Danfoss VLT FCD 311 Design Manual page 64

Description of choice:
Set the required frequency.
140 Current, minimum value
140
(CURRENT MIN VAL)
Value:
0 % of Inom - 100 % of Inom
Function:
This is where the user selects the minimum motor
current running for the mechanical brake to be re-
leased. Current monitoring is only active from stop
until the point when the brake is released.
Description of choice:
This is an extra safety precaution, aimed at guaran-
teeing that the load is not lost during start of a lifting/
lowering operation.
142 Leakage reactance X
142
(LEAK. REACTANCE)
Value:
0.000 - XXX,XXX
Depends on choice of motor
Function:
After setting of parameters 102-106 Nameplate data,
a number of adjustments of various parameter is
made automatically , including the leakage reactance
X . The shaft performance can be improved by fine-
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tuning the leakage eactance X
NB!:
Parameter 142 The leakage reactance X
normally not to be changed if the nameplate
data have been set, parameters 102-106.
Description of choice:
X can be set as follows:
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1. The value is stated by the motor supplier.
= factory setting. () = display text [] = value for use in communication via serial communication port
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0 %
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is
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®
VLT FCD Series
2. Use the factory settings of X
quency converter itself chooses on the basis of
the motor nameplate data.
144 Gain AC brake
144
(GAIN AC BRAKE)
Value:
1.00 - 1.50
Function:
This parameter is used to set the AC brake. Using
par. 144 it is possible to adjust the size of the gener-
ator torque that can be applied to the motor without
the intermediate circuit voltage exceeding the warn-
ing level.
Description of choice:
The value is increased if a greater possible brake
torque is required. If 1.0 is selected, this corre-
sponds to the AC brake being inactive.
NB!:
If the value in par. 144 is increased, the
motor current will simultaneously increase sig-
nificantly when generator loads are applied. The
parameter should therefore only be changed if it is
guaranteed during measurement that the motor cur-
rent in all operating situations will never exceed the
maximum permitted current in the motor. Please
note: that the current cannot be read out from the
display.
146 Reset voltage vector
146
(RESET VECTOR)
Value:
*Off (OFF)
Reset (RESET)
Function:
When the voltage vector is reset it is set to the same
starting point each time a new process commences.
Description of choice:
Select reset (1) when running unique processes
each time they arise. This will enable repetitive pre-
cision when stopping to be improved. Select Off (0)
for example for lifting/lowering operations or syn-
chronous motors. It is an advantage that the motor
and the frequency converter are always synchro-
nised.
MG.04.A1.02 - VLT is a registered Danfoss trade mark
which the fre-
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1.30
[0]
[1]