Siemens SINAMICS S120 Equipment Manual page 263

NOTICE
Damage caused by leaks if the appropriate concentration of antifreeze is not used
An insufficient concentration of antifreeze can result in material damage caused by
corrosion and cooling circuit leaks.
• Regularly check the antifreeze concentration. Add the appropriate amount of antifreeze
NOTICE
Material damage caused by mixing different antifreeze products
Incorrectly adding antifreeze to the cooling circuit can result in material damage caused by
corrosion and cooling circuit leaks.
• Do not use different antifreeze products in a common cooling circuit.
• When changing the antifreeze, you must first empty the cooling circuit and flush it out
Biocide
Cooling circuits with soft water (°DH>4) are susceptible to microbes. The risk of corrosion
caused by microbes is virtually non-existent in chlorinated drinking water systems.
No strain of bacteria can survive when the appropriate quantity of antifreeze is added.
The following types of bacteria are encountered in practice:
● Slime-forming bacteria
● Corrosive bacteria
● Iron-depositing bacteria
The type of bacteria determines the suitability of a biocide. At least one water analysis per
annum (to determine the number of bacterial colonies) is recommended. We recommend
that a biocide is used depending on the ambient conditions – and that the compatibility with
the components in the cooling circuit is carefully checked.
Note
Determining the appropriate biocide
The type of bacteria determines the biocide.
The concentration must be adapted to be in compliance with what the manufacturer
recommends.
It is not permissible that biocides and antifreeze are mixed.
Antifreeze already has a biocidal effect in the minimum concentration specified above.
Water-cooled chassis power units for common cooling circuits
Manual, 08/2017, 6SL3097-4AM10-0BP0
Cooling circuit, coolant properties and protection against condensation
when required.
before filling the new coolant. To do this, refer to the instructions provided by the
manufacturer of the antifreeze.
9.2 Coolant definition
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