Rockwell Automation 20B PowerFlex 70, PowerFlex 700 Reference Manual - Manual (Page 166)

Speed Feedback Filter
166 Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013
[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
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
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.
Speed Feedback Filter
[Fdbk Filter Select] determines the type of filter to use for the speed
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:
Vector
Vector
Description To select this type of filter . . . Select this value . . .
No filter 0
A light 35/49 radian
feedback filter 1
A heavy 20/40 radian
feedback filter 2
Vector
Gain
0 db
Rad/Sec
Gain
0 db
-6 db
Rad/Sec 49 35
Gain
0 db
-12 db
Rad/Sec 40 20