ABB ACH550-UH User Manual page 130

1-126
Code Description
2605 U/f RATIO
Selects the form for the U/f (voltage to frequency) ratio below field weakening point.
1 = – Preferred for constant torque applications.
LINEAR
2 = – Preferred for centrifugal pump and fan applications. (
SQUARED
frequencies.)
2606 SWITCHING FREQ
Sets the switching frequency for the drive. Also see parameter 2607
page 1-309.
• Higher switching frequencies mean less noise.
• 12 kHz switching frequency is available in scalar control mode, that is when parameter 9904
3 ( : ). The drive nominal current rating is reduced approximately 20% with the 12 kHz setting.
SCALAR FREQ
Continuous current higher than the reduced nominal rating is not possible with this setting.
• See the availability of switching frequencies for different drive types in the table below.
208...240 V All types
380...480 V All types
500...600 V All types
2607 SWITCH FREQ CTRL
The switching frequency may be reduced if the ACH550
internal temperature rises above a limit. See the figure.
This function allows the highest possible switching
frequency to be used based on operating conditions.
Higher switching frequency results in lower acoustic noise.
0 = – The function is disabled.
OFF
1 = – The switching frequency is limited according to
ON
the figure.
2608 SLIP COMP RATIO
Sets gain for slip compensation (in %).
• A squirrel-cage motor slips under load. Increasing the frequency as the motor torque increases compensates for
the slip.
• Requires parameter 9904
0 = No slip compensation.
1...200 = Increasing slip compensation. 100% means full slip compensation.
2609 NOISE SMOOTHING
This parameter introduces a random component to the switching frequency. Noise smoothing distributes the
acoustic motor noise over a range of frequencies instead of a single tonal frequency resulting in lower peak noise
intensity. The random component has an average of 0 Hz. It is added to the switching frequency set by parameter
2606
SWITCHING FREQ
0 =
DISABLE
1 = .
ENABLE
2619 DC STABILIZER
Enables or disables the DC voltage stabilizer. The DC stabilizer is used in scalar control mode to prevent possible
voltage oscillations in the drive DC bus caused by motor load or weak supply network. In case of voltage variation
the drive tunes the frequency reference to stabilize the DC bus voltage and therefore the load torque oscillation.
0 = – Disables DC stabilizer.
DISABLE
1 = – Enables DC stabilizer.
ENABLE
2625 OVERMODULATION
Enables or disables overmodulation. Enabling overmodulation alters the drive output waveform and can increase
the RMS voltage to the motor when operating near or above motor base speed. (Field weakening area)
0 = – Disables overmodulation.
DISABLE
1 = – Enables overmodulation.
ENABLE
Parameters
Group 26: Motor Control
Range
1, 2
1, 2, 4, 8, 12 kHz
1, 2, 4 and 8 kHz
Frame sizes R1...R4 in scalar control mode
Frame sizes R1...R4 (except ACH550-01-097A-4) in scalar control mode
Frame sizes R2...R4 in scalar control mode
0, 1
0...200%
MOTOR CTRL MODE
0, 1
. This parameter has no effect if parameter 2606 = 12 kHz.
0, 1
0, 1
Resolution
1
SQUARED
-
SWITCH FREQ CTRL
12 kHz (The drive nominal current rating
is reduced approximately 20% with this setting.)
1
f
sw
limit
12 kHz
8 kHz
4 kHz
1%
= 3 ( : ).
SCALAR FREQ
1
1
1
ACH550-UH User's Manual
Default
2 ( )
SQUARED
is more silent for most operating
4 kHz
and
Motor connections
MOTOR CTRL MODE
1 ( )
ON
R1...R4 drives, see par 2606
R5...R6 drives, see par 2606
Drive
temperature
80 °C 90 °C 100 °C
0%
0 ( )
DISABLE
0 ( )
DISABLE
0 ( )
DISABLE
S
on
=
T