somewhat differently (Especially when the resistor values are small).
I observed that the higher the resistor values, the more accurate the output of the LM358 op-amps.
Thanks again everyone.
Then make a two-opamp instrumentation amp.
Note that an instrumentation amp has no resistors (loading the sensor) on the two inputs.
Leo..
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Oh, sorry, I thought it was a Nigerian store. Oh, well. 
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