KB-120-8
30
WARNING
Induction, electric voltage!
Never operate the motor with the terminal box
open!
When the rotor rotates, electric voltage is induced in
the terminal pins – even with the motor switched off.
Permitted work on a compressor with LSPM motor
Work on the electric connection and screwed connec-
tions in the terminal box, oil change as well as inspec-
tion and replacement of pressure relief valves, cylinder
banks and sight glass. No special tools are needed for
this work. Before opening the compressor, thoroughly
clean its environment. Pay special attention to loose
metal particles! Do not open the motor cover!
6
Commissioning
Information
General information and requirements, see op-
erating instructions KB-104.
Before commissioning the system, check all safety and
monitoring devices of the system and in the machine
room for correct functioning.
The following information must also be available:
• Design parameters.
• Maximum allowable pressures at standstill and dur-
ing operation.
• Pipelines and instruments diagram.
Information
Special care is required when commissioning
CO
2
cascade systems.
Due to the high solubility of refrigerant in oil, the
high pressure levels and possibly strong pres-
sure variations after the starting process, there
is a risk of overstress and lack of lubrication.
It is therefore necessary to observe thoroughly
the working behaviour and the operating condi-
tions and to switch off the compressor(s) tem-
porarily in case of abnormal conditions.
Supervise the system during the whole commis-
sioning process!
6.1
Evacuation
• Switch on the oil heater.
Information
For applications with CO
2
, the "standing va-
cuum" should reach a value of 0.67 mbar
(500 microns) before the commissioning.
During the evacuation process, break the va-
cuum several times with dry nitrogen.
6.2
Charging with refrigerant
The following chapter describes general requirements
when charging with refrigerant and when commission-
ing the compressors of a cascade system. Depending
on the design and the control of the system, some ad-
aptations may be necessary. For commissioning of a
CO
2
booster system, see KB-130.
DANGER
Liquid CO
2
evaporates quickly, cools down at
the same time and forms dry ice!
Danger of cold burns and frost bites!
Avoid uncontrolled deflating of CO
2
!
When filling the system with CO
2
, wear gloves
and goggles!
• When extracting CO
2
out of a bottle without ascend-
ing pipe, use a pressure reducer! In general, also
after service work, always break the vacuum with
gaseous CO
2
.
• For CO
2
bottles with ascending pipe, only extract
high-pressure liquid! Do not use a pressure reducer!
The membranes of the pressure reducers are not
completely sealed against liquid penetration.
After filling the system with liquid, remove filling
pipeline or filling hose and make sure that no liquid is
enclosed in it any more!
Information
CO2 cascade systems are normally used in
combination with a refrigeration system for me-
dium temperature applications. When commis-
sioning the CO
2
system, this system should
already be in operation and have reached stable
operating conditions.
Due to the high requirements regarding residual
moisture, a filter drier is required when charging
with CO
2
!
