My sensor don't show zero en x-axis

Hi,
thanks very much, your response we clarified many things...
but we have a complication ...
We tested the sensor but it always shows a value on the x axis
suppose that because the sensor is not exactly parallel to the ground
there is a solution for this that does not involve using a stabilized platform
we are developing an inertial navigation system for a robot ....

thank you very much for the help

The accelerator sensor is not a precision instrument.

Just subtract the not-0 value from the x-readings.