0.0 (OFF) - 0.5 sec.
OFF
Function:
In order to secure a high starting torque, the maximum
torque for max. 0.5 sec. is allowed. However, the cur-
rent is limited by the protection limit of the frequency
converter (inverter). 0 sec. corresponds to no high
break-away torque.
Description of choice:
Set the necessary time in which a high starting torque
is desired.
111
Start delay
(START DELAY)
Value:
0.0 - 120.0 sec.
0.0 sec.
Function:
This parameter enables a delay of the starting time af-
ter 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 desired time until acceleration is to begin.
112
Motor preheater
(MOTOR PREHEAT)
Value:
Disable (DISABLE)
[0]
Enable (ENABLE)
[1]
Function:
The motor preheater ensures that no condensate de-
velops in the motor at stop. This function can also be
used to evaporate condensed water in the motor. The
motor preheater is only active during stop.
Description of choice:
Select
Disable
[0] if this function is not required. Select
Enable
[1] to activate motor preheating. The DC current
is set in parameter 113
Motor preheater DC current
.
113
Motor preheater DC current
(PREHEAT DC-CURR.)
Value:
0 - 100 %
50 %
The maximum value depends on the rated motor
current, parameter 105
Motor current, I
M,N
.
Function:
The motor can be preheated at stop by means of a DC
current to prevent moisture from entering the motor.
Description of choice:
The motor can be preheated by means of a DC current.
At 0%, the function is inactive; at a value higher than
0%, a DC current will be supplied to the motor at stop
(0 Hz). This function can also be used to generate a
holding torque.
If too high a DC current is supplied for too
long, the motor can be damaged.
DC braking
In DC braking, the motor receives a DC current that
brings the shaft to a halt. Parameter 114
DC braking
current
, decides the DC braking current as a percent-
age of the rated motor current I
M,N
.
In parameter 115
DC braking time
, the DC braking time
is selected, and in parameter 116
DC brake cut-in fre-
quency
, the frequency is selected at which DC braking
becomes active.
If terminal 19 or 27 (parameter 303/304
Digital input
)
has been programmed to
DC braking inverse
and shifts
from logic “1” to logic “0”, the DC braking will be acti-
vated.
When the start signal on terminal 18 changes from
logic “1” to logic “0”, the DC braking will be activated
when the output frequency becomes lower than the
brake coupling frequency.
NB!
The DC brake is not to be used if the in-
ertia of the motor shaft is more than 20
times the inertia of the motor itself.
114
DC braking current
(DC BRAKE CURRENT)
Value:
0 =
I
VLT, MAX
I
M, N
× 100 %
50 %
The maximum value depends on the rated motor
current. If the DC braking current is active, the fre-
quency converter has a switching frequency of 4
kHz.
VLT
®
6000 HVAC Series
= factory setting, () = display text, [] = value for use in communication via serial communication port
112
MG.61.B5.02 - VLT
®
is a registered Danfoss trademark
Содержание VLT 6000 HVAC Series
Страница 31: ...Ordering form VLT 6000 HVAC Series MG 61 B5 02 VLT is a registered Danfoss trademark 31 Introduction to HVAC ...
Страница 63: ...Mechanical dimensions VLT 6000 HVAC Series MG 61 B5 02 VLT is a registered Danfoss trademark 63 Installation ...
Страница 75: ...VLT 6000 HVAC Series MG 61 B5 02 VLT is a registered Danfoss trademark 75 Installation ...
Страница 204: ...VLT 6000 HVAC Series 204 MG 61 B5 02 VLT is a registered Danfoss trademark ...