Baumuller b maXX 3000 - Frequency-Output-Dependent Current Derating; Derating at a Static Inverter Frequency < 15 Hz

Electrical data
Instruction handbook b maXX BM3000, BM3200, BM3300
Document no. 5.11018.11 Baumüller Nürnberg GmbH
44
of 218
3.4
3.4.6 Frequency-output-dependent current derating
All Baumüller devices were developed, so that the specified rated-output current is per-
manently permitted, i. e. in the S1-operation, at an electrical output frequency of more
than 15 Hz. If the statical output frequency of the inverter is smaller than 15 Hz and the
frequency is longer than 5 seconds between 0 and 15 Hz, then the permitted, permanent
output current must be reduced, conforming to the following characteristic curve.
Among others, in the following a few examples are shown:
n applications with speed control without positioning or
n applications, where at standstill current must be applied in order to maintain a torque /
a force or
n applications, which cause a blocking of the mechanics, e. g. when starting a cold 
extruder.
Consequently the following operations are not concerned:
n typical positioning operations
n applications, where a higher-level control contains a standstill and block monitoring.
As long as the derating range is passed fast enough, the use of I
rated
is permitted. Passing
fast enough, means that the frequency change is 15 Hz/s.
Derating of the motor-side inverter-output current I against the rating-output current 
I
rated
, in dependence on the static inverter-output frequency f.
Static inverter-output frequency f
Figure 13: Derating at a static inverter frequency < 15 Hz
I
I
rated