Speed Feedback Filter - Allen-Bradley PowerFlex 70 Reference Manual

Speed Feedback Filter

Speed Feedback Filter
166
[Motor Fdbk Type] selects the type of encoder:
• "Quadrature" – dual channel.
• "Quad Check" – dual channel and detects loss of encoder signal when using
differential inputs.
• "Single Chan" – pulse type, single channel.
• "Single Check" – pulse type, single channel and detects loss of encoder signal
when using differential inputs.
[Encoder PPR] sets the number of encoder pulses per revolution.
[Enc Position Fdbk] displays the raw encoder count. For single channel encoders,
this count will increase (per rev.) by the amount in [Encoder PPR]. For
quadrature encoders this count will increase by 4 times the amount defined in
[Encoder PPR].
Encoderless/Deadband
Vector
Encoderless/Deadband is recommended when more than a 120:1 speed range of
operation is not required and the user will set the speed reference below 0.5Hz/
15 RPM. The deadband will help prevent cogging and unstable motor operation
below a reference of 0.5Hz/15RPM by clamping the speed and torque regulators
to zero.
Simulator
Vector
The simulator mode allows the drive to be operated without a motor connected
and is meant for demo purposes only. If a motor is connected with this mode
selected very erratic and unpredictable operation will occur.
[Fdbk Filter Select] determines the type of filter to use for the speed
Vector
feedback. The filter is used to filter out high frequency signals (noise) by
reducing the gain at high frequencies. The selections for the filter are:
Description To select this type of filter . . .
No filter
Gain
0 db
A light 35/49 radian
Gain
feedback filter
0 db
-6 db
A heavy 20/40 radian
Gain
feedback filter
0 db
-12 db
Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013
Rad/Sec
35 49 Rad/Sec
20 40 Rad/Sec
Select this value . . .
0
1
2