Lineovrld - GE ALPS Instruction Manual

2.3 PROTECTION SETTINGS
If sufficient load current is flowing prior to the fault, there is no output from OR1, indicating that no charging current is
detected, and AND3 is not blocked, since there is no output from AND2. If an unbalanced fault subsequently occurs, FD
blocks AND1 to prevent an AND2 output. AND3 is allowed to produce an output when the remote breaker opens, provided
there is sufficient charging current to operate one or more of the three charging-current-detectors that are the inputs to
OR1. The capacitive charging current must be 60 milliamperes or more (secondary phase current) to assure operation of
ROD. If the fault is still present, as indicated by an output from OR3, a ROD trip is initiated following TL20 security time
delay setting.
2
1001: REMOTEOPEN - Select Remote Open Detector
Set REMOTEOPEN = YES if the remote open detection function is to be used, otherwise set REMOTEOPEN = NO.
1002: TL20PICKUP - Remote Open Detector Time Delay
TL20PICKUP the time required for a remote open trip to be initiated following opening of the remote breaker and subse-
quent detection of charging current flow. Longer settings will provide greater security but slower tripping and vice versa.
Use a TL20PICKUP setting that meets the specific application.
The Line Overload function consists of two overcurrent units, Level 1 and Level 2, with independent time delays. Level 1 is
intended to be used with the lower pickup and longer time delay. Level 2 is intended to be used with the higher pickup and
shorter time delay. The pickup and time delay settings should be based on short time and emergency loading situations for
the protected line.
1101: LINEOVERLD - Select Line Overload Protection
Set LINEOVERLD = YES if line overload protection is to be used, otherwise set LINEOVERLD = NO. If LINEOVERLD =
NO, ignore Protection Settings 1102 to 1105.
1102: LEVEL1PU - Level 1 Pickup Current
Use a LEVEL1PU setting that meets the specific application.
1103: LEVEL2PU - Level 2 Pickup Current
Use a LEVEL2PU setting that meets the specific application.
1104: LEVEL1TDLY - Level 1 Time Delay
Use a LEVEL1TDLY setting that meets the specific application.
1105: LEVEL2TDLY - Level 2 Time Delay
Use a LEVEL2TDLY setting that meets the specific application.
1201: PICKSCHEME - Select Scheme Logic
Any one of the following schemes can be selected:
1. STEPDST - step distance
2. PUTT - Permissive Underreaching Transfer Trip
3. POTT1 - Permissive Overreaching Transfer Trip (uses traditional transient blocking for current reversals)
4. POTT2 - Permissive Overreaching Transfer Trip (uses blocking functions to establish transient blocking)
5. HYBRID - Hybrid Scheme (uses channel repeat circuitry and weak infeed tripping if desired)
6. BLOCK - A directional comparison Blocking scheme
7. HYBRIDP - Hybrid scheme with Phase Identified channel logic (for both two and four channel schemes)
Set PICKSCHEME to the desired scheme.
2-32 ALPS Advanced Line Protection System
2 CALCULATION OF SETTINGS

2.3.13 LINEOVRLD

2.3.14 SCHEME
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