Siemens SIMATIC NET OLM12M Description And Operating Manual page 62

6ZB5530–3AB00–0BA0/01
5 Modes
Each optical channel can be switched separately to one of four different modes.
With one exception, any combination of the modes on the two channels is possible.
The exception is the combination of ring (passive) on both channels of a SIMATIC NET optical link
module since this combination implicitly means a multimaster connection to the optical single-fiber
rings.
You can set the following modes:
Line
Use this mode to set up optical bus topologies.
The line monitoring of the optical channel is active (only when OLM12M modules are used
exclusively).
A break on the fiber-optic cable on the receive channel is indicated by the LED system and the
signaling contact (only if you set Monitor = on).
Ring (active)
Use this mode to set up optical ring topologies.
In this mode, the optical channel is the coordinator (head station) of an optical single-fiber ring and
allows the connection of active and passive nodes to the optical single-fiber ring.
Note that only one optical channel can be set to this mode per optical single-fiber ring.
The line monitoring of the optical channel is activated.
A break on the FO cable in the single-fiber ring is signaled by the system LED and signaling
contact.
Ring (passive)
Use this mode to set up optical ring topologies.
In this mode, the SIMATIC NET optical link module allows the connection of passive nodes to the
optical single-fiber ring.
The line monitoring of the optical channel is deactivated.
Inactive
In this mode, the optical channel is deactivated. Sending and receiving of the deactivated channel is
disabled, line monitoring is deactivated.
All non-connected optical channels must be switched to this mode so that the line monitoring does
not signal an FO cable break.
Monitor
With the Monitor setting, the line monitoring of the optical channel can be deactivated regardless of
the mode setting (Monitor=off).
It is necessary to deactivate line monitoring when using OLM12M modules and OLM/P3 or OLM/P4
modules within an optical bus structure.
Copyright Siemens AG 1997
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SIMATIC NET OLM12M