Definitive Zone (Def) - ABB RELION REB500 Technical Manual

1MRK 505 406-UEN B
• Delay (1) < Delay (2) < Delay (3) < Delay (4) < Delay(Def)
• Delay (OR) < Delay (2)
When grading the operating times of several distance relays, the minimum grading time
should not be less than the sum of the circuit-breaker operating time plus 150 ms (reset time +
operating time of the measuring system + safety margin).
Recommended timer settings:
• Zone 1: normally instantaneous
• Zone 2:
arc extinction time, signal transmission time and a tolerance margin, which amounts to
about 0.25 to 0.5 s. The tolerance includes an allowance for sequential trip-ping.
• Zone 3:
• Zone 4:
Special cases may require settings, which deviate considerably from the above
recommendations.
The time steps of zones (1 to 4) must have settings less than
5.1.6.4

Definitive zone (Def)

The definitive (or fifth) zone is subject to the same parameters as the underimpedance
starters (that is,
The corresponding time step is defined by the parameter
IEC19000413 V1 EN-US
Figure 12:
Bay protection functions REB500
Technical manual
Delay (2) is normally set to the sum of relay and circuit breaker operating times,
Delay (3) is set to about 2 × Delay (2) .
Delay (4) or Delay(Def) is normally set to at least 4 × Delay (2) .
XA , XB , RA , RB , RLoad and AngleLoad ).
X
o
27
-RLoad
-RB
Definitive zone characteristic
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Delay (Def) .
XA
RLoad RA
(In tripping
o
27
direction)
-XB
18000011-IEC19000413-1-en.vsdx
Bay protection functions
Delay(Def) .
GUID-42A75BFC-871D-41BB-A9C0-327B47EE2AB2 v1
Load Angle
R
Section 5
47