Nadivalaya has two plates, facing North and South, which are the dials. The walls containing these plates are inclined towards the South at such an angle, that they are parallel to the plane of the equator of the Earth. The rods emerging perpendicular from the plates, are parallel to the axis of rotation of the Earth. The shadows of these rods, move along the scales on the dial plate, indicating the time. The entire dial plate, can be divided into 24 equal hours and further subdivisions. The zero of the scale is marked at the top and the bottom end of the dial plates so that one could read the time starting either from the solar noon or the solar midnight. To the time indicated by the circular scale, a correction factor as displayed at the observatory, for the day, needs to be added, to obtain the clock time.
From the Autumn Equinox to the Spring Equinox, the dial plate facing south will be sunlit and is to be used for telling the time. From the Spring Equinox to the Autumn Equinox, the dial plate facing north is sunlit and is to be used for this purpose.