Siemens S120 - Derating as a Function of the Ambient Temperature, Pulse Frequency, and Installation Altitude

System overview
2.6 Derating as a function of the ambient temperature, pulse frequency, and installation altitude
AC Drive
Manual, (GH6), 04/2014, 6SL3097-4AL00-0BP4
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2.6
Derating as a function of the ambient temperature, pulse frequency,
and installation altitude
Preliminary remark
The air pressure and therefore the air density drop at altitudes above sea level. At these
altitudes, the same quantity of air does not have the same cooling effect and the air gap
between two electrical conductors can only insulate a lower voltage. Typical values for air
pressure are summarized in the table below:
Table 2- 4 Air pressure for various installation altitudes
Installation altitude above
sea level in [m]
0 1000 2000 3000 4000
Air pressure in mbar [kPa]
100
90
80
70
62
Derating
The Power Modules are designed for operation under the following conditions:
● Ambient temperature 0° C up to 40° C
● The pulse frequency specified for each Power Module
● Installation altitude of up to 1000 m above MSL for Blocksize Power Modules.
● Up to 2000 m above MSL for Chassis Power Modules.
If you operate the Power Modules at higher ambient temperatures, pulse frequencies, or
installation altitudes, you must reduce the output current.
You will find the reduction factors for the individual units in the technical data of the relevant
Power Modules.
The maximum permissible ambient temperature for all Power Modules is 55° C.
A TN or TT system with grounded neutral point is required (no grounded phase conductor)
for installation altitudes above 2000 m. If the neutral point is not grounded, an isolating
transformer must be connected upstream for which the secondary windings are grounded at
the neutral point.
A reduction of the line supply voltage phase-phase is not necessary.