Introduction To Elements - GE t60 Instruction Manual

5 SETTINGS
SETTINGS
TRANSDUCER I/O
SETTINGS
TESTING
In the design of UR relays, the term "element" is used to describe a feature that is based around a comparator. The com-
parator is provided with an input (or set of inputs) that is tested against a programmed setting (or group of settings) to deter-
mine if the input is within the defined range that will set the output to logic 1, also referred to as "setting the flag". A single
comparator may make multiple tests and provide multiple outputs; for example, the time overcurrent comparator sets a
Pickup flag when the current input is above the setting and sets an Operate flag when the input current has been at a level
above the pickup setting for the time specified by the time-current curve settings. All comparators, except the Digital Ele-
ment which uses a logic state as the input, use analog parameter actual values as the input.
Elements are arranged into two classes, GROUPED and CONTROL. Each element classed as a GROUPED element is
provided with six alternate sets of settings, in setting groups numbered 1 through 6. The performance of a GROUPED ele-
ment is defined by the setting group that is active at a given time. The performance of a CONTROL element is independent
of the selected active setting group.
The main characteristics of an element are shown on the element logic diagram. This includes the input(s), settings, fixed
logic, and the output operands generated (abbreviations used on scheme logic diagrams are defined in Appendix F).
Some settings for current and voltage elements are specified in per-unit (pu) calculated quantities:
pu quantity = (actual quantity) / (base quantity)
• For current elements, the 'base quantity' is the nominal secondary or primary current of the CT. Where the current
source is the sum of two CTs with different ratios, the 'base quantity' will be the common secondary or primary current
GE Multilin
REMOTE DEVICES
REMOTE INPUTS
REMOTE OUTPUTS
DNA BIT PAIRS
REMOTE OUTPUTS
UserSt BIT PAIRS
RESETTING
DIRECT INPUTS
DIRECT OUTPUTS
DCMA INPUTS
RTD INPUTS
TEST MODE
FUNCTION: Disabled
TEST MODE INITIATE:
On
FORCE CONTACT
INPUTS
FORCE CONTACT
OUTPUTS
T60 Transformer Management Relay
5.1 OVERVIEW
See page 5–132.
See page 5–133.
See page 5–134.
See page 5–135.
See page 5–135.
See page 5–135.
See page 5–135.
See page 5–139.
See page 5–140.
See page 5–141.
See page 5–141.
See page 5–141.
See page 5–142.

5.1.2 INTRODUCTION TO ELEMENTS

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