User's Manual

Model CH45
EIA 422 or 485
2-5
The DYMEC-DynaStar Optical Stars can also be used to create a multi-drop Master / Slave
Optical Star network. The Model CH45 is optically compatible with the OS5 and OS9 Master
and Slave ports. Figure 11 shows a typical connection of an Optical Star network.
The master IED must always be connected to the Master port (port 1) of the Optical Star. The slave IED’s
must always be connected to the Slave ports (port 2 and up) of the Optical Star.
Variations of this configuration are as follows:
The optical star may be the last node of an optical bus configuration. One may create an Optical Bus
configuration starting with the Master IED to a series of Slave IEDs and then connect the fiber network to
the Master port of the OS5 or OS9 to continue the network in a “Hub and Spoke” topology.
A Master IED may be connected to the master port of an OS5 or OS9 and then an Optical Bus network may
be created from any Slave Port of the Optical Star.
The Optical Stars may be “cascaded”. Cascading means optically connecting a Slave Port of one Optical
Star to the Master Port of the next Optical Star.
IEDs of different electrical formats (i.e., RS-232, EIA 422, EIA 485 2-wire or EIA 485 4-wire) may also be
interconnected optically in the Star Configuration. Refer to section 3.5.
NOTE
It is not recommended that a “loop network” be connected to an Optical Star’s Slave Port