Question

A (0−500) V range voltmeter has an inaccuracy of ±0.01% of its full scale. Calculate the % error in the instrument if the expected value is (i) 150 and (ii) 380.

Answer 1

To calculate the % error in the instrument, you need to know the full scale of the voltmeter and the inaccuracy. The % error depends on the expected value as well.

Step-by-step explanation:

To calculate the % error in the instrument, we need to know the full scale of the voltmeter and the inaccuracy.

For a (0-500) V range voltmeter, let's consider two scenarios:

(i) When the expected value is 150:

The full scale of the voltmeter is 500 V.

The inaccuracy is ±0.01% of the full scale, which is ±(0.01/100) * 500 = ±0.05 V.

The % error would be (±0.05 V / 150 V) * 100% = ±0.03333%.

(ii) When the expected value is 380:

The % error would be (±0.05 V / 380 V) * 100%

= ±0.01316%.