Siemens SINAMICS S120, Function Manual

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Basic functions
7.24 Terminal Module 41
Drive functions
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
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Example of a pulse number step-up ratio with several zero positions
If the original encoder has several zero positions/marks per revolution (e.g. resolver with
several pole pairs), the correct zero mark must be selected via an additional condition.
Otherwise, there is no reproducible relationship between the position of the original encoder
and the zero mark position of the encoder emulation.
Figure 7-21 Step-up ratio with several zero positions per revolution
Parameterization
The pulse numbers of the leading encoder (the signal source) are set using p4408 and
p4418. To synchronize the generated zero mark with the zero mark of the leading encoder,
the pulse number per encoder revolution of the encoder at the TM41 input (p4408) must
always precisely coincide with the pulse number per encoder revolution of the encoder
interconnected at connector input p4420.
The pulse numbers emulated by the TM41 are set using p0408 and p0418. If p4408 = 0 is
set then the values from p0408 and p0418 also apply for the output of the TM41.
Diagnostic options
Parameter r4419 shows the calculated position setpoint after the step-up/step-down. Using
the trace function of the STARTER commissioning tool, you can check the step-up/step-
down function based on r4419.
Enabling the zero mark output of the TM41
For p4401.1 = 1, the zero mark from the leading encoder is also output from the TM41. For
p4401.1 = 0, TM41 outputs the zero pulse at the position at which the TM41 was located
when switching on.