Danfoss VLT AutomationDrive FC 302 Programming Manual page 78

Parameter Descriptions
3.6.2 4-3* Motor Feedback Monitoring
The parameter group includes monitoring and handling of
motor feedback devices as encoders, resolvers etc.
4-30 Motor Feedback Loss Function
3 3
Option:
[0] Disabled
[1] Warning
[2] Trip
*
[3] Jog
[4] Freeze Output
[5] Max Speed
[6] Switch to Open
Loop
[7] Select Setup 1
[8] Select Setup 2
[9] Select Setup 3
[10] Select Setup 4
[11] stop & trip
Warning 90 is active as soon as the value in
parameter 4-31 Motor Feedback Speed Error is exceeded,
regardless of the setting of parameter 4-32 Motor Feedback
Loss Timeout. Warning/Alarm 61 Feedback Error is related
to the Motor Feedback Loss Function.
4-31 Motor Feedback Speed Error
Range:
300 RPM [1 - 600 RPM] Select the max allowed error in speed
*
76
®
VLT AutomationDrive FC 301/302 Programming Guide
Function:
This function is used to monitor for
consistency in feedback signal, i.e. if the
feedback signal is available.
Select which reaction the frequency
converter should take if a feedback fault
is detected. The selected action is to take
place when the feedback signal differs
from the output speed by the value set in
parameter 4-31 Motor Feedback Speed Error
for longer than the value set
inparameter 4-32 Motor Feedback Loss
Timeout.
Function:
(output speed vs. feedback).
MG33MI02 - Rev. 2013-11-20
Speed
[rpm]
P 4-31
Illustration 3.31 Motor Feedback Speed Error
4-32 Motor Feedback Loss Timeout
Range: Function:
0.05 s [0 - 60 Set the timeout value allowing the speed
*
s] error set in parameter 4-31 Motor Feedback
Speed Error to be exceeded before enabling
the function selected in parameter 4-30 Motor
Feedback Loss Function.
4-34 Tracking Error Function
Option: Function:
This function is used to monitor that the
application follows the expected speed profile.
In Closed loop the speed reference to the PID is
compared to the encoder feedback (filtered) In
open loop the speed reference to the PID is
compensated for slip and compared to the
frequency that is sent to the motor
(16-13 Frequency).
The reaction is activated, if the measured
difference is more than specified in
parameter 4-35 Tracking Error for the time
specified in parameter 4-36 Tracking Error
Timeout.
A tracking error in closed loop does not imply
that there is a problem with the feedback
signal! A tracking error can be the result of
torque limit at too big loads.
[0] Disable
[1] Warning
[2] Trip
[3] Trip after
stop
Warning/Alarm 78 Tracking Error is related to the Tracking
Error Function.
n
calc
n
actual
P 4-32 Time
[sec]