Question

A 0-150 V voltmeter has a guaranteed accuracy of 1% full-scale reading. The voltage measured by this instrument is 83 V. The limiting error will be nearly
1. 1.2%
2. 1.8%
3. 2.4%
4. 3.2%

Answer 1

Correct Answer - Option 2 : 1.8%

Guaranteed accuracy in percentage = 1 % of full-scale reading

Full scale reading = 150 V

Guaranteed accuracy error in volts \(= 150 \times \frac{1}{{100}} = 1.5\;V\)

So, while measuring 83 V on (0-150) V voltmeter, it may read (83 ± 1.5) V.

Limiting error \(= \frac{{1.5}}{{83}} \times 100 = 1.8\;\% \)