Function blocking, Directional supervision, N table 72 – Basler Electric BE1-11t User Manual

Page 200: Table 72.), Ee table 72.)

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9424200995 Rev H

Table 72. Fuse Loss Logic Parameters

Input

True Condition

A

Positive-sequence volts greater than 8.8% of the nominal voltage; Detects minimum voltage is applied.

B

Positive-sequence amps greater than 8.8% of the nominal current; Detects minimum current is applied.

C

Negative-sequence volts greater than 25% of the pos-seq volts; Detects loss of 1 or 2 phase voltages.

D

Negative-sequence amps less than 17.7% of the pos-seq amps; Detects a normal current condition.

E

Positive-sequence volts less than 8.8% of the nominal voltage; Detects loss of three-phase voltage.

F

Positive-sequence amps less than 200% of the nominal current; Detects a normal load current condition.

G

Three-wire or four-wire sensing selected.

H

Positive-sequence volts greater than 85% of nominal voltage; Detects a restored voltage condition.

J

(B + S); Detects breaker position and nominal current condition.

K

(A * C * G * J * P); Detects when either one or two phases are lost.

L

(E * F * G * J); Detects when all three phases are lost.

M, N

Latches the 60FL output until the reset criteria are met.

P

(R+D); Logical OR of comparators R and D to detect a normal current condition.

R

Negative-sequence amps less than 15% of the nominal current; Detects a normal current condition.

S

Breaker Status is configured by the Breaker Status logic block. Information on setting up the breaker
status logic can be found in the

Breaker Monitoring

chapter. The Ignore Breaker Status setting is found

on the 60FL settings screen. (Enabled = 1, Disabled = 0)

Function Blocking

User selectable block settings determine how the 51/27R, 27, 59, 27X, and 59X protection functions
operate when a fuse loss condition exists. The Block Voltage Control (51/27) setting assumes that the
voltage is V

NOM

when Fuse Loss is true because the voltage measurement is not present or is unreliable. If

the input voltage is nominal, then voltage restraint and control have no effect. The Block Voltage settings
determine which voltage functions are blocked when the Fuse Loss logic is true.

Note

Protective elements blocked by 60FL should be set so that trip times
are 60 milliseconds or greater to assure proper coordination of
blocking.

Directional Supervision

The directional tests are also supervised by the fuse loss element. If the 60FL logic is true, then voltage
sensing was lost or is unreliable. Under this condition positive, negative, and zero-sequence directional
tests are disabled and their bits are cleared. There is no user setting to enable or disable this supervision.
Current polarization is not affected by the 60FL since it does not rely on voltage sensing. Similarly, zero-
sequence voltage polarization can be performed only if 3P4W sensing is selected. The following qualifiers
are applied to the voltage polarized ground direction element based on the user selected input quantity:

V0IN inputs:

Test: 60FL=FALSE & 3P4W=TRUE & (IN > minimum) & (IN > I1*8%) & (V0 > minimum)

V0IG inputs:

Test: 60FL=FALSE & 3P4W=TRUE & (IG > minimum) & (V0 > minimum)

VXIN inputs:

Test: (IG > minimum) & (IN > I1*8%) & (VX > minimum)

VXIG inputs:

Test: (IG > minimum) & (VX > minimum)

Fuse Loss (60FL)

BE1-11t

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