KEB COMBIVERT F5 Reference Manual page 157

LE04
Sample Rate for
Encoder 1
LE05
Encoder 1 Multiplier
i
This parameter is used to adjust the sample time of the encoder feedback for
calculation of the actual motor speed value. With certain motors or encoders
it may be beneficial to use a time other than the factory setting. Lower values
lead to higher bandwidth and faster response times of the motor. However
lower values also increase the systems susceptibility to electrical noise on
the encoder signal. Therefore on some systems having higher noise levels,
lower values may not be suitable. If this electrical noise is a problem, the
motor will produce an audible noise or vibration while running. If this is the
case, try increasing the rate by one step (e.g. from 4ms to 8ms) as a way to
filter electrical noise.
Settings:
0.5 msec(2 kHz)
1 msec (1 kHz)
2 msec (500 Hz)
4 msec (250 Hz)
8 msec (125 Hz)
16 msec (63 Hz)
32 msec (31 Hz)
Default = 4 msec (250 Hz) (3)
This parameter can be used to increase the resolution of encoders with analog
sine/cosine tracks. The encoder types are EnDat, SIN/COS, SSi, and Hiperface.
For incremental encoders, adjustment of this parameter has no effect; internally,
the value will be set to a value of 2 due to the TTL pulse tracks.
Default Setting (Gearless modes) = 8
Default Setting (Geared modes) = 2
The value corresponds to the multiplier using the following relation:
Actual Encoder Resolution =
Example:
EnDat encoder with base resolution of 2048 ppr.
With LE05 = 8 the actual measured resolution is:
2048 x 2^8 = 524288 counts / rev
Higher values give better resolution especially for gearless applications.
However values too high may make the system more susceptible to
disturbances due to noise. Therefore the actual value which can be used
will ultimately be limited by the noise being picked up on the encoder
cable. In gearless applications, very low values will sacrifice resolution
and may cause audible electrical noise from the motor. A setting of 8 is
typical for absolute encoders (e.g. EnDat).
LE - Encoder Parameters
NUM
0
1
2
3
4
5
6
Encoder base ppr (LE02) x 2^(LE05)
157