22
HDK-MT350_EN_06
Installation
Only authorized and qualified specialist personnel may carry out work on
pipes and electrical systems.
As soon as the dryer has been set up at its installation location, you can install
the compressed air infeed and outlet lines make the electrical connections.
Recommended installation
We recommend the following installations to ensure reliable operation:
Bypass line
A bypass line can be provided for when the dryer is not in operation (e.g.
during maintenance) and the compressed air system still needs to continue
operation. The bypass line is a "detour line", which allows the compressed air
system to continue operating even whilst maintenance of the dryer is in
progress. However, during this time the air is not dried but flows through the
bypass line past the dryer and through to the actual loads. Filters in the
bypass line are meaningful so that the actual loads are largely protected
against dirt, water, and oil droplets even whilst maintenance is in progress.
Pressure retention valve
A pressure retention valve is essential if the dryer is frequently operated in
cut-out mode (discontinuous operation).
A pressure retention valve prevents excessively high flow occurring in the
dryer or in the desiccant bed when starting up in a depressurised line system.
A pressure retention valve allows the pressure in the dryer to build up slowly
as the valve only opens on reaching a defined minimum pressure. The
pressure retention valve is installed downstream of the dryer.
Compressed air tank
The dryer used compressed air during the regeneration process. When the
compressor is in no-load state, this regeneration process cannot be
completed without an external compressed air supply. The compressor stores
compressed air in a compressed air tank. When the compressor is switched
off, compressed air consumption is temporarily covered by this stored
volume.
Regeneration gas return
With the compressor in no-load state, the regeneration gas return is used to
continue regeneration when the pressure at the dryer inlet drops and the
regeneration started in a tower has not yet been completed. The
corresponding expansion valve only closes when regeneration is completed.
In standby mode, the control system remains on, and the dryer is ready for
the next switchover, which is made as soon as the compressor is switched
on.
Automatic condensate drain at prefilter
An automatic condensate drain should be used to ensure the condensate is
drained off from the prefilter at regular intervals.
