User's Manual

Model CH45
EIA 422 or 485
1-1
1. INTRODUCTION
The DYMEC-DynaStar Model CH45 is a data communication Link/Repeater Card, for use in the
DYMEC-DynaStar 3900 Series Chassis, which allows the replacement of copper wire with fiber optic
cable. Link/Repeaters simply convert electrical signals to light for transmission, then, when received,
convert the light to electrical signals. This is done for EIA 422 and EIA 485 formats.
Link/Repeaters are passive to software protocol. They are not addressable by communication protocols
and do not provide any control logic capability supporting communication protocols. Link/Repeaters are
designed with several features that allow easy installation and flexibility in configuring for various
communication systems.
One should read all of this manual to fully understand how to use the many features of the
Link/Repeaters in an effective communication system.
1.1 DEFINITIONS
The following terms are used in this manual:
IED:
An IED is any intelligent electrical device capable of EIA 422 and/or EIA 485 data
communication, such as; a computer, RTU, PLC, "smart" meter, relay, etc. The IED must have
resident software or firmware that manages the data communication logic, including protocol
(formatting and timing), addressing capability (if required), control logic software "handshaking",
and scheduling.
Point-to-Point Configuration:
Two Link/Repeaters connected directly to each other.
Master/Slave Loop Configuration:
More than two Link/Repeaters connected together where the FOC connects the T optical port of
one device to the R optical port of the next unit in the loop. One IED is designated as the Master
and controls all the communication and the other IEDs act as Slaves and respond only when
specifically polled by the Master.
Peer-to-Peer Loop Configuration:
More than two Link/Repeaters connected together where the FOC connects the T optical port of
one device to the R optical port of the next unit in the loop. Each IED has the capability of
becoming loop Master as allowed by the controlling software. Not Supported by the CH45.
Echo:
The return of the Master's transmission back to the Master after traveling around the optical
loop.
Optical Bus Configuration:
More than two Link/Repeaters connected together in a “linear” topology and there is no
returning echo of a transmission.
Optical Star Configuration:
More than two Link/Repeaters connected together in a “Hub and Spoke” topology and there is
no returning echo of a transmission.
Master:
The Master is the IED which controls the network in a Master/Slave configuration. This IED is
responsible for the control of the network, the polling of the Slaves for information, and the
prevention of data collisions. In a loop configuration, the Master’s communication is echoed
back to and stops at the Master. The Master's mode Jumpers are always in the "OFF" position.