Cooling Circuit Configuring Information - Siemens SINAMICS S120 Equipment Manual

8.1.4

Cooling circuit configuring information

The operating pressure must be set according to the flow conditions in the supply and return
lines of the cooling circuit. The required coolant flow rate per time unit must be set according
to the technical specifications of the devices. The units are normalized to a rated pressure of
70000 Pa (for coolant type H
If a mixture of Antifrogen N and H
calculated according to the mixing proportions. The following table specifies the pressure
drop across components at different coolant temperatures for a coolant with mixing
proportion 45 % Antifrogen N.
Table 8-3 Pressure drop at different coolant temperatures
SINAMICS units
Power Module,
frame size FL
Power Module,
frame size GL
Basic Line Module,
frame size FBL
Basic Line Module,
frame size GBL
Active Line Modules,
frame size GXL
Active Line Modules,
frame size HXL
Active Line Modules,
frame size JXL
Motor Modules,
frame size FXL
Motor Modules,
frame size GXL
Motor Modules,
frame size HXL
Motor Modules,
frame size JXL
The maximum permissible differential pressure to atmosphere in the heatsink and thus in the
cooling circuit must not exceed 6 bar. If the pump used can reach a maximum pressure in
excess of this value, appropriate measures (safety valve p ≤ 6 bar, pressure control or
similar, see Fig. 8-4) must be implemented by the customer to ensure that the maximum
pressure limit is not exceeded.
The lowest possible differential pressure between the coolant in the supply and return lines
should be selected to allow use of pumps with a flat characteristic.
The maximum differential pressure across a heatsink is 200 kPa; higher differential
pressures significantly increase the risk of cavitation and abrasion (Fig. 8-4).
Chassis Power Units Liquid Cooled
SINAMICS S120 Equipment Manual, Edition 12/2007, 6SL3097-2AM00-0BP4
O) via an orifice.
2
dV/dt H O dP H O
2 2
[l/min] [Pa]
9 70000
12 70000
9 70000
12 70000
12 70000
16 70000
27 70000
9 70000
12 70000
16 70000
27 70000
O is used as a coolant, the rated pressure must be
2
dPAntfrogen N dPAntfrogen N
45 % 0 °C 45 % 20 °C
[Pa] [Pa]
121100 97300
121100 97300
121100 97300
121100 97300
121100 97300
121100 97300
121100 97300
121100 97300
121100 97300
121100 97300
121100 97300
Cooling circuit and coolant properties
8.1 Cooling circuits
dPAntfrogen N
45 % 45 °C
[Pa]
80500
80500
80500
80500
80500
80500
80500
80500
80500
80500
80500
dPAntfrogen N
45 % 50 °C
[Pa]
78400
78400
78400
78400
78400
78400
78400
78400
78400
78400
78400
8-7