Siemens SINAMICS DCM Manual page 548

10.21 Speed-dependent current limitation
Speed-dependent current limitation protects the DC motor's commutator and brushes at high
speeds.
The settings required for this (p50104 to p50107) must be taken from the motor rating plate.
Additionally, the maximum operating speed of the motor (p50108) must be entered; this must
match the actual maximum operating speed.
The actual maximum operating speed is determined as follows:
● Using p2000 in cases where the actual speed value comes from an incremental encoder
● Using p50741 in cases where the actual speed value comes from an analog tachometer
● Using p50115 in the case of operation without a tachometer
Aside from this, speed-dependent current limitation must be activated by setting p50109 to 1.
NOTICE
Making an incorrect setting for speed-dependent current limitation can lead to excessive
stress on the commutator and brushes, which in turn results in a significantly reduced
service life for the brushes.
SINAMICS DCM DC Converter
Operating Instructions, 02.2015, A5E34763375/RS-AA/001
ac.maher.co.ir
Descriptions of functions
10.21 Speed-dependent current limitation
549