Tolerance Band Pulse Number" Monitoring - Siemens SINAMICS S120 Function Manual

Basic functions
7.19 Tolerant encoder monitoring
Sequence
1. This function completely corrects encoder pulse errors up to the tolerance window
(p4681, p4682) between two zero marks. The rate of correction is ¼ encoder pulses per
current controller cycle. As a consequence, it is possible to continually compensate for
missing encoder pulses (for example, if the encoder disk is dirty). Using the two
parameters, set the tolerance for the deviating pulse number.
If the deviation exceeds the tolerance window size, fault F3x131
Note
When the "Commutation with zero mark" function (p0404.15 = 1) is activated, then the
system waits until fine synchronization has been completed before making a correction
(r1992.8 = 1).
The pole position for the commutation is also corrected. To do this, you do not have to
activate pole position adaptation (p0430.22 = 1).
This function does not make any corrections in the speed sensing.
2. Using p4686, set the minimum zero mark length. With a factory setting of 1, it is
prevented that EMC faults result in a zero mark error.
Shorter zero marks are only suppressed when "Zero mark edge detection" is
parameterized (p0437.1 = 1).
3. Zero mark deviations of less than the minimum zero mark length (p4686) are not
corrected.
4. A permanently failed zero mark is indicated using the fault F3x101 "Encoder x: Zero mark
failed"
1)
7.19.8

"Tolerance band pulse number" monitoring

This function monitors the number of encoder pulses between two zero marks. An alarm is
output if the number lies outside a tolerance band that can be selected.
Commissioning
1. Set parameter p0437.2 = 1 to activate the monitoring.
2. Using parameters p4683 and p4684, set the upper and the lower limits of the tolerance
band. Within this tolerance band, the detected number of pulses is considered to be
correct.
340
or the alarm A3x401
1)
x = encoder number (x = 1, 2 or 3)
"Alarm threshold zero mark failed".
1)
Function Manual, (FH1), 04/2014, 6SL3097-4AB00-0BP4
is output.
1)
Drive functions