User-Definable Load Curve - ABB ACS850 Manual

66 Program features
IR compensation for a scalar controlled drive
IR compensation is active only when
the motor control mode is scalar. When
IR compensation is activated, the drive
gives an extra voltage boost to the
motor at low speeds. IR compensation
is useful in applications that require a
high break-away torque.
In Direct Torque Control (DTC), no IR
compensation is possible or needed.

User-definable load curve

The drive output can be limited by defining a user-definable load curve. In practice,
the user load curve consists of an overload and an underload curve, even though
neither is compulsory. Each curve is formed by five points that represent output
current or torque as a function of frequency.
An alarm or fault can be set up to occur when the curve is exceeded. The upper
boundary (overload curve) can also be used as a torque or current limiter.
Load (%)
34.13
34.08
Par. 34.03
Settings
Parameter group 34 User load curve
34.14
Allowed operating range
34.09
Par. 34.04 Par.
(page 204).
Motor Voltage
IR Compensation
No compensation
Overload area
34.15
34.16
34.11
34.10
Underload area
34.05 Par. 34.06
f (Hz)
34.17
34.12
f (Hz )
Par. 34.07