Basic functions
7.20 Tolerant encoder monitoring
Drive functions
380 Function Manual, 11/2017, 6SL3097-4AB00-0BP5
Setting the measuring time to evaluate speed "0"
This function is only necessary for slow-speed drives (up to 40 rpm rated speed) in order to
be able to output actual speeds correctly close to 0. For a stationary drive, this prevents that
the I component of the speed controller slowly increases and the drive unnecessarily
establishes a torque.
1. Enter the required measuring time in parameter p0453: A speed actual value of 0 is
output, if, within this time, no pulses are detected from the A/B track.
Sliding averaging of the speed actual value
For slow-speed drives (< 40 rpm), when using standard encoders with a pulse number of
1024, a problem is encountered due to the fact that the same number of encoder pulses is
not available for every current controller cycle (for p0430.20 = 1: Speed calculation without
extrapolation, "Incremental difference"). The different number of encoder pulses means that
the speed actual value display jumps, although the encoder itself is rotating at a constant
speed.
1. For sliding averaging, set parameter p0430.20 = 0 (edge time measurement).
2. In parameter p4685, enter the number of current controller cycles over which the average
value should be formed to calculate the speed.
The averaging means that individual incorrect pulses, depending on the number of
specified cycles, are smoothed.
To Next Page
Loading...
Need help?
General