Siemens SINAMICS G130 Engineering Manual page 208

Fundamental Principles and System Description
Engineering Information
The chemical composition of the coolant for liquid-cooled SINAMICS S120 units must be as follows:
Units with aluminum heat sink:
Deionized water with the following properties as defined by ISO 3696 / grade 3, combined with an anti-freeze
according to the specifications on the following page:
·
pH value at 25°C
·
Electrical conductivity at 25°C
·
Components that can be oxidized as oxygen content
·
Residue after vaporization and drying at 110 °C
Units with heat sinks with an integrated stainless steel heat exchanger:
a) Deionized water with the following properties as defined by ISO 3696 / grade 3, combined with an anti-freeze
according to the specifications on the following page:
·
pH value at 25°C
·
Electrical conductivity at 25°C
·
Components that can be oxidized as oxygen content
·
Residue after vaporization and drying at 110 °C
b) Filtered drinking water or municipal water of the quality specified below:
·
pH value
·
Electrical conductivity
·
Chloride ions
·
Sulphate ions
·
Nitrate ions
·
Dissolved substances
·
Total hardness
·
Size of entrained particles
Inhibitors, anti-freeze, biocides
The following additives to the cooling water might be required depending on the heat sink material, the chemical
composition of the cooling water and the ambient conditions, as described above. With liquid-cooled SINAMICS S120
units in Chassis format, only the additives specified below may be added to the cooling water in order to ensure
correct long-term operation of the cooling circuit.
Inhibitors delay corrosive electro-chemical processes. They are an absolutely essential cooling water additive
o
for units with an aluminum heat sink and are contained in the anti-freezes specified below.
Note:
The previously recommended inhibitor NALCO® TRAC100 (former product name NALCO® 00GE056) must no
longer be used. It must be replaced by the anti-freezes listed below. These must be used in the specified
minimum concentration, even if the application does not require anti-freeze protection.
Anti-freeze prevents the coolant from freezing in minus temperatures and must always be used if the conditions
o
of use are expected to include frost. The anti-freezes specified in the table must be used in SINAMICS S120
liquid-cooled units in Chassis format. When the anti-freeze concentration is too low, it has a corrosive effect, and
when it is too high, it hinders heat dissipation. For this reason, it is essential to observe the specified minimum
and maximum concentrations. Anti-freezes contain inhibitors as standard and have a biocidal action (see table
below). It is therefore not necessary or permissible to add inhibitors or biocides to anti-freezes. It must also be
noted that the addition of anti-freeze increases the kinetic viscosity of the coolant and the pump output must be
adjusted accordingly. This applies particularly in the case of the anti-freeze Antifrogen L, which is propylene
glycol-based.
Note:
The specified anti-freezes must not be mixed with one another – not even to top up the anti-freeze level!
SINAMICS Engineering Manual – November 2015
208/528
Ó Siemens AG
5.0 to 7.5
< 5 mS/cm
< 0.4 mg/l
< 2 mg/kg
5.0 to 7.5
< 5 mS/cm
< 0.4 mg/l
< 2 mg/kg
6.5 bis 9.0
< 2000 mS/cm
< 200 mg/l
< 240 mg/l
< 50 mg/l
< 340 mg/l
< 1.7 mmol/l
< 100 mm