Phase Preference Logic Ppl2Phiz - ABB RELION 670 SERIES Applications Manual

Line distance protection

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1MRK 506 369-UUS -

Line distance protection REL670 2.2 ANSI

Application manual

impedance grounded system, the voltage drop is big and the setting can typically be set to

70% of base voltage (VBase)

PU27PP: The setting of the phase-to-phase voltage level (line voltage) which is used by

the evaluation logic to verify that a fault exists in two or more phases. The voltage must

be set to avoid that a partly healthy phase-to-phase voltage, for example, B-C for a A-B

fault, picks-up and gives an incorrect release of all loops. The setting can typically be 40

to 50% of rated voltage (VBase) divided by √3, that is 40%.

3V0PU: The setting of the residual voltage level (neutral voltage) which is used by the

evaluation logic to verify that an ground-fault exists. The setting can typically be 20% of

base voltage (VBase).

Pickup_N: The setting of the residual current level (neutral current) which is used by the

evaluation logic to verify that a cross-country fault exists. The setting can typically be

20% of base current (IBase) but the setting shall be above the maximum current generated

by the system grounding. Note that the systems are high impedance grounded which

means that the ground-fault currents at ground-faults are limited and the occurring IN

above this level shows that there exists a two-phase fault on this line and a parallel line

where the IN is the fault current level in the faulty phase. A high sensitivity need not to be

achieved as the two-phase fault level normally is well above base current.

tIN: The time delay for detecting that the fault is cross-country. Normal time setting is 0.1

tVN: The time delay for a secure VN detecting that the fault is an ground-fault or double

ground-fault with residual voltage. Normal time setting is 0.1 - 0.15 s.

tOffVN: The VN voltage has a reset drop-off to ensure correct function without timing

problems. Normal time setting is 0.1 s

Phase preference logic PPL2PHIZ

Identification

Function description

Phase preference logic

The Phase preference logic function PPL2PHIZ provides a supplementary phase selection

to the High speed distance protection ZMFPDIS (21). The application is for resonance

Impedance protection

identification

ANSI/IEEE C37.2

device number