GE Multilin DTP-B, Инструкция по эксплуатации

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4. FUNCTIONS DESCRIPTION
GEK-106243E DTP Digital Transformer Protection 4-1
4. FUNCTIONS DESCRIPTION
4.1 PROTECTION FUNCTIONS
The DTP has two differential protection functions:
•
Function 87 with percentage restraint and harmonic restraint (second and fifth harmonic).
•
Programmable instantaneous protection (87B) for differential current.
Their operation and application is described in sections 2 and 3.
The percentage restraint characteristic is composed of two protection zones. The inflexion point between them,
and the different slopes, can be configured by settings. If only one protection zone is required, the same slope
must be configured for both zones.
4.2 MONITORING AND REGISTERING FUNCTIONS
4.2.1 MEASUREMENT
The DTP relay can measure the following magnitudes:
•
Line current (module and argument for each phase and winding)
•
Differential and through current for each phase.
•
Second and fifth harmonic current for each phase.
These measurements can be accessed either locally, on the liquid crystal display (LCD) on the front of the relay,
or via the GE_LOCAL communication software, in the measurements screen. The line current measures offered
by the equipment are affected by the CT ratios defined in the general settings (CT RATIO X DEV).
The line current arguments take as reference phase A (0º) of the transformer’s primary winding. Therefore, this
phase must be present so that the measurements of the arguments are coherent .
4.2.2 LED INDICATORS
An internal states matrix stores the digital information for all the units (inputs, pickups, alarms, etc.). The digital
signals on this matrix are grouped in groups of 16 signals; up to a total of 10 groups; the final group corresponds
to the 16 AND gates definable using the programmable logic of GE_INTRO configuration software. Therefore, the
selected signals, or the result of an AND gate from a group, can be taken to this last AND1....AND16 group.
The DTP unit has a total of 17 LED indicators, one fixed bicolour assigned to the critical alarm function of the unit
and 16 red LED indicators, arranged in one column. They can be configured using the GE-INTRO configuration
software to any of the user definable alarms (32 protection alarms and 16 communication alarms for 2 and 3
windings models, or 16 protection alarms and 16 communication alarms for 4 windings models) assigned from
among the protection and communication states. To define each alarm, the user can use 16 inputs OR gates. All
the inputs to an OR gate must belong to the same group in the states matrix. Similarly, each LED can be
configured to have memory in the absence of auxiliary power supply (the status of the LED with memory is
registered on the EEPROM memory). They can also be configured to blink when turned on.