GE DBF, Instructions Manual

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3. SETTINGS
GEK-106168E DBF Breaker Failure Protection 19
COMMENTS ON SETTINGS:
1. The Identification setting allows the user to input a name for the unit (for example the name of the line or
feeder) with a maximum of 20 ASCII characters.
2. The Active Table setting allows selecting the table to be active during normal operation among the three
tables available on the DBF. This selection can also be done by means of digital inputs configured for this
purpose. The table input selection has priority over the table setting selection (if the input has been configured
to perform change of tables).
3. To set the breaker monitoring function it is necessary to set first the kI2t OP. Mode setting. If this is selected
as "measured" no other setting is required, since the time used for the calculation is the time taken by the unit
during the interval: trip order-52/b contact to close. If the “fixed” mode is selected it is necessary to set then the
kI2t Integration Time. In this case the time used will be always the set time (should be the rated operating
time of the circuit breaker provided by the manufacturer).
4. The Pre-Fault Cycles to be shown in every oscillography record may be adjusted from two to ten (2-10). In
any case the total number of cycles for any oscillography record is 66, regardless of pre-fault cycles setting.
5. The difference between the function permission and permitted trips settings is:
•
The function permission setting enables or disables the function
•
The trip permission setting allows to enable or disable any specific function to trip, but keeping always
active the function, providing thus capability to generate events, alarms and signals.
6. The overcurrent ranges shown in Table 3 correspond to models of 1-12A for phase and 0.5-6A for ground for
5A rated CT’s. Only PH Lo-Set Pickup, PH Hi-Set Pickup and Neutral Pickup settings change with the
range.
7. Sometimes the names used to describe the settings for both the local HMI and the communications program
are short or abbreviated. This is because of the space limitation imposed by text windows in the program.