VLT
®
4000 VT
Programming
403 Sleep mode timer
(SLEEP MODE TIMER)
Value:
0 - 300 sec.(OFF)
✭
OFF
Function:
This parameter enables the AFD to stop the motor
if the load on the motor is minimal. The timer in
parameter 403
Sleep mode timer
starts when the
output frequency drops below the frequency set in
parameter 404
Sleep frequency
. When the time set in
the timer has expired, the AFD will turn off the motor.
The AFD will restart the motor, when the theoretical
output frequency exceeds the frequency in
parameter 405
Wake up frequency
.
Description of choice:
Select OFF if this function is not wanted.
Set the threshold value that is to activate Sleep
mode after the output frequency has fallen below
parameter 404
Sleep frequency
.
404 Sleep frequency
(SLEEP FREQUENCY)
Value:
000,0 - par. 405
Wake up frequency
✭
0.0 Hz
Function:
When the output frequency falls below the preset value,
the timer will start the time count set in parameter 403
Sleep mode
. The present output frequency will follow
the theoretical output frequency until f
MIN
is reached.
Description of choice:
Set the required frequency.
405 Wake up frequency
(WAKEUP FREQUENCY)
Value:
Par 404
Sleep frequency -
par. 202 f
MAX
✭
50 Hz
Function:
When the theoretical output frequency exceeds the
preset value, the AFD restarts the motor.
Description of choice:
Set the required frequency.
406 Boost setpoint
(BOOST SETPOINT)
Value:
1 - 200 %
✭
100 % of setpoint
Function:
This function can only be used if
Closed loop
has
been selected in parameter 100.
In systems with constant pressure regulation, it is
advantageous to increase the pressure in the system
before the AFD stops the motor. This extends the time
during which the AFD stops the motor and helps to
avoid frequent starting and stopping of the motor, e.g.
in the case of leaks in the water supply system.
There is a fixed boost time-out on 30 sec. in case
the boost setpoint cannot be reached.
Description of choice:
Set the required
Boost setpoint
as a percentage
of the resulting reference under normal operation.
100% corresponds to the reference without
boost (supplement).
407 Switching frequency
(SWITCHING FREQ.)
Value:
Depends on the size of the unit.
Function:
The preset value determines the switching frequency of
the inverter, provided
Fixed switching frequency
[1] has
been selected in parameter 408
Interference reduction
method
. If the switching frequency is changed, this may
help to minimise possible acoustic noise from the motor.
NOTE
The output frequency of the AFD can
never assume a value higher than 1/10
of the switching frequency.
Description of choice:
When the motor is running, the switching frequency
is adjusted in parameter 407
Switching frequency
,
MG.40.A7.22 - VLT is a registered Danfoss trademark
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