Schweitzer Engineering SEL-2032, Instruction Manual

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1.7
Date Code 20120126 Instruction Manual SEL-2032 Communications Processor
Introduction and Specifications
Integration With the SEL-2032
SEL Protocol
In the system shown in Figure 1.5 , there is one cable between the SEL IEDs
and the SEL-2032. The communications protocol used on this link is the SEL
family of binary and ASCII messages sometimes called SEL Interleave. This
powerful protocol and the combination of IRIG-B on the 9-pin serial ports of
the IEDs and SEL-2032 allow you to use one cable and provide functions in
all of the basic integration areas.
Because the messaging is interleaved, an engineering connection through the
modem does not halt the collection of status and measurement data for
SCADA. The ASCII engineering connection shares the cable with the binary
data collection and control messages.
Using this SEL protocol, you can take advantage of a feature of the SEL-2032
called auto-configuration. When you connect an SEL IED to the SEL-2032,
you can initiate an auto-configuration process where the SEL-2032 learns
about the IED and what information and control points are available to the
SEL-2032.
Star Network
The SEL solution is a star network. This means that the system is inherently
more reliable. The star network is not subject to the same modes of failure as a
multidrop network that can cause all network operation to cease. Unlike
RTUs, industrial PCs, and other integration solutions, the SEL-2032 is built
and tested to the same standards as SEL protective relays.
In a star network architecture, the central node can be a possible single point
for failure. Because the SEL-2032 is many times more reliable than traditional
integration solutions, the SEL-2032 system is many times more reliable than
systems constructed of multiple single-purpose networks. You can also
increase reliability by adding a second SEL-2032 and making independent
connections to the IEDs. This increased reliability configuration is still
simpler to cable, install, and design than the solution shown in
Figure 1.4 .
The star network is also less expensive to build. First, there is only one cable
per device requiring less wiring and fewer chances for mistakes and future
failures. Second, you can use fiber-optic cables and SEL fiber-optic
transceivers to provide the ultimate in noise immunity and electrical isolation
without expensive and unreliable star couplers. The SEL solution is the only
integration system that allows you to distribute high-accuracy IRIG-B timing
signals via fiber-optic cables rather than coaxial cable.
If you are integrating non-SEL devices, the independent point-to-point
connections of the star network allow you to integrate devices with different
protocols and different communication speeds and media without having to
convert all devices to a common connection type and protocol.
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