Siemens SINAMICS S150 NEMA, Operating Instructions Manual

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Functions, monitoring and protective functions
9.3 Drive functions
Enclosed Drives
596
Operating Instructions, 12/2018, A5E36652151A
Principle of operation
● This function completely corrects encoder pulse errors up to the tolerance window
(p4681, p4682) between two zero marks. The rate of correction is 1/4 encoder pulses per
current controller cycle clock. As a consequence, it is possible to continually compensate
for missing encoder pulses (for example, if the encoder disk is dirty). The tolerance for the
deviating pulse number is set using the two parameters.
If the deviation exceeds the tolerance window size, fault F3x131
1)
is output.
Note
When the function "Commutation with zero mark" (p0404.15 = 1) is activated, then the
system waits until fine synchronization has been completed before making a correction
(r1992.8 = 1).
The rotor position for commutation is also corrected. Rotor position adaptation (p0430.22
= 1) does not have to be activated to do this.
This function does not make any corrections in the speed sensing.
● The minimum length of the zero mark is set using p4686. 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).
● Zero mark deviations of less than the minimum zero mark length (p4686) are not
corrected.
● A permanently failed zero mark is indicated using fault F3x101 "Zero mark failed"
1)
or
alarm A3x401 "Alarm threshold zero mark failed"
1)
.
1)
x = encoder number (x = 1, 2 or 3)
9.3.25.12 "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
"Monitoring tolerance band, pulse number" is activated with p0437.2 = 1.
The upper and the lower limit values of the tolerance band can be set using p4683 and
p4684. Within this tolerance band, the detected number of pulses is considered to be
correct.