When I convert my ODV file to netCDF, I get error 42: Time-series with Depth parameter not constant

For a timeseries, Depth is not mandatory, but if it exists in the file it must be constant for all the duration of the time series.

If Depth varies in your measurements, you have to add another constant P01 parameter (depending of P02:AHGT)  like for example: MAXWDIST, Maximum depth below surface of the water body.