30
Temperature start-up protection
The screw compressor unit does not start up, if the
ambient temperature is lower than +1 °C.
Start-up protection of the electric motor
The screw compressor unit does not start up, if the sy-
stem pressure is higher than 0.8 bar.
7.3
Commissioning after malfunction
7.4
Operating modes
Automatic operation
The generation of compressed air is stopped when
the set maximum operating pressure has been achie-
ved, and the electric motor stops after a corresponding
coasting time (dependent upon the electrical network).
The generation of compressed air commences and the
electric motor cuts in, when the operating pressure has
decreased to the set minimum value.
Throttling operation
The delivery of compressed air is throttled as soon as
the pressure range set at the proportional regulator has
been reached.
7.5
Setting of the operating pressure
Danger
.
The operating pressure must be set by a specialist
only.
The operating pressure must not be set higher.
7. Commissioning
Important
Do not switch the screw compressor on repeated-
ly without having rectified the malfunction, since
this may cause considerable damage to the machi-
ne.
Re-start after an automatic shutdown due to mal-
function:
• Operate emergency shutdown
• Rectify malfunction
• Unlock emergency shutdown
• Press the [
Θ
] acknowledgement key
• The screw compressor unit can only be restarted
when the [
Θ
] acknowledgement key has been
pressed.
• Start the screw compressor unit by pressing the [ I ]
key.
Important
The operating pressure is indicated on the name-
plate (fig. 2).
A higher setting of the operating pressure is not
permitted.
It is possible to reduce the operating pressure to a
minimum of 5 bar.
The admissible maximum number of motor cycles
is controlled by the DELCOS electronics.
For systems with electronic control DELCOS 3000
and DELCOS SL, the operating pressure is set via the
electronics.
• Actuate main switch.
• Check the safety valve at operating pressure.
• For testing purposes, all LEDs and all segments on
the operating panel light up.
• Press the OFF-key for unlocking.
• Press the ON-key, the ON-key lights up >>green<<
in order to acknowledge that the screw compressor
unit is in the automatic operating mode.
7.6
Monitoring
The operating pressure and the compressor tempera-
ture can be read from the text field on the control panel.
Compressors with oil-lubricated pressure chambers
are to be operated in a manner that avoids exceeding
of the pre-set final compression temperature.
The screw compressor is equipped with an automatic
operation monitoring system, which shuts the unit down
in the case of the following malfunctions.
1 - Excessive temperature of the screw compressor
2 - Excessive temperature of the electric motor
3 - Overloading of the ventilator motor
Important
Warning : Electric voltage !
Encoders for automatic operation monitoring
must not be bridged !
The screw compressor unit must not be operated
with bridged encoders !
