Danfoss VLT 2800 Series Operating Instructions Manual page 28

Description of choice:
X can be set as follows:
L
1. The value is stated by the motor supplier.
2. Use the factory settings of X
quency converter itself chooses on the basis
of the motor nameplate data.
143 Internal fan control
(fan control)
Value:
Automatic (automatic)
Always switched on (always on)
Always switched off (always off)
Function:
This parameter can be set so that the internal fan is
automatically switched on and off. You can also set the
internal fan to be permanently switched on or off.
Description of choice:
If Automatic [0] is selected, the internal fan is switched
on or off depending on the ambient temperature and
the loading of the frequency converter.
If Always switched on [1] Always switched off [2] are
selected, the internal fan will be permanently switched
on or off.
NB!
If Always switched off [2] is selected in
combination with high switch frequency,
long motor cables or high output power,
the frequency converter's life span is re-
duced.
144 Gain AC brake
(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 generator
torque that can be applied to the motor without the in-
termediate circuit voltage exceeding the warning level.
Description of choice:
The value is increased if a greater possible brake tor-
que is required. If 1.0 is selected, this corresponds to
the AC brake being inactive.
= factory setting, () = display text, [] = value for use in communication via serial communication port
®
MG.27.A2.02 - VLT is a registered Danfoss trademark
which the fre-
L
[0]
[1]
146
[2]
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 precision
when stopping to be improved. Select Off (0) for ex-
ample for lifting/lowering operations or synchronous
motors. It is an advantage that the motor and the fre-
quency converter are always synchronized.
1.30
®
VLT 2800 Series
NB!
If the value in par. 144 is increased, the
motor current will simultaneously increase
significantly when generator loads are ap-
plied. The parameter should therefore on-
ly be changed if it is guaranteed during
measurement that the motor current 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.
Reset voltage vector
(RESET VECTOR)
[0]
[1]
27