U-ONE
®
-SAFETY-LWL
Configuration manual
USL_KonfigManual-en_R3
7
1.2 System structure and function
The USL consists of a basic device, a section of fibre optic cable, a UO-SCU module, and other
optional modules.
The SCU is the central control module for the USL. All function modules and the basic device
are registered and managed in the UO-SCU. USB communication between the PC and USL, as
well as firmware updates of the individual modules, are controlled by the UO-SCU. The overall
system fulfils the requirements of certification level SIL CL2 / PL d.
Application:
Applications are in heavy-duty machinery, such as crane and harbour technology, mining, the
steel industry, oil and gas or offshore areas, as well as in general in drives with functional safety
requirements.
Figure 1-1 shows a basic unit with a section of fibre optic cable and the modules UO-SCU
(controller), UO-SGS-R (speed switch), UO-SRC-R (position switch), and UO-EPB-1 (Profibus
interface). Yellow modules are safety-related (safe), while those shown as grey are not (non-
safe). Modules are electrically connected via DIN rail bus connectors.
In addition to the UO-SCU module,
a maximum of 5 switching modules (corresponding to 15 switching outputs), may be
combined, a maximum of 2 of which may be UO-SGS-R speed switching modules,
plus a maximum of 2 bus modules. Different bus types and safe and non-safe types may be
combined.
Fig. 1-1: Basic unit with 4 modules
