5-136
G60 Generator Protection System
GE Multilin
5.5 FLEXLOGIC
5 SETTINGS
5
5.5FLEXLOGIC
5.5.1 INTRODUCTION TO FLEXLOGIC
To provide maximum flexibility to the user, the arrangement of internal digital logic combines fixed and user-programmed
parameters. Logic upon which individual features are designed is fixed, and all other logic, from digital input signals through
elements or combinations of elements to digital outputs, is variable. The user has complete control of all variable logic
through FlexLogic. In general, the system receives analog and digital inputs which it uses to produce analog and digital out-
puts. The major sub-systems of a generic UR-series relay involved in this process are shown below.
Figure 5–53: UR ARCHITECTURE OVERVIEW
The states of all digital signals used in the G60 are represented by flags (or FlexLogic operands, which are described later
in this section). A digital “1” is represented by a 'set' flag. Any external contact change-of-state can be used to block an ele-
ment from operating, as an input to a control feature in a FlexLogic equation, or to operate a contact output. The state of the
contact input can be displayed locally or viewed remotely via the communications facilities provided. If a simple scheme
where a contact input is used to block an element is desired, this selection is made when programming the element. This
capability also applies to the other features that set flags: elements, virtual inputs, remote inputs, schemes, and human
operators.
If more complex logic than presented above is required, it is implemented via FlexLogic. For example, if it is desired to have
the closed state of contact input H7a and the operated state of the phase undervoltage element block the operation of the
phase time overcurrent element, the two control input states are programmed in a FlexLogic equation. This equation ANDs
the two control inputs to produce a virtual output which is then selected when programming the phase time overcurrent to
be used as a blocking input. Virtual outputs can only be created by FlexLogic equations.
Traditionally, protective relay logic has been relatively limited. Any unusual applications involving interlocks, blocking, or
supervisory functions had to be hard-wired using contact inputs and outputs. FlexLogic minimizes the requirement for aux-
iliary components and wiring while making more complex schemes possible.
EnerVista UR Setup and LAN communications
DCmA
or
RTD
inputs
VTs
CTs
DSP
(A/D)
827022A7.cdr
Analog
input
(A/D)
Calculate
parameters
Contact
inputs
Keypad
Virtual
inputs
Remote
inputs
(GOOSE)
OR
fiber
G.703
RS422
Direct
inputs
Control
and
monitoring
features
Block
operation
(each
element)
Measuring
and
decision
elements
FlexLogic™
equations
Flags
FlexLogic™
counters
Virtual
outputs
Digital
elements
V
I
Form-A and
SCR only
Contact
outputs
Display
and LEDs
Remote
outputs
Display
Analog
output (D/A)
(dcmA)
Direct
outputs
Fiber
G.703
RS422
(Status)
(Status)
(Actual values)
(FlexLogic operands)
Summary of Contents for Multilin g60
Page 10: ...x G60 Generator Protection System GE Multilin TABLE OF CONTENTS INDEX ...
Page 32: ...1 22 G60 Generator Protection System GE Multilin 1 5 USING THE RELAY 1 GETTING STARTED 1 ...
Page 160: ...4 30 G60 Generator Protection System GE Multilin 4 3 FACEPLATE INTERFACE 4 HUMAN INTERFACES 4 ...
Page 486: ...5 326 G60 Generator Protection System GE Multilin 5 10 TESTING 5 SETTINGS 5 ...
Page 518: ...6 32 G60 Generator Protection System GE Multilin 6 5 PRODUCT INFORMATION 6 ACTUAL VALUES 6 ...
Page 532: ...7 14 G60 Generator Protection System GE Multilin 7 2 TARGETS 7 COMMANDS AND TARGETS 7 ...
Page 748: ...D 10 G60 Generator Protection System GE Multilin D 1 IEC 60870 5 104 APPENDIX D D ...
Page 760: ...E 12 G60 Generator Protection System GE Multilin E 2 DNP POINT LISTS APPENDIX E E ...