9 Additional Information
BU 0200 GB Subject to technical alterations 251
I
S
= Motor current vector
line current
I
SD
= Excitation current vector
ma
netisation current
I
SQ
= Load current vector
No flux adaptation With flux adaptation
Motor under partial load Motor under full load
9.8 Energy efficiency
NORDAC frequency inverters have very low energy requirements and are therefore very efficient. In
addition, by means of "Automatic flux adaptation" (parameter (P219)), the SK 200E provides a facility for
improving the energy efficiency of the entire drive unit (especially in applications with partial loads).
According to the torque required, the excitation current is reduced by the frequency inverter or the motor
torque to the actual level required by the drive unit. The resulting reduction in current consumption, which
may be considerable, and the optimisation of cos to 1 even in the partial load range makes a significant
contribution to energy and network optimisation.
Here, a parameterisation which deviates from the factory setting (= 100%) is only permissible for
applications which require rapid torque changes. (For details see Section 6.1.3 parameter (P219))
WARNING
This function is not suitable for lifting applications or applications with frequent or large load
changes and parameter (P219) must be left at the factory setting (100%).