Siemens SINAMICS G130 Engineering Manual page 463

1. Calculating the required coolant temperature setpoint in the inflow line of the deionized water circuit
At the maximum ambient temperature of 40 °C and the maximum relative air humidity of 80 % specified for this
example, the dew point is 35.8 °C according to the table.
Ambient
temperature
20 %
T
10 °C < 0 °C
20 °C < 0 °C
25 °C 0.6 °C
30 °C 4.7 °C
35 °C 8.7 °C
40 °C 12.8°C
45 °C 16.8°C
50 °C 20.8°C
On this basis, it is possible to calculate the minimum coolant temperature setpoint T
deionized water circuit as follows:
The calculated coolant temperature setpoint T
control system of the Heat Exchanger Module during commissioning. The control system uses the 3-way valve
(bypass valve) in the deionized water circuit of the Heat Exchanger Module to keep the setpoint constant.
2. Calculating the current derating factor of the power units required by the temperature conditions
The maximum ambient temperature T
of 40 °C in the inflow line of the deionized water circuit calculated above are within the permissible range of the
relevant current derating characteristics taking into account the IP55 degree of protection. Therefore no current
derating has to be applied to the S120 power units.
Current derating as a function of the inflow coolant
temperature of the converter-side deionized water circuit
for degrees of protection < IP55 and IP55
3. Dimensioning and selection of all S120 Cabinet Modules in the drive line-up
The entire drive line-up is electrically dimensioned without taking into account current derating factors required by
temperature as described above. For the cooling circuit configuring example given here, it has been assumed that
the following S120 Cabinet Modules would be selected in degree of protection IP55 including the relevant loads:
• One Active Line Connection Module:
• Two Motor Modules:
The volumetric flow rate and the dissipated heat loss are calculated for each of these S120 Cabinet Modules:
30 % 40 % 50 %
< 0 °C < 0 °C 0.2 °C
2.0 °C 6.0 °C 9.3 °C
6.3 °C 10.5°C 13.8°C
10.5°C 14.9°C 18.4°C
14.8°C 19.3°C 22.9°C
19.1°C 23.7°C 27.5°C
23.3°C 28.2°C 32.0°C
27.5°C 32.6°C 36.6°C
T = T (T and Φ according to table) + 4 °C = 35.8 °C + 4 °C ≈ 40 °C
set dp max max
in the inflow line of the deionized water circuit must be set on the
set
of 40 °C specified for this example and the coolant temperature setpoint T
max
SINAMICS S120 Cabinet Modules
Relative air humidity Φ
60 % 70 % 80 %
2.7 °C 4.8 °C 6.7 °C
12.0°C 14.3°C 16.4°C
16.7°C 19.1°C 21.2°C
21.3°C 23.8°C 26.1°C
26.0°C 28.6°C 30.9°C
30.6°C 33.4°C 35.8°C
35.3°C 38.1°C 40.6°C
40.0°C 42.9°C 45.5°C
Current derating as a function of ambient temperature
690 V / 1700 kW / 1560 A / 100 % load
690 V / 1000 kW / 1025 A / 85 % load
SINAMICS Engineering Manual – November 2015
Engineering Information
85 % 90 % 95 %
7.6 °C 8.4 °C 9.2 °C
17.4°C 18.3°C 19.1°C
22.2°C 23.2°C 24.1°C
27.1°C 28.1°C 29.0°C
32.0°C 33.0°C 34.0°C
36.9°C 37.9°C 38.9°C
41.8°C 42.9°C 43.9°C
46.6°C 47.8°C 48.9°C
in the inflow line of the
set
463/528
Ó Siemens AG
100 %
10.0°C
20.0°C
24.9°C
29.9°C
34.9°C
39.9°C
44.9°C
49.9°C
set