Example Of A Cooling Circuit Configuration - Siemens SINAMICS G130 Engineering Manual

SINAMICS S120 Cabinet Modules
Engineering Information
5. Selecting the Heat Exchanger Module
The Heat Exchanger Module must be selected on the basis of the volumetric flow rate and the power loss.
- The rated flow rate of the Heat Exchanger Module in the deionized water circuit dV/dt
must be greater than or equal to the total volumetric flow rate dV/dt
avoid tripping caused by the volumetric flow rate monitoring system implemented in the power units
of the S120 Cabinet Modules:
- The rated cooling capacity of the Heat Exchanger Module P
to the total power loss P
rise of the coolant between the inflow and return flow lines of the deionized water circuit, and in
particular to prevent the temperature from exceeding the maximum permissible return flow
temperature of 58°C when the inflow line temperatures in the deionized water circuit are high:
6. Calculating the required pressure difference between the inflow and return flow lines of the deionized
water circuit
The required pressure difference Δp between the inflow and return flow lines of the deionized water circuit depends
on the concentration of the anti-freeze:
- Δp ≥ 130 - 200 kPa (1.3 - 2.0 bar) at the minimum anti-freeze concentration
- Δp ≥ 170 - 250 kPa (1.7 - 2.5 bar) at the maximum anti-freeze concentration
The required pressure difference Δp between the inflow and return flow lines of the deionized water circuit must be
adjusted during commissioning by means of the ball valve in the inflow line of the deionized water circuit in the Heat
Exchanger Module.
7. Calculating the power loss that can be transferred from the deionized water circuit to the raw water circuit
The power loss (cooling capacity) that can be transferred from the deionized water circuit to the raw water circuit via
the heat exchanger in the Heat Exchanger Module depends on the temperature difference between the deionized
water circuit and the raw water circuit. The greater this temperature difference, the higher the power loss (cooling
capacity) that can be transferred.
The rated cooling capacity of the Heat Exchanger Module specified in the technical data of Catalog D 21.3 is based
on an inflow temperature of 45 °C in the deionized water circuit and an inflow temperature of 38 °C in the raw water
circuit. It is therefore based on a temperature difference of 7 °C and the rated flow rates in the deionized water circuit
and the raw water circuit. Since the Heat Exchanger Module has been selected above according to the volumetric
flow rate required in the deionized water circuit, and it is safe to assume that the rated flow rate in the customer's raw
water circuit can be achieved if the circuit is properly dimensioned, the power loss (cooling capacity) P
can be transferred from the deionized water circuit to the raw water circuit can be calculated from the rated cooling
capacity P of the Heat Exchanger Module selected above and from the inflow temperature in the deionized
HEM rated
water circuit T and the inflow temperature in the raw water circuit T
in deion
The power loss P
L deion raw
power loss P calculated above:
L total
7.3.4.7

Example of a cooling circuit configuration

A drive line-up built of liquid-cooled S120 Cabinet Modules requires one S120 Active Line Connection Module and
two S120 Motor Modules. It is for this drive line-up that the cooling circuit must be configured. The following
specifications and general conditions must be taken in account in the configuring process:
- Line supply voltage:
- Degree of protection of the S120 Cabinet Modules:
- Minimum ambient temperature (Plant completely OFF)
- Maximum ambient temperature in operation:
- Maximum relative air humidity in operation:
- Maximum raw water inflow temperature:
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dV/dt ≥ dV/dt
HEM deion rated total
calculated above. This is important in order to limit the temperature
L total
P ≥ P
HEM rated L total
P = P • (T
L deion raw HEM rated in deion
that can be transferred to the raw water circuit must be greater than or equal to the total
P ≥ P
L deion raw L total
HEM rated
as follows:
in raw
– T ) / 7 °C
in raw
690 V
IP55
-5 °C
40 °C
80 %
30 °C
HEM deion rated
calculated above in order to
total
must be greater than or equal
L deion raw
that