VLT
®
8000 AQUA
the process regulation. This can be an advantage
if there is a lot of noise on the signal.
Used in
Closed loop
[1] (parameter 100).
Description of choice:
Select the desired time constant (
τ
). If a time constant
(
τ
) of 0.1 s is programmed, the break frequency
for the lowpass filter will be 1/0.1 = 10 RAD/sec.,
corresponding to (10/(2 x
π
)) = 1.6 Hz.
The process regulator will thus only regulate a feedback
signal that varies by a frequency lower than 1.6 Hz.
If the feedback signal varies by a higher frequency
than 1.6 Hz, the Process regulator will not react.
433 Motor Alternation Time
(MOTOR ALT. TIME)
Value:
0 (OFF) - 999 hrs
✭
OFF
Function:
This is the time that sets the length of time between
motor alternation events. When the time elapses,
the relay selected in parameter 323 or 326 changes
state and initiates the external control devices that
disconnect the active motor and connect the alternate
motor. (Contactors or Starters used to connect and
disconnect the motors are supplied by others.)
The timer resets after completition of the
alteration sequence.
Parameter 434 - Motor Alteration Function, selects
the type of stop - Ramp or Coast.
Description of choice:
Sets the time between motor alternation events.
434 Motor Alteration Function
(MOTOR ALT. FUNCTION)
Value:
✭
Ramp (RAMP)
[0]
Coast (COAST)
[1]
Function:
When a motor is stopped after the duration set in
parameter 433,
Motor alternation time
expires, the
motor is commanded to either coast or ramp to
a stop. If the motor is not running at the time of
alteration, the relay simply changes state. If the motor
is running at the time of alteration, a start command is
sent following alteration. Motor Alteration is displayed
on the drive control panel during alternation.
When
Coast
is selected, after coasting is initiated, a
delay of 2 seconds occurs prior to the relay changing
state. Ramp-down time is set in parameter 207.
Description of choice:
Set the desired stop function.
483 Dynamic DC link compensation
(DC LINK COMP.)
Value:
Off
[0]
✭
On
[1]
Function:
The AFD includes a feature, which ensures that
the output voltage is independent of any voltage
fluctuation in the DC link, e.g. caused by fast
fluctuation in the line supply voltage. The benefit
is a very steady torque on motor shaft (low torque
ripple) under most line conditions.
✭
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.80.A7.22 - VLT is a registered Danfoss trademark
140
Rosewood STP ST42 General (Operation and Maintenance Manual - Part 4:
Section 6.3 Manufacturers Manuals 6.3.33 Danfoss VLT Aquadrive 8000) Vendor Manual
QP Id: VM207
Active: 03/09/2013
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