Grouped Elements; Overview - GE B90 Instruction Manual

CHAPTER 5: SETTINGS
The non-volatile latches provide a permanent logical flag that is stored safely and do not reset upon restart after the relay
is powered down. Typical applications include sustaining operator commands or permanently blocking relay functions,
such as Autorecloser, until a deliberate interface action resets the latch.
— This setting characterizes Latch 1 to be Set- or Reset-dominant.
LATCH 1 TYPE
— If asserted, the specified FlexLogic operands 'sets' Latch 1.
LATCH 1 SET
— If asserted, the specified FlexLogic operand 'resets' Latch 1.
LATCH 1 RESET
Figure 5-73: Non-volatile latch operation table (N = 1 to 16) and logic

5.6 Grouped elements

5.6.1 Overview

Each protection element can be assigned up to six sets of settings with designations 1 to 6. The performance of these
elements is defined by the active setting group at a given time. Multiple setting groups allow the user to conveniently
change protection settings for different operating situations (for example, altered power system configuration or season of
the year). The active setting group can be preset or selected in the
later in this chapter). See also the Introduction to Elements section at the beginning of this chapter.
B90 LOW IMPEDANCE BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
LATCH 1 RESET:

Off
LATCH 1

TARGET: Self-reset
LATCH 1

EVENTS: Disabled
Latch n type Latch n Latch n
set reset
Reset ON OFF
Dominant
OFF OFF
ON ON
OFF ON
Set ON OFF
Dominant
ON ON
OFF OFF
OFF ON
Range: FlexLogic operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
Latch n Latch n
on off
ON OFF
Previous Previous
State State
OFF ON
OFF ON
ON OFF
ON OFF
Previous Previous
State State
OFF ON
menu (see the Control Elements section
SETTING GROUPS
GROUPED ELEMENTS
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