Two-Encoder System With Connection Via Sinamics S120; Two-Encoder System With Connection Via Distributed I/O - Siemens Simatic Manual

Storage and retrieval machines and safety functions
Figure 2: Single-encoder system
1.2.2

Two-encoder system with connection via SINAMICS S120

Sensing:

The sin/cos motor encoder is connected with the SINAMICS S120 via an SMC20 or a DRIVE CLiQ
interface (SMI), the direct measuring system (SSI) via an SMC30. The position control of the EPOS
is realized via the direct measuring system.
The position actual value of EPOS (basic positioner, drive function) must be transferred via the standard
telegram to obtain the two-channel structure for data transfer to the F-CPU. The position actual value of the
motor encoder is determined by SI and is transferred to the F-CPU using a safety-related telegram. The
motor encoder must be a safety-related encoder, suitable for safety applications. Safety-related mounting is
not required, as possible errors are monitored using the cross comparison with the second encoder.
Figure 3: Two-encoder system, version 1
1.2.3

Two-encoder system with connection via distributed I/O

Sensing:
a) Sin/cos motor encoder via PROFIsafe telegram from SINAMICS S120, direct measuring
system using a standard telegram of the SSI module (e.g. SM338) to the F-CPU.
Figure 4: Two-encoder system, version 2
b) Sin/cos motor encoder via PROFIsafe telegram from SINAMICS S120, direct encoder using a
standard telegram PROFIBUS/PROFINET-capable encoder.
S7-Distributed Safety/SIMATIC Safety - fail-safe function blocks for storage and retrieval machines
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