Danfoss VT2800 Series Design Manual page 72

Description of choice:
Set the necessary time for which a high
start torque is required.
120 Start delay
(START DELAY)
Value:
0.0 - 10.0 sec.
Function:
This parameter enables a delay of the start-up time
after the conditions for start have been fulfilled.
When the time has passed, the output frequency
will start by ramping up to the reference.
Description of choice:
Set the necessary time before commencing
to accelerate.
121 Start function
(START FUNCTION)
Value:
DC hold during start delay time
(DC HOLD/DELAY TIME)
DC brake during start delay time
(DC BRAKE/DELAY TIME)
Coasting during start delay time
(COAST/DELAY TIME)
Start frequency/voltage clockwise
(CLOCKWISE OPERATION)
Start frequency/voltage in reference direction
(VERTICAL OPERATION)
Function:
This is where to choose the required mode during the
start delay time (parameter 120 Start delay time).
Description of choice:
Select DC hold during start delay time [0] to energize
the motor with a DC hold voltage during the start delay
time. Set voltage in parameter 137 DC hold voltage.
Choose DC brake during start delay time [1] to energize
the motor with a DC brake voltage during the start delay
time. Set voltage in parameter 132 DC brake voltage.
Choose Coasting during start delay time [2] and the
motor will not be controlled by the frequency converter
during the start delay time (inverter turned off).
Choose Start frequency/voltage clockwise [3] to
obtain the function described in parameter 130
= factory setting. () = display text [] = value for use in communication via serial communication port
72
Start frequency and 131 Voltage at start during start
delay time. Regardless of the value assumed by
the reference signal, the output frequency equals
the setting in parameter 130 Start frequency and
the output voltage will correspond to the setting
in parameter 131 Voltage at start .
This functionality is typically used in hoist applications.
It is used in particular in applications in which a cone
anchor motor is applied, where the direction of rotation
0.0 sec.
is to start clockwise followed by the reference direction.
Select Start frequency/voltage in reference direction
[4] to obtain the function described in parameter
130 Start frequency and 131 Voltage at start
during the start delay time.
The direction of rotation of the motor will always
follow in the reference direction. If the reference signal
equals zero, the output frequency will equal 0 Hz,
while the output voltage will correspond to the setting
in parameter 131 Voltage at start. If the reference
signal is different from zero, the output frequency will
equal parameter 130 Start frequency and the output
voltage will equal parameter 131 Voltage at start. This
functionality is used typically for hoist applications with
counterweight. It is used in particular for applications
in which a cone anchor motor is applied. The cone
anchor motor can break away using parameter 130
[0]
Start frequency and parameter 131 Voltage at start.
[1]
122 Function at stop
[2]
(FUNCTION AT STOP)
[3]
Value:
Coasting (COAST)
[4]
DC hold (DC HOLD)
Function:
This is where to choose the function of the frequency
converter after the output frequency has become
lower than the value in parameter 123 The min.
frequency for acti v ation of function at stop or after
a stop command and when the output frequency
has been ramped down to 0 Hz.
Description of choice:
Select Coasting [0] if the frequency converter is to
'let go' of the motor (inverter turned off).
Select DC hold [1] if parameter 137 DC hold
voltage is to be acti v ated.
MG.28.E9.02 - VLT is a registered Danfoss trademark
®
VLT 2800 Series
[0]
[1]