Setting The Measuring Time To Evaluate Speed "0; Sliding Averaging Of The Speed Actual Value - Siemens SINAMICS S120 Function Manual

7.19.10

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.
Commissioning
1. Enter the required measuring time in parameter p0453: A speed actual value of 0 is
7.19.11

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.
Commissioning
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
Drive functions
Function Manual, (FH1), 04/2014, 6SL3097-4AB00-0BP4
output, if, within this time, no pulses are detected from the A/B track.
value should be formed to calculate the speed.
The averaging means that individual incorrect pulses, depending on the number of
specified cycles, are smoothed.
Basic functions
7.19 Tolerant encoder monitoring
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