Sterling SDF 250 - Manual (Page 53)

SDF 250/400/500
Functional description 6-16
6.1. General Information
The dryers work according to the dehumidified air principle, i.e., the air is not only heated but also
dehumidified before it flows through the drying hopper.
In this manner, plastic granules can be dried down to a very small residual moisture content.
The drying takes place continuously, i.e., there are no rest periods due to regeneration of the
drying agent.
F
The dryer is rated for continuous operation.
All function sequences are fully automatic.
The dryer is equipped with two drying cells. One drying cell is part of the drying cycle; the other
drying cell is regenerated simultaneously.
If a malfunction occurs in the drying cycle during the program run, regeneration is not interrupted,
but continues until the program end has been reached. This guarantees that one regenerated
drying cell is always available.
The air inside the switch cabinet is cooled by a cooling appliance for the protection of
temperature-sensitive components (if present, optional).
With the digital timer (optional) the dryer can be switched on and off at set times.
Dew point dependent regeneration switch (optional)
The dew point temperature is monitored continuously. The valve system switches to the freshly
regenerated drying cells only after the selected dew point temperature has been reached. The
humid drying cells are then regenerated. After the cooling time the drying cells are ready for
operation again. The valve system switches to the freshly regenerated drying cells only after the
moisture content of the drying cells which are in the drying cycle have reached the setpoint value.