Start Delay; Flying Start; Function At Stop; Motor Thermal Protection - Danfoss vlt FC 102 Operating Instructions Manual

®
VLT HVAC Drive Operating Instructions

1-71 Start Delay

Range:
*
0.0s [0.0 - 120.0 s]
This function makes it possible to catch a motor which is spinning freely due to a mains drop-out.

1-73 Flying Start

Option:
*
Disabled
[0]
[1] Enabled
Search direction for flying start is linked to the setting in
Clockwise
[0]: Flying start search in clockwise direction. If not successful, a DC brake is carried out.
Both Directions
[2]: The flying start will first make a search in the direction determined by the last reference (direction). If not finding the speed it will
make a search in the other direction. If not successful, a DC brake will be activated in the time set in
from 0 Hz.

1-80 Function at Stop

Option:
*
Coast
[0]
* DC hold/Preheat
[1]

1-90 Motor Thermal Protection

Option:
[0] No protection
[1] Thermistor warning
[2] Thermistor trip
Function:
Function at Stop
The function selected in par. 1-80
Enter the time delay required before commencing acceleration.
Function:
Disable
Select [0] if this function is not required.
Select Enable [1] to enable the frequency converter to "catch" and control a spinning motor.
When par. 1-73 is enabled, par. 1-71 Start Delay
par. 4-10, Motor Speed Direction.
Function:
Select the frequency converter function after a stop command or after the speed is ramped down to the settings
Min Speed for Function at Stop [RPM]
in par. 1-81
Leaves motor in free mode.
Energizes motor with a DC holding current (see par. 2-00).
Function:
The frequency converter determines the motor temperature for motor protection in two different ways:
• Via a thermistor sensor connected to one of the analog or digital inputs (par. 1-93
Source ).
• Via calculation (ETR = Electronic Thermal Relay) of the thermal load, based on the actual load and
time. The calculated thermal load is compared with the rated motor current I
frequency f . The calculations estimate the need for a lower load at lower speed due to less cool-
M,N
ing from the fan incorporated in the motor.
If the motor is continuously overloaded and no warning or trip of frequency converter is wanted.
Activates a warning when the connected thermistor in the motor reacts in the event of motor over-temperature.
Stops (trips) the frequency converter when the connected thermistor in the motor reacts in the event of motor
over-temperature.
MG.11.A6.02 - VLT ® is a registered Danfoss trademark
6. How to programme the frequency converter
is active in the delay period.
has no function.
par. 2-02, Braking Time
.
. Start will then take place
Thermistor
and the rated motor
M,N
79
6