Signalling Of Line-Breaks In A Redundant Fibre-Optical Ring - Siemens SIPROTEC 7SA522 Manual

2.3.2

Signalling of line-breaks in a redundant fibre-optical ring

OLM status
indications
Allocation in DIGSI
Routing example
SIPROTEC PROFIBUS-DP - Communication profile
C53000-L1840-B001-03
If the SIPROTEC device is connected to the PROFIBUS network via a redundant opti-
cal ring topology then a (single) fibre-optical line-break does not lead to a communica-
tion interruption between the PROFIBUS-DP master and the PROFIBUS-DP slave.
This line-break however must be recognized and repaired because with this line-break
the redundancy is not present any more.
Configured for redundant optical ring topology the OLM-IC on the fibre-optical PRO-
FIBUS modules constantly checks for line-breaks to the two connected neighbor
devices.
Two OLM status indications ("Line-break Channel A" and "Line-break Chan-
nel B") are available which can be routed using DIGSI to SIPROTEC objects (Internal
single-point indications/Taggings) and then evaluated via CFC or LED indications in
the SIPROTEC device or transmitted to the PROFIBUS-DP master.
The two OLM status indications of the fibre-optical SIPROTEC communication module
are offered additionally to the routing possibilities of the selected mapping if an (previ-
ously created user-defined) Internal single-point indication/Tagging is routed to
"Source system interface" using the DIGSI Configuration matrix (ref. to
chap. 4.2):
• "Line-break Channel A"
Byte offset = FFFF
hex
• "Line-break Channel B"
Byte offset = FFFF
hex
Requirement:
The OLM status indications shall be transferred to the supervisory control system and
a break in the fibre-optical line is to be indicated with a LED at the SIPROTEC device.
Solution:
1. Insert two user-defined taggings (Internal single-point indications) in the DIGSI
Configuration matrix (ref. to Figure 2-1).
2. Name the inserted taggings, e.g. "OLMErr_A" und "OLMErr_B".
3. Routing of the inserted taggins in the column "Source system interface":
"OLMErr_A" at byte offset = 65535, Bit mask = 1
"OLMErr_B" at byte offset = 65535, Bit mask = 2
4. Routing of the taggings at free positions in the PROFIBUS-DP telegramm to the
PROFIBUS-DP master in the column "Destination system interface" and to "Des-
tination LED".
(65535), Bit mask = 1
(65535), Bit mask = 2
Parameters and properties
35