Gray/Binary Converter; Transmitted Encoder Value And Standardization - Siemens SIMATIC ET 200S Operating Instructions Manual

1SSI
4.6 Functions of the 1SSI
4.6.3

Gray/Binary Converter

Description
When Gray is set, the encoder value supplied by the absolute encoder in gray code is
converted to binary code. When Binary is set, the supplied encoder value is not converted.
Notice
If you selected the Gray setting, the 1SSI always converts the total encoder value (13, 16,
21, 24, and 25 bits). Preceding special bits thus influence the encoder value and trailing bits
can under some circumstances be corrupted.
4.6.4

Transmitted Encoder Value and Standardization

Description
The transmitted encoder value contains the encoder position of the absolute value encoder.
Depending on the encoder that is used, other bits that are located before and after the
encoder position are transmitted in addition to the encoder position.
So that the 1SSI can determine the encoder position, specify the following:
• Encoder type
• Number of trailing bits
• Total steps of the absolute encoder
With normalization, you specify the representation of the encoder value in the feedback
interface.
• With "Normalization On", you specify that trailing, irrelevant bits in the encoder value are
• With "Normalization Off", you specify that trailing bits are retained and are available for
232
to be discounted (see the following example).
evaluation.
Technological Functions
Operating Instructions, 02/2007, A5E00124867-05