ABB REG670 Applications Manual

OpModeZ2: Zone 2 distance element can be selected as Off, PP Loops or
EnhancedReach.
Z2Fwd: Zone 2 forward reach in percentage. It is recommended to set zone 2 forward
reach to 125% of transformer impedance.
Z2Rev: Zone 2 reverse reach in percentage. It is recommended to give limited reverse
reach to ensure operation for close in fault and to minimize area covered in R-X plane.
A setting of 8%. is recommended.
tZ2: Zone 2 operate time delay in seconds. Time delay should be provided in order to
coordinate with zone 1 element provided for the outgoing line.
Zone 3
Zone 3 in ZGVPDIS function has offset mho characteristic and it can evaluate three
phase-to-phase impedance measuring loops or EnhancedReach loop
OpModeZ3: Zone 3 distance element can be selected as Off, PP Loops or
EnhancedReach. It is recommended to select EnhancedReach setting.
Z3Fwd: Zone 3 forward reach in percentage. It is recommended to set zone 3 forward
reach to coordinate with the longest time delay for the transmission line protection
connected to the generating substation bus. Alternatively it can be set to 80% of the
load impedance considering maximum short time over load of the generator.
Z3Rev: Zone 3 reverse reach in percentage. It is recommended to give limited reverse
reach to ensure operation for close in faults and to minimize area covered in R-X
plane. A setting of 8%. is recommended.
tZ3: Zone 3 operates time delay in seconds. Time delay is provided in order to
coordinate with slowest circuit backup protection or slowest local backup for faults
within zone 3 reach. A safety margin of 100 ms should be considered.
8.9.3.2 Load encroachment
The settings involved in load encroachment feature are:
ArgLd: Angle in degrees of load encroachment characteristics
RLd: Positive sequence resistance in per unit
The procedure of calculating the settings for load encroachment consists basically of
defining load angle ArgLd and resistive blinder RLd. The load encroachment logic can
be enabled for zone 2 and zone 3 elements. For zone 2, the load encroachment can be
enabled or disabled using the LoadEnchModZ2 setting by selecting either On or Off.
Similarly for zone 3 load encroachment can be enabled or disabled using the
LoadEnchModZ3 setting by selecting either On or Off.
1MRK 502 071-UEN - Section 8
Impedance protection
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062 315
Application manual

ABB REG670 Specifications

General

Brand	ABB
Model	REG670
Category	Protection Device
Language	English