GE LPS-D Instruction Manual page 23

1 PRODUCT DESCRIPTION
Table 1–2: LPS-D MEASUREMENT FUNCTIONS
Zone or Type
Zone 1
Zone 2 (Pilot Zone)
Zone 3
Zone 4
Out of Step Blocking (OSB)
Overcurrent Backup
Overcurrent Supervision
Fault Detector
Line-Pickup Overcurrent
Remote-Open Detectors
Line-Overload Detectors
The Zone 4 variable-mho distance functions can be reversed in direction when a reversed or blocking function
is required. When the POTT2, Blocking or Hybrid scheme is selected, Zone 4 is automatically set to the
reverse direction, because these schemes require a reverse-looking blocking function. The Zone 4 phase and
ground distance functions are provided with independent timers for time delayed backup protection. Revision B
models also have the ability to use Zone 4 ground quadrilateral distance functions for time-delayed backup
protection.
GE Power Management
Functions
• 3 Variable-Mho phase distance functions
• 3 Variable-Mho ground distance functions
or
3 Reactance ground distance functions with "adaptive reach" Mho
supervision or 3 Quadrilateral ground distance functions (Revision B
relays only)
• 3 Variable-Mho phase distance functions
• 3 Variable Mho ground-distance functions
and/or
Ground directional-overcurrent functions consisting of:
IPT: Ground Trip overcurrent
NT: Negative Sequence Directional Trip
IPB: Ground Block overcurrent
NB: Negative Sequence directional block
or
3 Quadrilateral ground distance functions (Revision B relays only)
• 3 Variable-Mho phase-distance functions
• 3 Variable-Mho ground-distance functions, or
3 Quadrilateral ground distance functions (Revision B relays only)
• 3 Reversible variable-Mho phase-distance functions
• 3 Reversible variable-Mho ground-distance functions
3 Variable-Mho phase-distance functions
50 — Phase-overcurrent direct trip (directional or nondirectional
50G — Ground-overcurrent direct trip (directional or nondirectional)
51G — Ground time-overcurrent direct trip (directional or nondirectional)
IT — Trip-supervision overcurrent
IB — Block-supervision overcurrent
FD
I1
ROD
Level 1 Overcurrent
Level 2 Overcurrent
LPS-D Line Protection System
1.2 INTRODUCTION
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