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3.3 Main Menu - Load and Motor - Group 1
3.3.1 1-0* General Settings
Define whether the frequency converter operates in open
loop or closed loop.
1-00 Configuration Mode
Option:
Function:
[0]
*
Open
Loop
Motor speed is determined by applying a speed
reference or by setting desired speed when in
Hand Mode.
Open Loop is also used if the frequency
converter is part of a closed loop control system
based on an external PID controller providing a
speed reference signal as output.
[3]
Closed
Loop
Motor Speed will be determined by a reference
from the built-in PID controller varying the
motor speed as part of a closed loop control
process (e.g. constant pressure or flow). The PID
controller must be configured in parameter
group 20-** or via the Function Setups accessed
by pressing the [Quick Menus] button.
NOTE
This parameter cannot be changed while the motor is
running.
NOTE
When set for Closed Loop, the commands Reversing and
Start Reversing will not reverse the direction of the motor.
1-03 Torque Characteristics
Option:
Function:
[0]
*
Compressor
torque
Compressor
[0]: For speed control of screw
and scroll compressors. Provides a voltage
which is optimized for a constant torque load
characteristic of the motor in the entire range
down to 10 Hz.
[1]
Variable
torque
Variable Torque
[1]: For speed control of
centrifugal pumps and fans. Also to be used
when controlling more than one motor from
the same frequency converter (e.g. multiple
condenser fans or cooling tower fans).
Provides a voltage which is optimized for a
squared torque load characteristic of the
motor.
[2]
Auto Energy
Optim. CT
Auto Energy Optimization Compressor
[2]: For
optimum energy efficient speed control of
screw and scroll compressors. Provides a
voltage which is optimized for a constant
torque load characteristic of the motor in the
entire range down to 15Hz but in addition
the AEO feature will adapt the voltage
exactly to the current load situation, thereby
1-03 Torque Characteristics
Option:
Function:
reducing energy consumption and audible
noise from the motor. To obtain optimal
performance, the motor power factor cos phi
must be set correctly. This value is set in
. The parameter has a
default value which is automatically adjusted
when the motor data is programmed. These
settings will typically ensure optimum motor
voltage but if the motor power factor cos phi
requires tuning, an AMA function can be
carried out using
. It is very rarely necessary
to adjust the motor power factor parameter
manually.
[3]
*
Auto Energy
Optim. VT
Auto Energy Optimization VT
[3]: For optimum
energy efficient speed control of centrifugal
pumps and fans. Provides a voltage which is
optimized for a squared torque load charac-
teristic of the motor but in addition the AEO
feature will adapt the voltage exactly to the
current load situation, thereby reducing
energy consumption and audible noise from
the motor. To obtain optimal performance,
the motor power factor cos phi must be set
correctly. This value is set in
. The parameter has a default value
and is automatically adjusted when the
motor data is programmed. These settings
will typically ensure optimum motor voltage
but if the motor power factor cos phi
requires tuning, an AMA function can be
carried out using
. It is very rarely necessary
to adjust the motor power factor parameter
manually.
NOTE
will not have effect when
= [1] PM, non salient SPM.
NOTE
For pumps or fan applications where the viscosity or
density can vary significantly or where excessive flow e.g.
due pipe breakage, can occur, it is recommended to select
Auto Energy Optim. CT
Parameter Description
VLT
®
HVAC Drive Programming Guide
36
MG.11.CC.02 - VLT
®
is a registered Danfoss trademark
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