Overview
The “Voltage-restrained time overcurrent protection (VRPVOC)” function can be used as generator backup protection against short-circuits.
For more detailed information on “Voltage-restrained time overcurrent protection (VRPVOC)” 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 |
| Voltage-restrained time overcurrent protection | VRPVOC | I>/U< | 51V |
Signals & Setting Parameters
VRPVOC function block
VRPVOC Input signals
| VRPVOC Input signals | |||
| Name | Type | Default | Description |
| I3P | GROUP SIGNAL | – | Three phase group signal for current inputs |
| U3P | GROUP SIGNAL | – | Three phase group signal for voltage inputs |
| BLOCK | BOOLEAN | 0 | Block of function both stages |
| BLKOC | BOOLEAN | 0 | Block of voltage restraint overcurrent stage (ANSI 51V) |
| BLKUV | BOOLEAN | 0 | Block of under voltage function |
VRPVOC Output signals
| VRPVOC Output signals | |||
| Name | Type | Description | |
| TRIP | BOOLEAN | General trip signal | |
| TROC | BOOLEAN | Trip signal from voltage restrained overcurrent stage | |
| TRUV | BOOLEAN | Trip signal from undervoltage function | |
| START | BOOLEAN | General start signal | |
| STOC | BOOLEAN | Start signal from voltage restrained overcurrent stage | |
| STUV | BOOLEAN | Start signal from undervoltage function | |
VRPVOC Group settings (basic)
| VRPVOC Group settings (basic) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| Operation | Off On |
– | – | Off | Operation Off / On |
| StartCurr | 2.0 – 5000.0 | %IB | 1.0 | 120.0 | Start current level in % of IBase |
| Characterist | ANSI Ext. inv. ANSI Very inv. ANSI Norm. inv. ANSI Mod. inv. ANSI Def. Time L.T.E. inv. L.T.V. inv. L.T. inv. IEC Norm. inv. IEC Very inv. IEC inv. IEC Ext. inv. IEC S.T. inv. IEC L.T. inv. IEC Def. Time |
– | – | IEC Norm. inv. | Time delay curve type for 51V Voltage restrained overcurrent |
| tDef_OC | 0.00 – 6000.00 | s | 0.01 | 0.50 | Definite time delay for Over Current |
| k | 0.05 – 999.00 | – | 0.01 | 1.00 | Time multiplier for Inverse Definite Minimum Time curves |
| tMin | 0.00 – 60.00 | s | 0.01 | 0.05 | Minimum operate time for Inverse Definite Minimum Time curve |
| Operation_UV | Off On |
– | – | Off | Operation of under-voltage stage (ANSI 27) Off / On |
| StartVolt | 2.0 – 100.0 | %UB | 0.1 | 50.0 | Voltage for start of under-voltage stage in % of UBase |
| tDef_UV | 0.00 – 6000.00 | s | 0.01 | 1.00 | Definite time time delay when used for Under-Voltage |
| EnBlkLowV | Off On |
– | – | Off | Enable internal low voltage level blocking for Under-Voltage |
| BlkLowVolt | 0.0 – 5.0 | %UB | 0.1 | 3.0 | Internal low voltage level for blocking of UV in % of UBase |
VRPVOC Group settings (advanced)
| VRPVOC Group settings (advanced) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| VDepMode | Step Slope |
– | – | Slope | Voltage dependent mode OC (step, slope) |
| VDepFact | 5.0 – 100.0 | % | 0.1 | 25.0 | Start current level in % of pickup when U< 25% of UBase |
| UHighLimit | 30.0 – 100.0 | %UB | 0.1 | 100.0 | Voltage high limit setting in % of UBase |
VRPVOC Non group settings (basic)
| VRPVOC 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 |
VRPVOC Monitored data
| VRPVOC Monitored data | ||||
| Name | Type | Values (Range) | Unit | Description |
| IMAX | REAL | – | A | Maximum phase current magnitude |
| UUMIN | REAL | – | kV | Minimum ph-to-ph voltage magnitude |
Logics & highlights
Example for start level of the current variation as function of measured voltage magnitude in Slope mode of operation
Example for start level of the current variation as function of measured voltage magnitude in Step mode of operation
Simplified internal logic diagram for overcurrent function
Simplified internal logic diagram for undervoltage function
