15
Operation and maintenance manual for
Hydrotech Discfilter HSF31-series
5.2.1.HANd.mode.–.continuous.rotation
During continuous drum rotation and backwash, the water level inside the
discs is kept nearly constant.
The maximum allowed difference
of the water level inside and outside
the discs is 250 mm during con-
tinuous operation (see
Figure 5.2.1
).
The recommended operational
difference is 100-200 mm. Long-
term operations with a pressure
differential exceeding the indicated
maximum will reduce life span for
and bearings and filtration media.
WARNING!
The filter should be installed so
that the differential pressure will
under no circumstances exceed
a maximum of 380 mm. The filter can withstand maximum pressure for a
limited period of time and only if the filter is stationary.
The level sensor and the automatic control system are disabled when HAND
mode is selected.
5.2.2.AUTO.mode.–.automatic.level.control
With level control, the disc rotation and the backwash pump is activated when
the water level inside the discs reaches the level sensor. If an independent
rinse water supply is used, the level sensor controls a solenoid valve instead
of the pump.
The water level inside the centre discs will vary when AUTO mode is selected.
The lowest level is just after a backwash cycle, and rises until the level sensor
is reached.
The maximum allowed difference
of the water level inside and outside
the discs is 300 mm during continu-
ous operation (see
Figure 5.2.1
).
The recommended operational
difference is 100-200 mm. Long
term operations with a pressure
differential exceeding the indicated
maximum will reduce life span for
and bearings and filtration media.
WARNING!
The filter should be installed so
that the differential pressure will
under no circumstances exceed
a maximum of 380 mm. The filter can withstand maximum pressure for a
limited period of time and only if the filter is stationary.
If a constant water level inside the drum is required, the filter should run
continuously (HAND mode).
Figure 5.2.1 Maximum allowed differential
pressure at continuous operation
Max. 250 mm
!
Figure 5.2.2 Maximum allowed differential
pressure in AUTO mode
Max. 300 mm
!
