Overview
To achieve fast fault clearance of earth faults on the part of the line not covered by the instantaneous step of the residual overcurrent protection, the directional residual overcurrent protection can be supported with a logic that uses communication channels: the “Scheme communication logic for residual overcurrent protection (ECPSCH).
For more detailed information on this 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 |
| Scheme communication logic for residual overcurrent protection | ECPSCH | – | 85 |
Signals & Setting Parameters
ECPSCH function block
ECPSCH Input signals
| ECPSCH Input signals | |||
| Name | Type | Default | Description |
| BLOCK | BOOLEAN | 0 | Block of function |
| BLKTR | BOOLEAN | 0 | Signal for blocking trip due to communication logic |
| BLKCS | BOOLEAN | 0 | Signal for blocking CS in Overreach and Blocking schemes |
| CSBLK | BOOLEAN | 0 | Reverse residual overcurrent signal for Carrier Send |
| CACC | BOOLEAN | 0 | Signal to be used for tripping by Communication Scheme |
| CSOR | BOOLEAN | 0 | Overreaching residual overcurrent signal for Carrier Send |
| CSUR | BOOLEAN | 0 | Underreaching residual overcurrent signal for Carrier Send |
| CR | BOOLEAN | 0 | Carrier Receive for Communication Scheme Logic |
| CRG | BOOLEAN | 0 | Carrier guard signal received |
ECPSCH Output signals
| ECPSCH Output signals | |||
| Name | Type | Description | |
| TRIP | BOOLEAN | Trip signal by communication scheme logic | |
| CS | BOOLEAN | Carrier Send by Communication Scheme Logic | |
| CRL | BOOLEAN | Carrier Receive from Communication Scheme Logic | |
| LCG | BOOLEAN | loss of carrier guard signal | |
ECPSCH Group settings (basic)
| ECPSCH Group settings (basic) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| Operation | Off On |
– | – | Off | Operation Off / On |
| SchemeType | Off Intertrip Permissive UR Permissive OR Blocking |
– | – | Permissive UR | Scheme type, Mode of Operation |
| tCoord | 0.000 – 60.000 | s | 0.001 | 0.035 | Communication scheme coordination time |
| tSendMin | 0.000 – 60.000 | s | 0.001 | 0.100 | Minimum duration of a carrier send signal |
ECPSCH Group settings (advanced)
| ECPSCH Group settings (advanced) | |||||
| Name | Values (Range) | Unit | Step | Default | Description |
| Unblock | Off NoRestart Restart |
– | – | Off | Operation mode of unblocking logic |
| tSecurity | 0.000 – 60.000 | s | 0.001 | 0.035 | Security timer for loss of carrier guard detection |
Logics & highlights
Simplified logic diagram for blocking scheme
Simplified logic diagram for Permissive under/overreaching scheme
Guard signal logic with unblocking scheme
