Constant Speeds/Frequencies - ABB ACS580 Firmware Manual

Settings
• Menu - Primary settings - Ramps
• Speed reference ramping: Parameters
(pages 213 and 297).
• Torque reference ramping: Parameters 01.30,
(pages 148 and 225).
• Frequency reference ramping: Parameters 28.71... and
(pages 233 and 297).
• Jogging: Parameters
• Motor potentiometer: Parameter
• Emergency stop ("Off3" mode): Parameter
(page 214).


Constant speeds/frequencies

Constant speeds and frequencies are predefined references that can be quickly
activated, for example, through digital inputs. It is possible to define up to 7 speeds
for speed control and 7 constant frequencies for frequency control.
WARNING: Speeds and frequencies override the normal reference
irrespective of where the reference is coming from.
Settings
• Menu - Primary settings - Start, stop, reference - Constant frequencies,
Menu - Primary settings - Start, stop, reference - Constant speeds
• Parameter groups
reference chain

Critical speeds/frequencies
Critical speeds (sometimes called "skip speeds") can be predefined for applications
where it is necessary to avoid certain motor speeds or speed ranges because of, for
example, mechanical resonance problems.
The critical speeds function prevents the reference from dwelling within a critical band
for extended times. When a changing reference
a critical range, the output of the function
reference exits the range. Any instant change in the output is smoothed out by the
ramping function further in the reference chain.
When the drive is limiting the allowed output speeds/frequencies, it limits to the
absolutely lowest critical speed (critical speed low or critical frequency low) when
accelerating from standstill, unless the speed reference is over the upper critical
speed/ frequency limit.
23.20 and 23.21
22.75
22 Speed reference selection
(page 226).
23.11...23.15 and
26.18 and
(page 214).
(page 212).
23.23 Emergency stop time
(page 204) and
(22.87 Speed reference act
(22.01 Speed ref unlimited) freezes until the
Program features 97
46.01
26.19
46.02
28 Frequency
7) enters