Overview
When a power line is taken out of service for maintenance and the line disconnector is opened in multi-breaker arrangements the voltage transformers will mostly be outside on the disconnected part. The primary line distance protection will thus not be able to operate and must be blocked. The “Stub protection (STBPTOC)” function covers the zone between the current transformers and the open disconnector. The three-phase instantaneous overcurrent function is released from a normally open, NO (b) auxiliary contact on the line disconnector.
For more detailed information on “Stub protection (STBPTOC)” function, refer to ABB, Relion 670 Series manuals.
To see other supported functions, click here.
Function Identification
| Function description | IEC 61850 identification |
IEC 60617 identification |
ANSI/IEEE C37.2 device number |
| Stub protection | STBPTOC | 3I>STUB | 50STB |
Signals & Setting Parameters
STBPTOC function block
STBPTOC Input signals
| STBPTOC Input signals | |||
| Name | Type | Default | Description |
| I3P | GROUP SIGNAL | – | Three phase currents |
| BLOCK | BOOLEAN | 0 | Block of function |
| BLKTR | BOOLEAN | 0 | Block of trip |
| RELEASE | BOOLEAN | 0 | Release of stub protection |
STBPTOC Output signals
| STBPTOC Output signals | |||
| Name | Type | Description | |
| TRIP | BOOLEAN | General trip | |
| START | BOOLEAN | General start | |
STBPTOC Group settings (basic)
| STBPTOC Group settings (basic) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| Operation | Off On |
– | – | Off | Operation Off / On |
| ReleaseMode | Release Continuous |
– | – | Release | Release of stub protection |
| I> | 5 – 2500 | %IB | 1 | 200 | Operate current level in % of IBase |
STBPTOC Group settings (advanced)
| STBPTOC Group settings (advanced) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| tDelay | 0.000 – 60.000 | s | 0.001 | 0.000 | Time delay |
STBPTOC Non group settings (basic)
| STBPTOC Non group settings (basic) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| GlobalBaseSel | 1 – 12 | – | 1 | 1 | Selection of one of the Global Base Value groups |
STBPTOC Monitored data
| STBPTOC Monitored data | ||||
| Name | Type | Values (Range) | Unit | Description |
| IL1 | REAL | – | A | Current in phase L1 |
| IL2 | REAL | – | A | Current in phase L2 |
| IL3 | REAL | – | A | Current in phase L3 |
Logics & highlights
Simplified logic diagram for Stub protection
