Siemens Sinamics s120 Commissioning Manual page 276

Commissioning
3.19 Commissioning of SSI encoders
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
waiting period of 800 ms.
● After the waiting period has expired, test signals are applied to the clock cable and the
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.
● If the encoder has not signaled that it is in the ready state after approx. 10 seconds, the
encoder evaluation module signals a timeout error.
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
accordance with the parameterized voltage level.
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.
Parameterization
● Predefined encoders
Various predefined SSI encoders are available for commissioning. These can be selected
in the commissioning windows of the STARTER commissioning tool.
● User-defined encoders
If there are no predefined entries for the encoder used, user-defined encoder data can be
entered via windows using the commissioning wizard.
276
STARTER Commissioning Manual
Commissioning Manual, (IH1), 07/2016, 6SL3097-4AF00-0BP5