Siemens SINAMICS S120 Commissioning Manual page 211

Note
Only encoders that support a transfer rate of 100 kHz and that have a high level in idle state
may be used.
The monoflop time should be parameterized such that it is greater than or equal to the
specified monoflop time of the encoder. This must lie in the range between 15 – 30 µs.
The level during the monoflop time must be low.
Ramp-up time of the encoder
In order to ensure that the correct sensor data is received, the encoder evaluation module
checks whether the connected encoder is activated and ready for operation:
● After the power supply is switched on at the encoder, no signals are evaluated for a
● After the waiting period has expired, test signals are applied to the clock cable and the
● If the encoder has not signaled that it is in the ready state after approx. 10 seconds, the
The waiting period starts again when:
● The 5 V power supply is applied to the encoder.
● Switchover to 24 V power supply after completed ramp-up of the encoder evaluation in
Note
The activation routine is started each time that the encoder is inserted. The activation routine
has been completed with the ready message to the evaluation module.
Note
An external 24 V encoder supply is permitted.
Commissioning Manual
Commissioning Manual, (IH1), 01/2013, 6SL3097-4AF00-0BP3
waiting period of 800 ms.
response of the data line observed. As long as the encoder is not ready, the encoder
holds the data line permanently in the idle state (as a rule, "high").
It is expected that the encoder has reached its ready state by this time.
encoder evaluation module signals a timeout error.
accordance with the parameterized voltage level.
2.14 Notes on commissioning SSI encoders
Commissioning
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