Danfoss VLT HVAC Operating Instructions Manual page 70

6. How to programme the frequency converter
Digital input 18
Digital input 19
Digital input 32
Digital input 33
Function:
Select the input to which the thermistor (PTC
sensor) should be connected. An analog input
option [1] or [2] cannot be selected if the an-
alog input is already in use as a reference
source (selected in par. 3-15
Source
Reference Source 3).
This parameter cannot be adjusted while the
motor is running.
6
2-00
Value:
0 - 100%
Function:
Enter a value for holding current as a percent-
age of the rated motor current I
1-24 Motor Current. 100% DC holding current
corresponds to I
This parameter holds the motor function
(holding torque) or pre-heats the motor.
This parameter is active if
in par. 1-80
2-10
Value:
Off
Resistor brake
Function:
Select
Select
incorporated in the system, for dissipation of
surplus brake energy as heat. Connecting a
brake resistor allows a higher DC link voltage
70
Reference Source
1, 3-16
DC Hold Current/Preheat
Current
M,N
.
M,N
DC hold
is selected
Function at Stop
.
NB!
The maximum value depends on
the rated motor current.
NB!
Avoid 100 % current for too
long. It may damage the motor.
Brake Function
Off
[0] if no brake resistor is installed.
Resistor brake [1] if a brake resistor is
MG.11.A4.02 - 09.10.06. VLT
VLT
during braking (generating operation). The
[3]
Resistor brake function is only active in fre-
[4]
quency converters with an integral dynamic
[5]
brake.
[6]
2-17 Over-voltage Control
Value:
Disabled
Reference
2 or 3-17
Enabled
Function:
Over-voltage control (OVC) reduces the risk of
the frequency converter tripping due to an
over voltage on the DC link caused by gener-
ative power from the load.
Disabled
Select
Enabled
Select
50 %
set in par.
[0]
[1]
® is a registered Danfoss trademark
®
HVAC Drive Operating Instructions
[0] if no OVC is required.
[2] to activate OVC.
NB!
The ramp time is automatically
adjusted to avoid tripping of the
frequency converter.
[0]
[2]