GE MOV 2000, Инструкция по эксплуатации

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2. OPERATION PRINCIPLES
14 MIV Digital Multifunctional Protective Relay GEK-106271
2.4. CONTROL
2.4.1. SETTINGS TABLES
The MOV incorporates three independent settings tables, stored in a non volatile memory, so that they are
maintained event without power supply. Only one table is active at each time, and it is the one used by the system
to operate.
MOV settings are divided in generic groups (General settings, Switchgear settings, Oscillography masks and
Function Permissions). These are common to all setting tables. Other settings are separate for each table.
There is a setting called “ACTIVE TABLE” that allows choosing the settings table that will be active each time.
There is a way to switch the settings table using up to 2 digital inputs, named “TABLE SELECTION 0” and “TABLE
SELECTION 1”. These allow up to 4 combinations, from 0 to 3. For applications requiring a lower number of
tables (up to 2), we can use only one digital input.
The selected combination is obtain from the binary codification of the above referred inputs (please refer to the
following table). 0 means selecting the table shown on the “ACTIVE TABLE” setting. Numbers 1 to 3 select tables
1 to 3 (we must keep in mind that table 3 is always associated with cold load pickup, and has maximum priority.
Please refer to section 2.4.5.).
Number Table Selection 1 Table Selection 2 Active Table
0 0 0 Selected by setting
1 0 1 1
2 1 0 2
3 1 1 3
NOTE: If the active table is controlled using these inputs, this selection will have priority over the “ACTIVE TABLE”
setting, and the table used will be determined by the status of the digital inputs.
2.4.2. TIME SYNCHRONIZATION
The MOV system includes an input for time synchronization. This input requires the connection of a device
to supply a demodulated IRIG-B output. In this way co-ordinated universal time is measured to a high degree of
precision and this makes it possible to tag the events generated by the unit with a resolution of one millisecond.
The use of this input makes it possible to correlate data obtained from different units thanks to
synchronization with GPS satellites. In this way it is possible to obtain very useful information for analysis, cross-
referencing the information provided by different units for a given incident.
Alternatively, it is possible to synchronise units by means of communications, using the GE-LOCAL
communications software, or manually by means of the MMI. If the IRIG-B input is used it has priority over time
setting by communications, since the time read by IRIG-B is much more accurate.