Cooling Circuits - Siemens SINAMICS S120 Equipment Manual

Cooling circuit and coolant properties

8.1 Cooling circuits

8.1 Cooling circuits
General information
The type of heat sink materials used requires two distinctly different heat exchange
concepts.
Different materials are used to guide the coolant into the cooling plates of the SINAMICS
S120 Liquid Cooled units, providing the user with a range of different options for the design
of the cooling circuit.
The electrochemical processes that take place in a cooling system must be minimized by
choosing the right materials. For this reason, mixed installations (i.e. a combination of
different materials, such as copper, brass, iron, or halogenated plastic (PVC hoses and
seals)) should not be used or limited to the absolutely essential minimum.
Please read the following definitions for clarification:
1. Closed cooling circuit
2. Open cooling circuit
3. Semi-open cooling circuit
Table 8- 1 Cooling circuit for SINAMICS units
SINAMICS units
Heat sink material
Closed cooling circuit
Open cooling circuit
Semi-open cooling circuit
Inhibitors required
226
The pressure compensator is closed (no ingress of oxygen) and is fitted with a pressure-
relief valve (6 bar); it is always connected on the suction side of the pump! The coolant is
guided only through the SINAMICS units, the heat exchange components and possibly to
a motor (for example, see Figure below). The materials used in the cooling circuit comply
with the recommendations in the "Materials" section.
The coolant is guided through the SINAMICS units and the heat exchange components,
as well as through components external to the cooling circuit. The materials used comply
with the minimum requirements stipulated in Section "Materials".
Oxygen can be transferred to the coolant only via the pressure compensator, otherwise
as for 1.
Basic Line Module, frame sizes FBL, GBL
Active Line Module, frame sizes HXL, JXL
Motor Modules, frame sizes HXL, JXL
Aluminum
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
Power Modules, frame sizes FL, GL
Active Line Module, frame size GXL
Motor Modules, frame sizes FXL, GXL
Stainless steel
The closed cooling circuit is the
recommended standard solution!
Permissible
Permissible
Recommended
Chassis Liquid Cooled Power Units
Manual, (GH7), 01/2011, 6SL3097-4AM00-0BP1