ABB ACS850-04 series, Firmware Manual

Page: 59 / 296

Program features 59
The drive is capable of determining the rotor position when started to a running motor
in open-loop or closed-loop modes. In this situation, the setting of
11.07 Autophasing
mode has no effect.
Constant speeds
It is possible to predefine up to 7 constant speeds. Constant speeds can be activated,
for example, through digital inputs. Constant speeds override the speed reference.
Settings
Parameter group 26 Constant speeds (page 168 ).
Critical speeds
A Critical speeds function is available for applications where it is necessary to avoid
certain motor speeds or speed ranges because of, for example, mechanical
resonance problems.
Settings
Parameter group 25 Critical speed (page 167 ).
DC voltage control
„
Overvoltage control
Overvoltage control of the intermediate DC link is needed with two-quadrant line-side
converters when the motor operates within the generating quadrant. To prevent the
DC voltage from exceeding the overvoltage control limit, the overvoltage controller
automatically decreases the generating torque when the limit is reached.
ș
Absolute encoder/resolver
Rotor
N
S