Operation Manual
RENNER Compressors
2 Machine Description
2-6
2.3 Compressor unit (contd.)
Compressor unit
Looking at the shaft from the front (see diagram), the screw-
type compressor rotates anticlockwise (see arrow on V-belt
pulley).
Intake air filter
The intake air filter, integrated in the housing, is mounted
directly on the intake flange of the intake regulator. The intake
air is filtered by means of a dry micro-filter with a rating of 10
µm. The filter can be cleaned several times before it needs
replacing. Use only original replacement filters!
Discharge pressure switch (electric)
The discharge pressure switch is connected to the machine
outlet by a pipeline. It controls the intake regulator. The values
for p
max
and p
min
are set at the discharge pressure switch:
p
max
: upper limit of operating pressure at which the unit cuts out
in normal mode
P
min
: lower limit of operating pressure at which the unit cuts in
again in normal mode
The discharge pressure switch is adjusted to the correct setting
at the factory. The discharge pressure switch may only be
adjusted by personnel authorised by the manufacturer!
Intake regulator
The intake regulator is mounted directly on the screw-type
compressor. It controls the air volume sucked in by the screw-
type compressor via the intake filter.
Functional principle of the intake regulator:
The intake regulator has only one master valve. This doubles
up as an infinitely variable control valve and a hermetically
sealed isolating valve. At full load operation the intake cross-
section is fully opened at minimal drop in pressure. At part load
operation the intake cross-section is automatically regulated by
the lift stop and adjusted to the actual air requirement.
When the machine stops this valve quickly and automatically
closes the entire intake cross-section. The multiple functions of
the regulator are discharged by just one flange-mounted control
unit.
Minimum pressure valve
The minimum pressure valve is located on the outlet of the
compressor unit upstream of the air aftercooler.
It performs two tasks:
1) As a pressure maintaining valve it prevents the drop in
pressure in the absence of counterpressure below a minimum
pressure of 4.5 bar.
Description
Compressor unit
components
