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Table 129: Choices Depending on Control
ASM
SPM
IPM
SynRM
VVC+
Speed OL
All choices
[0],[1],[5]
[0],[1],[5]
[0],[1],[5]
Flux OL
Speed OL
[0],[1],[2],[3],[5],[6]
[0],[1],[5]
[0],[1],[5]
–
Flux CL
Speed CL
All choices
[0],[1],[5],[8]
[0],[1],[5],[8]
–
Op-
tion
Name
Description
[0]*
Coast
Leaves motor in free mode. The motor is disconnected from the drive.
[1]
DC hold
Energizes the motor with a DC hold current (see
parameter 2-00 DC Hold Current
).
[2]
Motor
check
Checks if a motor has been connected. The interval for checking the motor can be defined in
parameter
4-49 Motor Check Time Interval
.
[3]
Premagne-
tizing
Builds up a magnetic field while the motor is stopped. This allows the motor to produce torque quickly at
subsequent start commands (asynchronous motors only). This premagnetizing function does not help the
1
st
start command. Two different solutions are available to premagnetize the machine for the 1
st
start
command:
Start the drive with a 0 RPM reference and wait 2–4 rotor time constants before increasing the speed
reference.
Use the start delay with DC hold:
Set
parameter 1-71 Start Delay
to the required premagnetizing time (2–4 rotor time constants). See the
time constants description further in this section. Set
parameter 1-72 Start Function
to either
[0] DC hold
or
[1] DC Brake
. Set the DC hold or DC brake current magnitude (
parameter 2-00 DC Hold Current
or
parameter
2-01 DC Brake Current
) to be equal to I_pre-mag = Unom/(1.73 x Xh).
Sample rotor time constants = (Xh+X2)/(6.3*Freq_nom*Rr)
1 kW = 0.2 s
10 kW = 0.5 s
100 kW = 1.7 s
1000 kW = 2.5 s
[4]
DC voltage
U0
When the motor is stopped,
parameter 1-55 U/f Characteristic - U [0]
defines the voltage at 0 Hz.
[5]
Coast at
low refer-
ence
When the reference is below
parameter 1-81 Min Speed for Function at Stop [RPM]
, the drive coasts the mo-
tor.
[6]
Motor
check,
alarm
The drive issues an alarm if 1 or more motor phases are missing.
[8]
Torque
ramp to
zero
N O T I C E
This option is only available in FC 302.
When the motor reaches the speed defined in
parameter 1-81 Min Speed for Function at Stop [RPM]
, the
drive ramps the torque down to 0 torque (for example, for extruder applications where a high torque is
present at low speed). The torque ramp time can be set in
parameter 1-89 Stop Func Torque Ramp Time
.
AU275636650261en-000101 / 130R0334 | 99
Danfoss A/S © 2022.12
Parameter Descriptions
VLT AutomationDrive FC 301/302
Programming Guide