What are the main differences / advantages of ADC compared to a mechanical current meter?

FAQ - ADC - Acoustic Digital Current Meter

1. What is the minimum water depth for field deployment?
2. Is it possible to delete data on the handheld using the QReview software?
3. How often does the OTT ADC have to be recalibrated?
4. Is it possible to pre-configure measuring points/sites in the office?
5. Q: What are the main differences / advantages of ADC compared to a mechanical current meter? A: • No calibration needed. • No mechanical moving parts. • Integrated depth measurement. • Calculation of discharge. • Storage of all measurement values.  
   
   
6. What maintenance is necessary?