Siemens SINAMICS S120 Equipment Manual page 244

Cooling circuit, coolant properties and protection against condensation
9.1 Cooling circuits
Installation
The connection between the devices and cooling system should be designed with hoses for
mechanical decoupling.
Recommendations for the hose type, seals and clamps are provided in Chapter Materials
(Page 264).
The following information must be observed when installing the cooling circuit:
● Seals must be free of chloride, graphite and rust.
● As a result of negative experience with Teflon, Viton, AFM34 and EPDM are
recommended instead.
● In order to prevent cavitation damage to the pump (but also in the heat sink), the pressure
on the suction side of the pump must be a minimum of 30 kPa, or the geodesic height
from the reservoir to the pump suction side must be >3 m (see the diagram in Chapter
Preventing cavitation (Page 247)).
● To prevent blockages and corrosion, it is advisable also to install a flushback filter in the
circuit (so that residues can be rinsed out when the system is running). It is not
permissible that the flushback filter is bridged by a bypass circuit.
In these types of applications, automatic flashback filters have clearly proven themselves.
● For circuits with an open pressure equalization tank, oxygen and CO
water. The system should be filled for the first time with desalinated water via an ion
exchanger.
Note
Checking the hose lines
The inspection intervals depend on the prevailing ambient conditions.
The following points should be noted for the coolant hoses:
• Damage through abrasion points
• Embrittlement (e.g. forming of cracks)
• Leaks
• The hose slipping out of the coupling
• Deformations that do not comply with the natural shape of the hose (e.g. separation of
layers and blistering)
• Exceeding the storage and use times
In accordance with the accepted rules and standards, we recommend a testing cycle of
five years with the appropriate test pressure (twice the operating pressure).
244
Water-cooled chassis power units for common cooling circuits
Manual, 08/2017, 6SL3097-4AM10-0BP0
enter the cooling
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