Danfoss VLT 2800 Design Manual page 72

Programming
Complete AMT:
AMT is completed by giving a RESET signal. Parameter 108
Stator resistance, Rs is updated with the optimised value.
Interrupting AMT:
AMT can be interrupted during the optimisation procedure
by giving a STOP signal.
When using the AMT function the following points should
be observed:
4 4
•
For AMT to be able to define the motor
parameters as well as possible, enter the correct
name plate data for the motor connected to the
frequency converter in parameters 102 to 106.
•
Alarms appear in the display if faults arise during
tuning of the motor.
•
As a rule the AMT function is able to measure the
R values for motors that are 1-2 times larger or
S
smaller than the frequency converter's nominal
size.
•
Press the [STOP/RESET] key to interrupt automatic
motor tuning.
Description of choice:
Select [2] Optimisation on to perform automatic motor
tuning.
NOTICE
AMT is not possible on VLT 2880-82.
WARNING
Do not perform AMT on motors connected in parallel. Do
not make set-up changes while AMT is running. There is
a risk of equipment damage and personal injury.
108 Stator resistance R
Value:
0.000 - X.XXX Ω
Function:
After setting of parameters 102-106 Nameplate data, a
number of adjustments of various parameters is carried out
automatically, including stator resistance R
entered R must apply to a cold motor. The shaft
S
performance can be improved by fine-tuning R
see procedure below.
Description of choice:
R can be set as follows:
S
1. Use the factory settings of R
frequency converter selects on the basis of the
motor nameplate data.
2. The value is stated by the motor supplier.
3. The value is obtained through manual
measurements: R
70
Design Guide
S
Depends on choice of motor
. A manually
S
and X ,
S S
which the
S
can be calculated by
S
Danfoss A/S © Rev. May/2014 All rights reserved.
measuring the resistance R
phase terminals. Where R
1-2 Ohms (typical for motors > 5.5 kW, 400 V), a
special Ohm-meter should be used (Thomson-
bridge or similar). R
S
4. R is set automatically when AMT has been
S
completed. See parameter 107 Auto motor
adaption.
NOTICE
Parameters 108 Stator resistance R
reactance X are normally not to be changed if
S
nameplate data has been set.
109 Stator reactance X
Value:
0.00 - X,XX Ω
Function:
After setting of parameters 102-106 Nameplate data, a
number of adjustments of various parameters are made
automatically, including stator reactance X
performance can be improved by fine-tuning R
see procedure below.
Description of choice:
X can be set as follows:
S
1. The value is stated by the motor supplier.
2. The value is obtained through manual
measurements X is obtained by connecting a
S
motor to mains and measuring the phase-phase
voltage U and the idle current
M
U
M
X
= −
s
3 × I
ϕ
X : See parameter 142.
L
3. Use the factory settings of X
frequency converter selects on the basis of the
motor nameplate data.
117 Resonance damping
Value:
OFF - 100%
OFF %
Function:
It is possible to optimise the resonance damping in CT
mode. The grade of the influence is adjusted in this
parameter.
The value may be set between 0% (OFF) and 100%. 100%
corresponds to 50% reduction of U/F ratio.
Default value is OFF.
Internal settings (fixed):
The resonance filter is active from 10% of nominal speed
and above.
In this case 5Hz and above.
Speed to go from 0 to nominal flux level: 500ms
between 2
PHASE-PHASE
is lower than
PHASE-PHASE
= 0.5 x R .
PHASE-PHASE
and 109 Stator
S
S
Depends on choice of motor
. The shaft
S
and X ,
S S
.
φ
X
L
2
which the
S
[OFF - 100]
[OFF]
MG27E402