Table of Contents
Advertisement
2.3 PROTECTION SETTINGS
2 CALCULATION OF SETTINGS
Angles A, B and C are determined as a function of the reach (Zc) of the coordinating zone, the maximum load
flow (minimum Zload) and the fastest swing (first slip cycle). Angle A in the figure is selected via the ZxPCHA-
RANG (x = 2, 3 or 4) setting and determines the shape of the coordinating zone characteristic. Angle B is
selected via the MOBCHARANG setting and determines the shape of the MOB characteristic. Angle B should
be set so that the time for the fastest swing to traverse from angle B to angle A is not less than 30 milliseconds.
In addition, the A and B angle settings must be selected so that the difference between angle B and angle C is
never less than 20°. Note that angle C is determined as a function of the minimum load impedance (Zload) and
2
the reach (Zc) of the coordinating zone. Load flow and stability studies may have to be run to determine the
settings necessary to establish out-of-step blocking.
1601: MOBZONE - Coordinating Zone
Set MOBZONE to select a coordinating zone per the criteria described above.
1602: MOBCHARANG - MOB Characteristic Angle
Use the criteria described above to select an appropriate MOBCHARANG setting.
1603: BLOCKWHAT - Functions to Block during Out-of-Step Tripping
BLOCKWHAT is used to select which of the following are to be blocked during an out-of-step condition:
1. BLKALL - Block all tripping regardless of what operated to initiate the trip.
2. BLKDIST - Block tripping for operation of any of the distance functions.
3. BLKPHAS - Block tripping by any of the phase distance functions.
4. BLKNONE - allow tripping for any trip condition.
1604: BLOCKZ1 - Block All Zone 1 Functions
Set BLOCKZ1 = YES to block tripping by any of the Zone 1 distance functions, otherwise set BLOCKZ1 = NO.
1605: BLOCKZ2 - Block All Zone 2 Functions
Set BLOCKZ2 = YES to block tripping by any of the Zone 2 distance functions, otherwise set BLOCKZ2 = NO.
1606: BLOCKZ3 - Block All Zone 3 Functions
Set BLOCKZ3 = YES to block tripping by any of the Zone 3 distance functions, otherwise set BLOCKZ3 = NO.
1607: BLOCKZ4 - Block All Zone 4 Functions
Set BLOCKZ4 = YES to block tripping by any of the Zone 4 distance functions, otherwise set BLOCKZ4 = NO.
2.3.18 RECLOSER
The LPS-D is available with an optional recloser, described in Section 1.10: RECLOSER (OPTIONAL) on page
1–42. Note that if another relaying system is going to be used with or without the LPS-D to control the recloser,
then that relaying system must be capable of supplying a 1PRI (single phase reclose) and a 3PRI (three phase
reclose) input to the recloser. The following settings must be made when the recloser is supplied.
1801: RECLMODE - Select Reclosing Option
Set one of the following reclosing options:
1. NONE - no reclosing selected. The three phase trip enable output is not enabled at this time.
2-
LPS-D Line Protection System
GE Power Management
42
Advertisement
Table of Contents
