Electrical Measurements | Describe different types of errors in analog measuring instruments.

Describe different types of errors in analog measuring instruments. 

Ans:

Types of Errors in Analog Measuring Instruments:

A) Gross error: These are due to mistakes on the part of person using the instrument.

B) Systematic Error: It has three sub types as: 

i) Instrumental Error: These errors are caused due to the mechanical structure of measuring instrument.  

    a) Inherent shortcomings of instruments: Instrument may read too low or too high. 

    b) Improper use of instruments: Improper handling e.g. overloading, overheating, failure to adjust zero, use of high resistance leads. 

    c) Loading effect: Cause distortion in original signal. 

ii) Environmental error: These are because of surrounding conditions such as temperature, pressure, humidity, dust, vibrations or external magnetic fields or electrostatic fields. 

iii) Observational Error: Parallax errors, incorrect multiplying factor.

C) Random error: These persist even after gross and systematic errors are removed.