Danfoss VLT FC 100 Series Programming Manual page 52

Parameter Description
3.3.9 1-8* Stop Adjustments
1-80 Function at Stop
Option: Function:
Select the Adjustable frequency drive function
after a stop command or after the speed is
ramped down to the settings in 1-81 Min
Speed for Function at Stop [RPM].
Available selections depend on 1-10 Motor
Construction:
[0] Asynchron:
[0] coast
[1] DC hold
[2] Motor check, warning
[6] Motor check, alarm
[1] PM non-salient:
[0] coast
[0] Coast Leaves motor in free mode.
*
[1] DC Hold/ Energizes motor with a DC holding current
Motor (see 2-00 DC Hold/Preheat Current).
Preheat
[2] Motor Issues a warning if the motor is not
check, connected.
warn.
[6] Motor Issues an alarm if the motor is not connected.
check,
alarm
1-81 Min Speed for Function at Stop [RPM]
Range:
Size related [0 - 600 RPM]
*
1-82 Min Speed for Function at Stop [Hz]
Range:
Size related [ 0.0 - 20.0 Hz]
*
3.3.10 Trip at Motor Speed Low Limit
In 4-11 Motor Speed Low Limit [RPM] and 4-12 Motor Speed
Low Limit [Hz], it is possible to set a minimum speed for
the motor in order to ensure proper oil distribution.
In some cases, e.g., if operating in current limit because of
a defect in the compressor, the output motor speed can
be suppressed below Motor Speed Low Limit. To prevent
damage to the compressor, it is possible to set trip limit. If
the motor speed drops below this limit, the Adjustable
frequency drive will trip and issue an alarm (A49).
Reset will take place according to the selected function in
14-20 Reset Mode.
®
VLT HVAC Drive Programming Guide
If the trip must take place at a fairly precise speed (RPM), it
is recommended to set 0-02 Motor Speed Unit for RPM and
use slip compensation, which can be set in 1-62 Slip
Compensation.
NOTE!
To achieve the highest accuracy with the slip compen-
sation, an Automatic Motor Adaptation (AMA) should be
performed. To be enabled in 1-29 Automatic Motor
Adaptation (AMA).
NOTE!
Trip will not be active when using a normal stop or coast
command.
1-86 Trip Speed Low [RPM]
Range:
Size
related
NOTE!
This parameter is only available if 0-02 Motor Speed Unit is
set to [RPM].
1-87 Trip Speed Low [Hz]
Function:
Range:
Size
related
Function:
NOTE!
This parameter is only available if 0-02 Motor Speed Unit is
set to [Hz].
MG11CD22 - VLT ® is a registered Danfoss trademark
Function:
[ 0 - par. Set the desired motor speed for trip
4-13 RPM] limit. If the trip speed is set to 0, the
*
function is not active. If the speed at
any time after the start (or during a
stop) falls below the value in the
parameter, the adjustable frequency
drive will trip with an alarm [A49] Speed
Limit. Function at stop.
Function:
[ 0.0 - If the trip speed is set to 0, the function
par. 4-14 is not active.
*
Hz]
If the speed at any time after the start
(or during a stop) falls below the value
in the parameter, the adjustable
frequency drive will trip with an alarm
[A49] Speed Limit. Function at stop.
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