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Option Name Description
[0]*
Off
C A U T I O N
RISK OF MOTOR DAMAGE
Using this option may lead to motor damage.
The drive does not issue a missing motor phase alarm.
[1]
On
Before each start, the drive checks if all 3 motor phases are present. The check is performed without any shaft
movement. The function also enables 3-phase detection in U/f and VVC+ mode. See description in
parameter
4-58 Missing Motor Phase Function
.
The table details the motor check at start for different motor control principles.
Table 301: Motor Check at Start for Different Motor Control Principles
Option Motor Check
at Start
U/f
VVC
+
Flux
open
loop
Flux
closed
loop
[0]
Off
No function.
[1]
On
Check for missing motor phase before start is executed and enables
3-phase detection for U/f and VVC+ in
parameter 4-58 Missing Motor
Phase Function
.
5.5.6 4-6* Speed Bypass
Some systems require that certain output frequencies or speeds are avoided due to resonance problems in the system. A maximum
of 4 frequency or speed ranges can be avoided.
Parameter 4-60 Bypass Speed From [RPM]
Table 302: Parameter 4-60 Bypass Speed From [RPM]
4-60 Bypass Speed From [RPM]
Default value: Size related
Parameter type: Range, 0 - setting in par. 4-13 RPM, Array [4]
Setup: All setups
Conversion index: 67
Data type: Uint16
Change during operation: True
Some systems call for avoiding certain output speeds due to resonance problems in the system. Enter the lower limits of the speeds
to be avoided.
Parameter 4-61 Bypass Speed From [Hz]
Table 303: Parameter 4-61 Bypass Speed From [Hz]
4-61 Bypass Speed From [Hz]
Default value: Size related
Parameter type: Range, 0 - setting in par. 4-14 Hz, Array [4]
Setup: All setups
Conversion index: -1
Data type: Uint16
Change during operation: True
Some systems require that certain output frequencies or speeds are avoided due to resonance problems in the system. Enter the
lower limits of the speeds to be avoided.
Parameter 4-62 Bypass Speed To [RPM]
Table 304: Parameter 4-62 Bypass Speed To [RPM]
4-62 Bypass Speed To [RPM]
Default value: Size related
Parameter type: Range, 0 - setting in par. 4-13 RPM, Array [4]
Setup: All setups
Conversion index: 67
Data type: Uint16]
Change during operation: True
AU275636650261en-000101 / 130R0334
168 | Danfoss A/S © 2022.12
Parameter Descriptions
VLT AutomationDrive FC 301/302
Programming Guide