VLT
®
2800 Series
Programming
Description of choice:
To be set as a percentage value of the max. DC
brake voltage, which depends on the motor.
133 Start voltage
(START VOLTAGE)
Value:
0.00 - 100.00 V
✭
Depends on unit
Function:
A higher start torque can be obtained by increasing
the start voltage. Small motors (< 1.0 kW)
normally require a high start voltage.
Description of choice:
The factory setting will be suitable for must
applications, the value may need to be increase
gradually for high torque application.
Warning: If the use of start voltage
is exaggerated, this may lead to
over-energizing and overheating of the
motor and the frequency converter may cut out.
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
Speedregulation, open
loop
[0] in parameter 100
Configuration
and
Constant
torque
[1] in parameter 101
Torque characteristic
.
Description of choice:
Key in a % value.
✭
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.28.E9.02 - VLT is a registered Danfoss trademark
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