Danfoss VLT Series Programming Manual page 47

Parameter Description
1-77 Compressor Start Max Speed [rpm]
Range:
3 3
NOTE
1-77 Compressor Start Max Speed [RPM] will not have effect
when 1-10 Motor Construction = [1] PM, non salient SPM.
1-78 Compressor Start Max Speed [Hz]
Range:
Size [ 0.0
related - par.
*
4-14
Hz]
NOTE
1-78 Compressor Start Max Speed [Hz] will not have effect
when 1-10 Motor Construction = [1] PM, non salient SPM.
46
VLT
Function:
This function allows high starting torque and
use of a fast starting ramp. To ensure the
build-up of a high torque during the start,
various tricks can be done through clever use
of start delay / start speed / start current.
Function:
The parameter enables "High Starting
Torque". This is a function, where the Current
Limit and Torque Limit are ignored during
start of the motor. The time, from the start
signal is given until the speed exceeds the
speed set in this parameter, becomes a "start-
zone" where the current limit and motoric
torque limit is set to what is maximum
possible for the drive/motor combination. This
parameter is normally set to the same value
as 4-11 Motor Speed Low Limit [RPM]. When
set to zero the function is inactive.
In this "starting-zone" 3-82 Starting Ramp Up
Time is active instead of 3-41 Ramp 1 Ramp
Up Time to ensure extra acceleration during
the start and to minimize the time where the
motor is operated under the minimum speed
for the application. The time without
protection from the Current Limit and Torque
Limit must not exceed the value set in
1-79 Compressor Start Max Time to Trip or the
drive will trip with an alarm [A18] Start Failed.
When this function is activated to get a fast
start then also1-86 Trip Speed Low [RPM] is
activated to protect the application from
running below minimum motor speed e.g.
when in current limit.
This function allows high starting torque and
use of a fast starting ramp. To ensure the
build-up of a high torque during the start,
various tricks can be done through clever use
of start delay / start speed / start current.
MG.11.CC.02 - VLT
®
HVAC Drive Programming Guide
1-79 Compressor Start Max Time to Trip
Range:
5.0 s [0.0 -
*
10.0 s]
NOTE
1-79 Compressor Start Max Time to Trip will not have effect
when 1-10 Motor Construction = [1] PM, non salient SPM.
3.3.8 1-8* Stop Adjustments
1-80 Function at Stop
Option:
[0] Coast
*
[1] DC Hold/
Motor
Preheat
[2] Motor
check,
warning
[6] Motor
check, alarm
1-81 Min Speed for Function at Stop [RPM]
Range:
Size related
*
1-82 Min Speed for Function at Stop [Hz]
Range:
Size related
*
®
is a registered Danfoss trademark
Function:
The time, from the start signal is given until
the speed exceeds the speed set in
1-77 Compressor Start Max Speed [RPM] must
not exceed the time set in the parameter or
the drive will trip with an alarm [A18] Start
Failed.
Any time set in 1-71 Start Delay for use of a
start function must be executed within the
time limit.
Function:
Select the frequency converter 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
Leaves motor in free mode.
Energizes motor with a DC holding current
(see 2-00 DC Hold/Preheat Current).
Issues a warning if the motor is not
connected.
Issues an alarm if the motor is not connected.
Function:
[0 - 600 RPM] Set the speed at which to activate
1-80 Function at Stop.
Function:
[ 0.0 - 20.0 Hz] Set the output frequency at which
to activate 1-80 Function at Stop.