A 0 - 25 Amp ammeter has guaranteed accuracy of 1% of full scale reading, the current measured by this ammeter is 10 Amp. The limiting error in percentage for this instrument is

Concept:

Limiting error: The maximum allowable error in the measurement is specified in terms of true value, is known as limiting error. It will give a range of errors. It is always with respect to the true value, so it is a variable error.

Guaranteed accuracy error: The allowable error in measurement is specified in terms of full-scale value is known as guaranteed accuracy error. It is a variable error seen by the instrument since it is with respect to full-scale value.

Calculation:

Given that, full-scale reading = 25 A

Guaranteed accuracy error = 1% of full-scale reading = 1% of 25 = 0.25 A

True value = 10 A

Limiting error \(= \frac{{0.25}}{10} = 0.025\)

Limitting error = 2.5%