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Operating Instructions – MOVIDRIVE® MDR60A/61B
10
General information
Safety Notes (MDR60A1320-503-00)
10.1.3 Operation with a transformer
If only a few consumers operate in a power supply section besides the regenerative
power unit, the transformer must be able to transmit the power not used in this section
to the next voltage level without the voltage becoming excessively high in the section.
This means the rated (apparent) power of the transformer must be at least 1.5 times
greater than the (effective) power regenerated from this section to also transmit the har-
monics and reactive components of the currents.
These conditions are met in the power supply section shown in following figure when all
other consumers are turned off. If the regenerated power is close to the rated power of
the transformer, the u
K
value of the transformer must be sufficiently small (max. 6 %) to
limit the voltage increase in the power supply section.
Operation of MOVIDRIVE
®
-MDR60A1320-503-00 units in connection with variable
transformers with a large u
K
of 10 - 20 % (e.g. in a design as stalled slipring motor) is
permitted only if the ratio regenerative power/rated power is considerably smaller.
1877085451
M
M
R
Tr
10kV
0,4kV
100kVA
60kW
20kW
20kW
MOVIDRIVE
MDR
®
