Cooling Circuits - Siemens SINAMICS S120 Equipment Manual

Cooling circuit, coolant properties and protection against condensation

9.1 Cooling circuits

9.1 Cooling circuits
General information
A copper-nickel alloy is used to guide the coolant into the cooling plates of the water-cooled
SINAMICS S120 devices, providing the user with two options for the design of the cooling
circuit.
A common cooling circuit is possible. This includes converter, motor and system. The heat is
dissipated using a cooling system with water-water heat exchanger.
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. The materials
must be selected so that no electrical corrosion occurs (electro-chemical series of metals),
see Chapter Materials (Page 264).
Please read the following definitions for clarification:
1. Closed common cooling circuit
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. A separate
pressure-relief valve (<6 bar) must be connected to the discharge side of the pump. The
coolant is guided only through the SINAMICS devices, the heat exchange components
and possibly to a motor (for example, see Figure below). The materials used in the
cooling circuit comply with the specifications provided in Chapter Materials (Page 264).
2. Semi-open, cooling circuit
Oxygen and carbon dioxide can only enter the coolant via the pressure compensator,
otherwise the same as for 1.
The coolant is pumped through the SINAMICS devices and the heat exchanger
components, as well as through third-party components. The materials used comply with
the minimum requirements stipulated in Chapter Materials (Page 264).
It is especially important to observe the water hardness for this configuration.
Table 9- 1 Cooling circuit for SINAMICS devices
SINAMICS devices
Heat sink material
Closed cooling circuit
Semi-open cooling circuit
242
Active Line Module, frame sizes HXL, JXL
Motor Modules, frame sizes HXL, JXL
Active Interface Module, frame size JIL
Copper-nickel alloy
Permissible
Permissible
Power Modules, frame sizes FL, GL
Motor Modules, frame sizes FXL, GXL
Stainless steel
Permissible
Permissible
Water-cooled chassis power units for common cooling circuits
Manual, 08/2017, 6SL3097-4AM10-0BP0