Danfoss VLT Programming Manual page 105

Parameter Description
Illustration 3.2 Controlled Ramp down - short mains failure. Ramping down to stop followed by ramping up to reference.
3 3
Illustration 3.3 Controlled Ramp down, longer mains failure. Ramping down as long as the energy in the system allows for it, then the motor is
coasted.
Illustration 3.4 Kinetic Back-up, short mains failure. Ride through as long as the energy in the system allows for it.
Illustration 3.5 Kinetic Back-up, longer mains failure. The motor is coasted as soon as the energy in the system is too low.
14-11 Mains Voltage at Mains Fault
Range:
Size related
*
V]
14-12 Function at Mains Imbalance
Option:
[0] Trip
*
[1] Warning Select Warning [1] to issue a warning.
[2] Disabled Select Disabled [2] for no action.
104
Function:
[180 - 600 This parameter defines the threshold
voltage at which the selected function
in 14-10 Mains Failure should be
activated. The detection level is at a
faktor sqrt(2) of the value in 14-11.
Function:
Operation under severe main imbalance conditions
reduces the lifetime of the motor. Conditions are
considered severe if the motor is operated contin-
uously near nominal load (e.g. a pump or fan
running near full speed).
When a severe mains imbalance is detected:
Select Trip [0] to trip the frequency converter.
MG.11.CB.02 - VLT
®
VLT HVAC Drive Programming Guide
DC Voltage
Output Speed rpm
Over Voltage Control Level
Par 14-11
Time
Mains
DC Voltage
Output Speed rpm
Over Voltage Control Level
Par 14-11
Mains
DC Voltage
Output Speed rpm
Over Voltage Control Level
Par 14-11
Mains
DC Voltage
Output Speed rpm
Over Voltage Control Level
Par 14-11
Time
Mains
14-12 Function at Mains Imbalance
Option:
[3] Derate
®
is a registered Danfoss trademark
Time
Time
Function:
Select Derate [3] for derating the frequency
converter.