13.4
Equipotential bonding in the cooling system
Equipotential bonding between the components in the cooling system is required (SINAMICS
S120, heat exchanger, piping, pump, etc.). This must be effected using a copper bar or
stranded copper with the appropriate conductor cross-sections to prevent the
electrochemical processes.
All cabinets must be bolted together in such a way as to ensure good conductivity (e.g.
cabinet beams directly connected to ensure a good electrical connection) to prevent potential
differences and, in turn, avoid the risk of electrochemical corrosion. As a consequence, a PE
bar must also be installed in all the cabinets, including the cooling system.
13.5
Using heat exchangers
13.5.1
Water-to-water heat exchanger
If a cooling circuit that does not exceed 35 °C but does not fulfill the cooling water
requirements is already installed in the system, the two cooling circuits can be linked via a
water-to-water heat exchanger.
The coolers for the Line Modules are attached via a distributor in such a way as to ensure
the required flow rate without exceeding the maximum permissible pressure. Conditions,
such as height differences and distances, must be taken into account here.
Figure 13-4
Booksize Power Units
Manual, (GH2), 07/2016, 6SL3097-4AC00-0BP8
Water-to-water heat exchanger
Cooling circuit and coolant properties
13.4 Equipotential bonding in the cooling system
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