Danfoss VLT AutomationDrive FC 301 Programming Manual page 86

Parameter Descriptions
4-24 Brake Check Limit Factor
Range:
98 [0 -
% 100 %
*
]
3 3
3.6.2 4-3* Motor Feedback Monitoring
The parameter group includes monitoring and handling of
motor feedback devices, such as encoders, resolvers, and
so on.
4-30 Motor Feedback Loss Function
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
84
Function:
Enter the limit factor that parameter 2-15 Brake
Check uses when performing the brake check. The
frequency converter uses the limit factor
depending on the selection in
parameter 4-23 Brake Check Limit Factor Source:
[0] DC-link voltage - the frequency converter
applies the factor to the EEPROM data in the DC-
link.
[1] Analog Input 53 or [2] Analog Input 54 - the
brake check fails if the input current on the analog
input is lower than the maximum input current
multiplied by the limit factor.
For example, in the following configuration the
brake check fails if the input current is lower than
16 mA:
•
A current transducer with a range of 4-20
mA is connected to analog input 53.
•
Parameter 4-24 Brake Check Limit Factor is
set to 80%.
Function:
This function is used to monitor
consistency in feedback signal, that is 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 in
parameter 4-32 Motor Feedback Loss
Timeout.
Danfoss A/S © 02/2016 All rights reserved.
®
VLT AutomationDrive FC 301/302
Warning 90 Feedback monitor 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
Speed
[rpm]
Illustration 3.31 Motor Feedback Speed Error
4-32 Motor Feedback Loss Timeout
Range:
0.05 s
*
4-34 Tracking Error Function
Option:
Function:
[1 - 600 RPM] Select the maximum allowed error in
*
speed (output speed vs. feedback).
n
calc
n
actual
P 4-31
P 4-32
Function:
[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.
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
(parameter 16-13 Frequency).
The reaction is activated if the measured
difference is more than the value 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 heavy loads.
Time
[sec]
MG33ML02