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Operation & maintenance manual, Drum filter HDF 12/16/20/24 -series
In certain configurations, an external emergency overflow is used in the event of electrical power
outages, for example, to avoid subjecting the filter fabric to excessively high pressure differences.
5.3 Electrical connection
Electrical connection must be done in accordance with local regulations. Check that the settings
on the motor protection device correspond with the motor data (see Appendices A and D).
5.4 Equipotential bonding
The Hydrotech Drum Filter and associated equipment should be protected with a sui-
table system for potential equalisation. This is very important to prevent galvanic cor-
rosion. Ideally use a cable with a cross section of 10-16 mm2. The cable should be con-
nected to the same electrical potential as the drive system.
Qualified and skilled electricians must perform all electrical work.
5.5 Checking drum rotation
Start drum rotation and check that the drum rotates in the same direction as the rotation arrow
on the drive unit cover.
5.6 Pipe connections
Nominal pipe dimensions are specified in the section
Technical specifications, Appendix A. The water’s inlet
speed should not exceed 1 m/s. Piping for discharge of
sludge water must have a minimum downward tilt of 1%.
5.7 Backwash system
Newly connected piping systems for wash water should
be flushed for at least 10 minutes before they are con-
nected to the filter. Carefully check that the nozzles are
not blocked. Any particles in the backwash water supply
must be removed. A standard wash water filter can nor-
mally be used to remove these particles (also see section
8.2).
5.8 Filter placement
When placing the filter it´s recommended to have typi-
cally 1000 mm of free space on surrounding the filter to
allow for easy access. In cases where it isn´t possible to
have a free space buffer of 1000 mm it´s advisable to
have not less than 600 mm of free space.
Figure 5.2 Filter seen from above
