Basler BE1-DFPR Instruction Manual Download

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BE1-DFPR Functional Description

3-12

to 150 amperes in 1 ampere increments for a 5 ampere sensing input range and 0.1 to 30 amperes
in 0.02 ampere increments for a 1 ampere sensing input range.

Neutral settings adjustable over the range of 0.5 to 99 amperes in 0.1 ampere increments and 100
to 150 amperes in 1 ampere increments for a 5 ampere sensing input range and 0.1 to 30 amperes
in 0.02 ampere increments for a 1 ampere sensing input range.

Time delay adjustable over the range of 0.03 to 5.00 seconds for both the 50T and 50TN.

FREQUENCY TRIPPING AND RESTORATION

Underfrequency tripping function provides feeder tripping if the monitored system frequency remains below
the user defined 81T trip setting for a period of time 81 TTD (also defined by the user during the setting
procedure). This function also can restore the circuit (close the breaker) when the system frequency has
returned to normal and stabilized for the duration of 81 RTD (a second user defined frequency and time
period). The restore function may be inhibited with one of the user programmable inputs if selected from
the PROGRAMMABLE INPUTS screen under REVIEW/EDIT SETTINGS menu as described in publication
9 2315 00 991,

Terminal Displays and Settings. Operation of this function is inhibited if the monitored

system voltage is less than a user defined level, 81 UV INH.

UNDERVOLTAGE TRIPPING

Undervoltage tripping function provides tripping of the feeder if the monitored voltage of any one phase (A,
B, and C) voltage remains below the user defined 27 pickup trip setting for a period 27TD (also defined by
the user during the setting procedure). The 27 trip function is instantaneously reset when all phase voltages
are above the 27 pickup setting. A minimum voltage level of ten volts prevents tripping for blown potential
transformer fuses. The undervoltage function is inhibited if the sensing voltage is less than 10.0 volts. A
27TD setting of 0.0 inhibits the 27 function.

OVERVOLTAGE TRIPPING

Overvoltage tripping function provides tripping of the feeder if the monitored voltage of any one phase (A,
B, and C) voltage remains above the user defined 59 pickup trip setting for a period 59TD (also defined by
the user during the setting procedure). The 59 trip function is instantaneously reset when all phase voltages
are below the 59 pickup setting. A 59TD setting of 0.0 inhibits the 59 function.

TRIPPING LOGIC

All protective functions (51P, 51N, 50P, 50N, 50TP, 50TN, 81, 59, and 27) can be configured internally to
trip the breaker. The block tripping function is configured to provide selective blocking of tripping at user
defined points in the fault clearing sequence by the following:

Either or all of the phase instantaneous overcurrent elements

Neutral instantaneous overcurrent element

Under/Overvoltage function (27/59)

Underfrequency function (81)

This determination is made during the setting process for the relay from the communication port using the
TRIPPING LOGIC screens under the REVIEW/EDIT SETTINGS menu as described in publication 9 2315
00 991,

Terminal Displays and Settings.

Selected elements can be blocked from tripping by two contact inputs from the SCADA system.

Block trip contact (BT1) blocks tripping by the neutral instantaneous, neutral fixed time, and neutral time
overcurrent elements (50N, 50TN, and 51N).

Block trip contact (BT2) blocks tripping by all of the fixed time overcurrent elements (50TA, 50TB, 50TC,