Danfoss VLT Programming Manual page 57

Parameter Description
4-58 Missing Motor Phase Function
Option:
[0] Disabled
3 3
[2] Trip 1000 ms
*
NOTE
This parameter cannot be adjusted while the motor is
running.
3.6.3 4-6* Speed Bypass
Some systems call for avoiding certain output frequencies or
speeds, due to resonance problems in the system. A
maximum of four frequency or speed ranges can be avoided.
4-60 Bypass Speed From [RPM]
Array [4]
Range:
Size related
*
4-61 Bypass Speed From [Hz]
Array [4]
Range:
Size related
*
4-62 Bypass Speed To [RPM]
Array [4]
Range:
Size related
*
4-63 Bypass Speed To [Hz]
Array [4]
Range:
Size related
*
3.6.4 Semi-Automatic Bypass Speed Set-up
The Semi-Automatic Bypass Speed Setup can be used to
facilitate the programming of the frequencies to be skipped
due to resonances in the system.
The following process is to be carried out:
1. Stop the motor.
2. Select Enabled in 4-64 Semi-Auto Bypass Set-up.
3. Press Hand On on the LCP to start the search for
frequency bands causing resonances. The motor
will ramp up according to the ramp set.
56
®
VLT
Function:
Displays an alarm in the event of a missing
motor phase.
No alarm is displayed if a missing motor phase
occurs.
Function:
[0 - par. 4-13 RPM]
Function:
[0.0 - par. 4-14 Hz]
Function:
[0 - par. 4-13 RPM]
Function:
[0.0 - par. 4-14 Hz]
MG.11.CB.02 - VLT
HVAC Drive Programming Guide
4. When sweeping through a resonance band, press
OK on the LCP when leaving the band. The actual
frequency will be stored as the first element in
4-62 Bypass Speed To [RPM] or 4-63 Bypass Speed To
[Hz] (array). Repeat this for each resonance band
identified at the ramp-up (maximum four can be
adjusted).
5. When maximum speed has been reached, the
motor will automatically begin to ramp-down.
Repeat the above procedure when speed is leaving
the resonance bands during the deceleration. The
actual frequencies registered when pressing OK will
be stored in 4-60 Bypass Speed From [RPM] or
4-61 Bypass Speed From [Hz].
6. When the motor has ramped down to stop, press
OK. The 4-64 Semi-Auto Bypass Set-up will automat-
ically reset to Off. The frequency converter will stay
in Hand mode until Off or Auto On are pressed on
the LCP.
If the frequencies for a certain resonance band are not
registered in the right order (frequency values stored in By
Pass Speed To are higher than those in By Pass Speed From) or
if they do not have the same numbers of registrations for the
By Pass From and By Pass To, all registrations will be cancelled
and the following message is displayed: Collected speed areas
overlapping or not completely determined. Press [Cancel] to
abort.
4-64 Semi-Auto Bypass Set-up
Option:
[0] Off
*
[1] Enabled Starts the Semi-Automatic Bypass set-up and
®
is a registered Danfoss trademark
Function:
No function
continue with the procedure described above.