Electronic instrumentation

Error

The error algebraic difference between the value read or transmitted by the instrument and the real value of the output variable.

Types of error.

Serious errors

Systematic errors

Environmental errors

Random errors

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Precision and Accuracy

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Precision

It is the reproducibility with which successive measurements of the same variable can be carried out under identical conditions.

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Accuracy

Accuracy is the ability of an instrument to give readings close to the true value of the measured quantity. It is a function of the repeatability, resolution and calibration of the instrument.

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Physical quantities in the electronic field.

Current (A)

Voltage (V)

Resistance (Ω)

Power (W)

Voltage (V)
V=W/A,
V=J(Joule)/Q(Coulomb),
V=eV(electrovolts)/e(electron-charge)

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Current (A)
A=Q(coulomb)/t(segundos)

Resistance (Ω)
Ω=[J(joule)*t(segundos)]/C^2(coulomb)

Power(W)
W=VA
W=(A^2)(Ω)
W=V^2/Ω