Preventing Cavitation - Siemens SINAMICS S120 Manual

The following materials can be used for the cooling system piping:
● Pipes and corrugated piping made of stainless steel (V2A or V4A steel; NIROSTA
austenite)
● Hoses made of EPDM / EPDM with an electrical resistance <10
FKD; from the Semperit company, Wimpassing - Austria)
● DEMITEL® hoses made of PE / EPDM (the Telle company, Nuremberg)
● Clamps according to DIN 2871 for fixing, available for example from the Telle company
All control cabinets must be designed with a PE busbar and a good electrical connection
must be established between them.
Note
The sealing materials must be free of chlorides, graphite, and carbon (Viton
Teflon-based seals are not permitted.
Note
When non-conductive hoses are used, particular attention must be paid to the equipotential
bonding of all the components (see Chapter Equipotential bonding in the cooling system
(Page 783)).
Note
• Check the cooling system for tightness after installation.
13.1.5

Preventing cavitation

The following applies to all cooling circuits:
● The cooling circuit must always be designed in such a way that the pressure
compensator is located on the suction side of the pump (if possible, directly at the pump).
● The minimum pressure on the suction side of the pump must be approximately 30 kPa, or
the geodesic height from the reservoir to the pump suction side must be > 3 m.
● The pressure drop across a SINAMICS device must not exceed 200 kPa in continuous
operation, otherwise the high volumetric flow can increase the risk of cavitation and/or
abrasion damage.
● The guidelines given in Chapter Cooling circuit configuration (Page 773) regarding series
connections and maximum pressure must also be followed.
Booksize Power Units
Manual, (GH2), 07/2016, 6SL3097-4AC00-0BP8
Cooling circuit and coolant properties
13.1 Cooling circuit requirements
ohms (e.g. Semperflex
9
or EPDM).
®
777