SIGMATEK SNC 021, Руководство пользователя

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SNC 021 S-DIAS SAFETY SNC INCREMENTAL ENCODER
Page 28 02.12.2019
11 Installing the Encoder
Line and encoder errors are diagnosed using, among other things, the measurement of the
encoder currents.
For this purpose, the preset values for measuring current must be defined in the system. The
current limits are defined in the automatic system automatically, so the user does not have to
predefine or configure any additional parameters.
In the unverified status of the system, the encoder currents are measured while starting the
system and used as temporary reference values. Based on the determined reference values,
the current limits are temporarily defined with ±25%. If a corresponding fluctuation in the
encoder currents due to a wiring fault is detected during movement, the system switches to
the Safe mode and the appropriate diagnostic codes are provided.
CAUTION!
Before the Safety system is labeled as verified, the wiring of the installed encoder must be
checked manually to ensure that the system operates error-free (the encoder operates
without fault).
During verification, which is
run via the “Set Verified” button in the SafetyDesigner or the
validation button on the Safe CPU, the actual current measurements are used to determine
the permissible limit values for the encoder current and then stored in the Safe CPUs remnant
data. These limit values are based on the measured value ±25 %.
After successful validation, the encoder currents are monitored using the current values
stored in the Safe CPU. When in verified status, the upper or lower limits are exceeded, the
system changes to safe mode and the appropriate diagnostic code for error analysis is again
provided.
In the standard application, the actual and preset current values are provided via the
hardware classes.
CAUTION! Exchanging the encoder
Basically, the Safety system cannot detect an encoder exchange when no power is applied.
The parameters of the new encoder could be different from the replaced encoders with regard
to the currents, whereby it is no longer possible guarantee the appropriate monitoring of the
newly installed encoder.
In such a case, the system
must be reverified. This means reconfiguring the Safe CPU via
the SafetyDesigner or µSD card and verifying (see Safety System manual)