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135
U/f-ratio
(U/f RATIO)
Value:
0.00 - 20.00 at Hz
Depends on unit
Function:
This parameter enables a linear shift in the ratio be-
tween output voltage (V) and output frequency (f) to
ensure correct energizing of the motor and thus opti-
mum dynamics, accuracy and efficiency. The V/f-ratio
only affects the voltage characteristic if
Constant tor-
que
[1] has been selected in parameter 101
Torque
characteristic
.
Description of choice:
Change the V/f-ratio only if it is not possible to set the
correct motor data in parameters 102-109. The value
programmed in the factory settings is based on idle
operation.
136
Slip compensation
(SLIP COMP.)
Value:
-500 - +500% of rated slip compensation
100%
Function:
Slip compensation is calculated automatically, on the
basis of such data as the rated motor speed n
M,N
. In
this parameter, the slip compensation can be fine-
tuned, thereby compensating for tolerances on the
value for n
M,N
. Slip compensation is only active if a se-
lection has been made of
Speedregulation, open
loop
[0] in parameter 100
Configuration
and
Constant
torque
[1] in parameter 101
Torque characteristic
.
Description of choice:
Key in a % value.
137
DC hold voltage
(DC HOLD VOLTAGE)
Value:
0 - 100% of max. DC hold voltage
0%
Function:
This parameter is used to keep the motor (holding tor-
que) at start/stop.
Description of choice:
This parameter can only be used if a selection has
been made of
DC hold
in parameter 121
Start func-
tion
or 122
Function at stop
. To be set as a percentage
value of the max. DC hold voltage, which depends on
the choice of motor.
138
Brake cut out value
(Brake cut out)
Value:
0.5 - 132.0/1000.0 Hz
3.0 Hz
Function:
Select the frequency at which the external brake is re-
leased, via the output defined in parameter 323
Relay
output 1-3
or 341
Digital output, terminal 46
.
Description of choice:
Set the required frequency.
139
Brake cut in frequency
(Brake cut in)
Value:
0.5 - 132.0/1000.0 Hz
3.0 Hz
Function:
Select the frequency at which the external brake is ac-
tivated; this takes place via the output defined in pa-
rameter 323
Relay output 1-3
or 341
Digital output
terminal 46
.
Description of choice:
Set the required frequency.
140
Current, minimum value
(CURRENT MIN VAL)
Value:
0 % - 100 % of inverter output current
0 %
VLT
®
2800 Series
= factory setting, () = display text, [] = value for use in communication via serial communication port
MG.27.A2.22 - VLT
®
is a registered Danfoss trademark
49
Prog
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