Siemens SINAMICS S120 Equipment Manual page 176

Cooling circuit and coolant properties
8.1 Cooling circuits
Table 8-1
SINAMICS units
Heatsink material
Closed cooling circuit
Open cooling circuit
Semi-open cooling circuit
Inhibitors required
Pressure
The maximum system pressure is 600 kPa. The lowest possible pressure should be selected
to allow use of pumps with a flat characteristic.
Maximum permissible differential pressure for a heatsink: 200 kPa
The layout must be selected such that the total length of supply and drain pipe is equal for
each SINAMICS unit or motor (see Fig. 8-1).
It is not permissible to create water cooling systems with series-connected modules and/or
modules and motors as the increased volumetric flow increases the risk of cavitation and
abrasion. This type of arrangement is acceptable only if the pressure difference per unit does
not exceed 200 kPa.
Installation
The connection between the units and cooling system should be designed with hoses for
mechanical decoupling.
The following hose types are recommended:
• EPDM hoses with an electrical conductivity >10
Semperit, or
• DEMITEL made of PE / EPDM supplied by Telle
• Secured with clips conforming to DIN2817, available, e.g. from Telle, see Table 8-7.
Please note the following recommendations applicable to cooling circuit installation:
• 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 heatsink), 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 Fig. 8-3).
• To prevent blockages and corrosion, it is advisable to install an additional flushback filter
in the circuit (so that residues can be rinsed out when the system is running).
8-2
Cooling circuit for SINAMICS units
Basic Line Module,
frame sizes FBL, GBL
Active Line Modules,
frame size HXL, JXL
Motor Modules,
frame sizes HXL, JXL
Aluminium
The closed cooling circuit is the
recommended standard solution!
Not permissible!
Permissible only with inhibitors
and Antifrogen N with a
proportion X of 20 % < X ≤ 45 %.
Yes
SINAMICS S120 Equipment Manual, Edition 12/2007, 6SL3097-2AM00-0BP4
Power Modules,
frame sizes FL, GL
Active Line Modules,
frame sizes GXL
Motor Modules,
frame sizes FXL, GXL
Stainless steel
The closed cooling circuit is the
recommended standard solution!
Permissible
Permissible
Recommended
ohms (e.g. Semperflex FKD supplied by
9
Chassis Power Units Liquid Cooled