SEL-487V Data Sheet Schweitzer Engineering Laboratories, Inc.
16
=>>SET T <Enter>
1: PMV01,THETA
(assign the alias “THETA” to math variable PMV01)
2: PMV02,TAN
(assign the alias “TAN” to math variable PMV02)
=>>SET L <Enter>
1: # CALCULATE THE TANGENT OF THETA
2: TAN:=SIN(THETA)/COS(THETA)
(use the aliases in an equation)
Add programmable control functions to your relay and
automation systems. New functions and capabilities
enable using analog values in conditional logic
statements. The following are examples of possible
applications of SEL
OGIC control equations with
expanded capabilities.
➤ Scale analog values for SCADA retrieval.
➤ Initiate remedial action sequence based on load
flow before fault conditions.
➤ Interlock breakers and disconnect switches.
➤ Restrict breaker tripping in excessive duty situa-
tions without additional relays.
➤ Construct a compensated overvoltage element for
open line overvoltage protection.
➤ Hold momentary change-of-state conditions for
SCADA polling.
➤ Provide a combination of frequency or rate-of-
change frequency functions.
Relay-to-Relay Digital
Communication (M
IRRORED BITS)
The SEL patented MIRRORED BITS technology provides
bidirectional relay-to-relay digital communication
(Figure 16). In the SEL-487V, M
IRRORED BITS can
operate simultaneously on any two serial ports for three-
terminal power system operation.
This bidirectional digital communication creates
additional outputs (transmitted M
IRRORED BITS) and
additional inputs (received M
IRRORED BITS) for each
serial port operating in the M
IRRORED BITS
communications mode. Communicated information can
include digital, analog, and virtual terminal data. Virtual
terminal allows the operator access to remote relays
through the local relay M
IRRORED BITS port. These
M
IRRORED BITS can be used to transfer information
between the SEL-487V and other system voltage
regulation devices to provide enhanced system voltage
and power factor control. The dual-port M
IRRORED BITS
communications are capable of high-speed
communications-assisted schemes for the protection and
control of capacitor bank applications.
Communication
The SEL-487V offers the following serial
communication features:
➤ Four independent EIA-232 serial ports.
➤ Full access to event history, relay status, and meter
information.
➤ Strong password protection for settings and group
switching.
➤ DNP3 Level 2 Server.
➤ Patented SEL Fast Message interleaving of ASCII
and binary data for SCADA communications,
including access to SER, relay element targets,
event data, and more.
➤ Communication of synchronized phasor measure-
ment data using either SEL Fast Messaging for
Synchrophasors or IEEE C37.118-2005 Standard
for Synchrophasors for Power Systems.
Ta b le 7 S E L OGIC Control Equation Operators
Operator Type Operators Comments
Boolean AND, OR, NOT Allows combination of measuring units.
Edge Detection F_TRIG, R_TRIG Operates at the change of state of an internal function.
Comparison >, >=, =, <=, <, < >
Arithmetic +, -, *, / Uses traditional math functions for analog quantities in an easily pro-
grammable equation.
Numerical ABS, SIN, COS, LN, EXP, SQRT
Precedence Control ( ) Allows multiple and nested sets of parentheses.
Comment # or (* *) Provides for easy documentation of control and protection logic.
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