Advantages of Digital Voltmeter:
1. Greater speed
2. Higher accuracy and resolution
3. No parallax error
4. Reduced human error
5. Compatibility with other digital equipment for further processing and recording.
Disadvantages of Digital Voltmeter:
1. While measuring under 1mV for AC and under 100μV for DC, the noise and drift will cause the last digit or last but one digit to fluctuate a lot. Hence it is more difficult to estimate average reading under these conditions.
2. Adjustment of the reading to a certain value, even to a minimum or maximum, isn’t convenient with a digital instrument.