Overview
The “Permissive overreaching transfer trip” scheme (POTT) is intended for two-terminal line applications only. It uses an over-reaching zone 2 distance element to essentially compare the direction to a fault at both the ends of the line. Ground directional overcurrent functions available in the relay can be used in conjunction with the zone 2 distance element to key the scheme and initiate its operation. This provides increased coverage for high resistance faults.
For more detailed information on “Permissive overreaching transfer trip” scheme (POTT), refer to GE, Universal Relay (UR) family of products, Version 8.0x manuals.
To see other supported elements, click here.
Setting Parameters
Modbus memory map for Setting parameters
| Products | Hex address | Register name | Range | Units | Step | Format | Default |
| D60, L90 | 6BF6 | POTT 1P Scheme Function | 0 to 1 | — | 1 | F102 | 0 (Disabled) |
| " | 6BF7 | POTT 1P Permissive Echo | 0 to 2 | — | 1 | F199 | 0 (Disabled) |
| " | 6BF8 | POTT 1P Rx Pickup Delay | 0 to 65.535 | s | 0.001 | F001 | 0 |
| " | 6BF9 | POTT 1P Trans Block Pickup Delay | 0 to 65.535 | s | 0.001 | F001 | 20 |
| " | 6BFA | POTT 1P Trans Block Reset Delay | 0 to 65.535 | s | 0.001 | F001 | 90 |
| " | 6BFB | POTT 1P Echo Duration | 0 to 65.535 | s | 0.001 | F001 | 100 |
| " | 6BFC | POTT 1P Echo Lockout | 0 to 65.535 | s | 0.001 | F001 | 250 |
| " | 6BFD | POTT 1P Line End Open Pickup Delay | 0 to 65.535 | s | 0.001 | F001 | 50 |
| " | 6BFE | POTT 1P Seal In Delay | 0 to 65.535 | s | 0.001 | F001 | 0 |
| " | 6BFF | POTT 1P Ground Directional Overcurrent Forward | 0 to 4294967295 | — | 1 | F300 | 0 |
| " | 6C01 | POTT 1P Number of Communication Bits | 0 to 2 | — | 1 | F198 | 0 (1) |
| " | 6C02 | POTT 1P Rx1 | 0 to 4294967295 | — | 1 | F300 | 0 |
| " | 6C04 | POTT 1P Rx2 | 0 to 4294967295 | — | 1 | F300 | 0 |
| " | 6C06 | POTT 1P Rx3 | 0 to 4294967295 | — | 1 | F300 | 0 |
| " | 6C08 | POTT 1P Rx4 | 0 to 4294967295 | — | 1 | F300 | 0 |
| " | 6C0A | POTT 1P Target | 0 to 2 | — | 1 | F109 | 0 (Self-reset) |
| " | 6C0B | POTT 1P Event | 0 to 1 | — | 1 | F102 | 0 (Disabled) |
| " | 6C0C | POTT 1P Echo Condition | 0 to 4294967295 | — | 1 | F300 | 0 |
| " | 6C0E | POTT 1P Scheme Block | 0 to 4294967295 | — | 1 | F300 | 0 |
| " | 6C10 | Reserved (22 items) | 0 to 1 | — | 1 | F001 | 0 |
| F102 | 0 = Disabled, 1 = Enabled | ||||||
| F109 | 0 = Self-reset, 1 = Latched, 2 = Disabled | ||||||
| F198 | 0 = 1, 1 = 2, 2 = 4 | ||||||
| F199 | 0 = Disabled, 1 = Enabled, 2 = Custom | ||||||
Logics & highlights
POTT scheme logic
