Technical data

VLT
®
2800 Series
Programming
134 Load compensation
(LOAD COMPENSATIO)
Value:
0.0 - 300.0%
✭ 100.0%
Function:
In this parameter, the load characteristic is set. By
increasing the load compensation, the motor is given an
extra voltage and frequency supplement at increasing
loads. This is used e.g. in motors/applications in
which there is a big difference between the full-load
current and idle-load current of the motor.
NB!:
If this value is set too high, the frequency
converter may cut out because of overcurrent.
Description of choice:
If the factory setting is not adequate, load
compensation must be set to enable the motor
to start at the given load.
Warning: Should be set to 0% in
connection with synchronous and
parallel-coupled motors and in the
case of quick load changes. Too high load
compensation may lead to instability.
135 U/f-ratio
(U/F RATIO)
Value:
0.00 - 20.00 at Hz
✭ Depends on unit
Function:
This parameter enables a shift in the ratio between
output voltage (U) and output frequency (f) linearly,
so as to ensure correct energizing of the motor and
thus optimum dynamics, accuracy and efficiency.
The U/f-ratio only affects the voltage characteristic
if a selection has been made of Constant torque
[1] parameter 101 Torque characteristic.
Description of choice:
The U/f-ratio is only to be changed if it is not
possible to set the correct motor data in parameter
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 selection has been made of Speedreg ulation, open
loop [0] in parameter 100 Configuration and Constant
torque [1] in parameter 101 Torque c haracteristic.
Description of choice:
Key in a % value.
137 DC hold voltage
(DCHOLDVOLTAGE)
Value:
0 - 100% of max. DC hold voltage
✭ 0%
Function:
This parameter is used to keep the motor
(holding torque) 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
function or 122 Function at stop .Tobesetas
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:
Here you can select the frequency at which the external
brake is released, via the output defined in parameter
323 Relay output 1-3 or 341 Digital output, terminal 46.
Description of choice:
Set the required frequency.
✭ = factory setting. () = display text [] = value for use in communication via serial communication port
MG.28.A9.02 - VLT is a registered Danfoss trademark
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