GE Multilin G650, Manual

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GEK-113285A G650 Generator Protection & Control System 1-7
1 GETTING STARTED 1.2 OVERVIEW
1
1.2OVERVIEW 1.2.1 INTRODUCTION TO 650 FAMILY OF RELAYS
Historically, substation protection, control and metering functions were performed with electromechanical equipment. This
first generation of equipment was gradually replaced by analog electronic equipment (called static devices), most of which
emulated the single-function approach of their electromechanical precursors. Both of these technologies required
expensive cabling and auxiliary equipment to produce functioning systems.
Recently, digital electronic equipment has begun to provide protection, control and metering functions. Initially, this
equipment was either single function or had very limited multi-function capability, and did not significantly reduce the
cabling and auxiliary equipment required. However, recent digital relays have become quite multi-functional, reducing
cabling and auxiliaries significantly. These devices also transfer data to central control facilities and Human Machine
Interfaces using electronic communications. The functions performed by these products have become so broad that many
users prefer the term IED (Intelligent Electronic Device).
It is obvious to station designers that the amount of cabling and auxiliary equipment installed in stations can be even further
reduced, to 20% to 70% of the levels common in 1990, to achieve large cost reductions. This requires placing even more
functions within the IEDs.
Users of power equipment are also interested in reducing cost by improving power quality and personnel productivity, and
as always, in increasing system reliability and efficiency. These objectives are realized through software which is used to
perform functions at both the station and supervisory levels. The use of these systems is growing rapidly.
High speed communications are required to meet the data transfer rates required by modern automatic control and
monitoring systems. In the near future, very high speed communications will be required to perform protection signalling.
IEDs with capabilities outlined above will also provided significantly more power system data than is presently available,
enhance operations and maintenance, and permit the use of adaptive system configuration for protection and control
systems. This new generation of equipment must also be easily incorporated into automation systems, at both the station
and enterprise levels.
1.2.2 HARDWARE ARCHITECTURE
650 family of relays has been designed to meet the goals described above that are appearing nowadays in the environment
of new substations.
The 650 is a digital-based device containing a central processing unit (CPU) that handles multiple types of input and output
signals. The 650 family can communicate over a local area network (LAN) with an operator interface, a programming
device, or another 650 or UR device.
The
CPU module
contains firmware that provides protection elements in the form of logic algorithms, as well as
programming logic gates, timers, and latches for control features. It incorporates two internal processors, one for generic
use and a second one dedicated for communications.
Input Elements
accept a variety of analog or digital signals from the field. The 650 isolates and converts these signals into
logic signals used by the relay.
Output Elements
convert and isolate the logic signals generated by the relay into digital signals that can be used to control
field devices.