1-56 U/f Characteristic - F
Range:
Function:
Size
related
*
[ 0 -
400.0
Hz]
Enter frequency points to manually form a U/f
characteristic matching motor. Voltage at
each point is defined in
Make a U/f characteristic based on 6 definable
voltages and frequencies, see figure below.
Simplify U/f characteristics by merging 2 or
more points (voltages and frequencies),
respectively, are set equal.
Figure 3.3
1-60 Low Speed Load Compensation
Range:
Function:
100 %
*
[0 - 199 %]
1-61 High Speed Load Compensation
Range:
Function:
100 %
*
[0 - 199 %]
1-62 Slip Compensation
Range:
Function:
0 %
*
[ -400 - 399.0 %]
1-63 Slip Compensation Time Constant
Range:
Function:
0.1 s
*
[ 0.05 - 5.00
s]
Enter the slip compensation reaction
speed. A high value results in slow
reaction, and a low value results in quick
reaction. If low-frequency resonance
problems arise, use a longer time setting.
1-66 Min. Current at Low Speed
Range:
Function:
50 %
*
[ 0 - 120 %]
1-71 Start Delay
Range:
Function:
0 s
*
[0 - 10 s] This parameter enables a delay of the starting
time. The adjustable frequency drive begins
with the start function selected in
1-71 Start Delay
Range:
Function:
. Set the start delay time until
acceleration is to begin.
1-72 Start Function
Option:
Function:
[0] DC Hold/delay
time
Motor is energized with
during start delay
time.
[2] Coast/delay time
Inverter is coasted during start delay time
(inverter off).
1-73 Flying Start
Option:
Function:
This function makes it possible to catch a motor
that is spinning freely due to a line drop-out.
Flying start will search in clockwise direction only.
If not successful, a DC brake will be activated. If PM
motor is selected, Parking will be carried out if the
speed is below 2.5%–5% of the time set in
[0] Disabled Select
[0] Disable
if this function is not required
[1] Enabled Select
[1] Enable
to enable the adjustable
frequency drive to “catch” and control a spinning
motor.
The parameter is always set to [1] Enable when
1-10 Motor Construction
= [1] PM non-salient.
Important related parameters:
•
2-01 DC Brake Current
•
2-06 DC Brake Current
•
The Flystart function used for PM motors is based on an
initial speed estimation. The speed will always be
estimated as the first thing after an active start signal is
given.
If the speed estimate comes out below 2.5%–5% of
nominal speed, then the Parking function will be engaged
(see
2-06 DC Brake Current
and
Otherwise, the adjustable frequency drive will catch the
motor at that speed and resume normal operation.
Current limitations of the Flystart Principle used for PM
motors:
•
The speed range is up to 100% Nominal Speed or
the field weakening speed (which ever is lowest).
•
Limited to power size up to 30 hp [22 kW].
Parameters
VLT
®
HVAC Basic Drive Programming Guide
MG18B222 - VLT
®
is a registered Danfoss trademark
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