Siemens SINAMICS G130 Engineering Manual page 461

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 must be electrically dimensioned taking into account the current derating factor determined
above. This process determines the type and the number of S120 Cabinet Modules to be connected to the converter-
side deionized water circuit as well as their electrical operating data (current and power output). Based on these data
and the degree of protection, the following quantities are calculated for each S120 Cabinet Module:
- Coolant volumetric flow rate dV/dt:
This is specified in the technical data of Catalog D 21.3. This value applies regardless of the actual
capacity utilization of the S120 Cabinet Module in question because the firmware of the Chassis
power units indirectly monitors the volumetric flow rate on the basis of the temperature in the inflow
line of the deionized water circuit and the electrical operating data.
- Power loss P
This is specified in the technical data of Catalog D 21.3. The specified values depend on the
degree of protection (< IP55 or IP55) and always refer to operation at rated power P
Connection Modules and Active Line Connection Modules) or rated current I
The values can be reduced for partial-load conditions according to the following characteristics
depending on the power output or the output current:
Basic Line Connection Module
4. Calculating the total volumetric flow rate and the total power loss in the deionized water circuit
The coolant volumetric flow rates dV/dt calculated above and the power losses P
S120 Cabinet Modules must be added:
- Total volumetric flow rate dV/dt
- Total power loss P
transferred to the coolant:
L
Active Line Connection Module
:
total
∑
dV/dt = dV/dt
total
:
L total
∑
P = P
L total L
SINAMICS S120 Cabinet Modules
Engineering Information
Current derating as a function of ambient temperature
SINAMICS Engineering Manual – November 2015
(Basic Line
rated
(Motor Modules).
rated
Motor Module
transferred to the coolant of all
L
461/528
Ó Siemens AG