Notes On Commissioning Ssi Encoders - Siemens SINAMICS S120 Commissioning Manual

When the drive is synchronized, the difference between the EMF/phase U and the electrical
rotor position is a maximum of 10°.
If the difference is greater, the commutation angle offset must be adjusted.
2.14

Notes on commissioning SSI encoders

Using error bits
The number and position of error bits may vary for SSI encoders. In the event of faults, error
codes may even sometimes be transferred within the position information.
It is therefore essential that you assess all the error bits present (see "Parameterization" and
"Limitations" in this chapter) as otherwise an error code may be interpreted as position
information if faults are present.
Hardware requirements
● SMC20 Sensor Module Cabinet-Mounted
● SME25 Sensor Module External
● SMC30 Sensor Module Cabinet-Mounted
● CU320-2 Control Unit
Types of encoder that can be connected
Table 2- 19 Overview of encoder types that can be connected depending on the SIEMENS evaluation module
Encoder Incremental tracks
evaluation
through module
SMC20 sin/cos, 1 Vpp
SME25 sin/cos, 1 Vpp
SMC30 Square or
no incremental
tracks
"not cyclic" means that the absolute position is only read when initializing the Sensor Module, after which the position is
1)
only calculated by the incremental tracks.
"cyclic" means that the absolute position is read permanently (usually in the PROFIBUS or position controller cycle) and
2)
the position (X_IST1) formed from this.
the SSI protocol is cyclically read-out for the plausibility checks
3)
Commissioning Manual
Commissioning Manual, (IH1), 01/2012, 6SL3097-4AF00-0BP2
Absolute position
SSI not cyclic
1)
SSI not cyclic
1)
SSI not cyclic
1), 3)
SSI, cyclic
2)
2.14 Notes on commissioning SSI encoders
Power supply for SSI baud rate
encoder
5 V 100 kBaud
5 V 100 kBaud
5 V or 24 V 100-
250 kBaud
Commissioning
Remarks
-
SME25 is only
suited to direct
measuring
systems
-
167