Overview
The “Line differential protection” function is a selective short-circuit protection for overhead lines, cables, and busbars with single-side and multiside infeed in radial, looped, or meshed systems. It allows instantaneous tripping on 2 to 6 line ends if short circuits occur, works strictly phase-selectively, allows protection of a transformer in the protection range of the line, and becomes more sensitive when using charging-current compensation (Ic compensat.).
For more detailed information on “Line differential protection” function, refer to SIPROTEC 5 devices, V8.30 & higher manuals.
To see other supported functions, click here.
Structure/Embedding of the Function
Setting Parameters
General setting parameters
| Addr. | Parameter | C | Setting Options | Default Setting |
| General | ||||
| _:2311:1 | General:Mode | off on test |
off | |
| _:2311:102 | General:Min. current for release | 1 A @ 100 Irated | 0.000 A to 35.000 A | 0.000 A |
| 5 A @ 100 Irated | 0.00 A to 175.00 A | 0.00 A | ||
| 1 A @ 50 Irated | 0.000 A to 35.000 A | 0.000 A | ||
| 5 A @ 50 Irated | 0.00 A to 175.00 A | 0.00 A | ||
| 1 A @ 1.6 Irated | 0.000 A to 1.600 A | 0.000 A | ||
| 5 A @ 1.6 Irated | 0.000 A to 8.000 A | 0.000 A | ||
| _:2311:104 | General:Supervision Idiff | no yes: reporting only yes: block diff. prot. |
block diff. | |
Setting parameters for Stage I-DIFF
| Addr. | Parameter | C | Setting Options | Default Setting |
| I-DIFF | ||||
| _:3451:1 | I-DIFF:Mode | off on |
on | |
| _:3451:2 | I-DIFF:Operate & flt.rec. blocked | no yes |
no | |
| _:3451:27 | I-DIFF:Blk. w. inrush curr. detect. | no yes |
no | |
| _:3451:3 | I-DIFF:Threshold | 1 A @ 100 Irated | 0.100 A to 20.000 A | 0.300 A |
| 5 A @ 100 Irated | 0.50 A to 100.00 A | 1.50 A | ||
| 1 A @ 50 Irated | 0.100 A to 20.000 A | 0.300 A | ||
| 5 A @ 50 Irated | 0.50 A to 100.00 A | 1.50 A | ||
| _:3451:101 | I-DIFF:Thresh. switch onto fault | 1 A @ 100 Irated | 0.100 A to 20.000 A | 0.300 A |
| 5 A @ 100 Irated | 0.50 A to 100.00 A | 1.50 A | ||
| 1 A @ 50 Irated | 0.100 A to 20.000 A | 0.300 A | ||
| 5 A @ 50 Irated | 0.50 A to 100.00 A | 1.50 A | ||
| _:3451:102 | I-DIFF:Delay 1-phase pickup | 0.00 s to 0.50 s | 0.04 s | |
| _:3451:6 | I-DIFF:Operate delay | 0.00 s to 60.00 s | 0.00 s | |
Setting parameters for Stage I-DIFF Fast 2
| Addr. | Parameter | C | Setting Options | Default Setting |
| I-DIFF fast 2 | ||||
| _:18211:1 | I-DIFF fast 2:Mode | off on |
on | |
| _:18211:2 | I-DIFF fast 2:Operate & flt.rec. blocked | no yes |
no | |
| _:18211:3 | I-DIFF fast 2:Threshold | 1 A @ 100 Irated | 0.500 A to 100.000 A | 1.000 A |
| 5 A @ 100 Irated | 2.50 A to 500.00 A | 5.00 A | ||
| 1 A @ 50 Irated | 0.500 A to 100.000 A | 1.000 A | ||
| 5 A @ 50 Irated | 2.50 A to 500.00 A | 5.00 A | ||
| _:18211:101 | I-DIFF fast 2:Thresh. switch onto fault | 1 A @ 100 Irated | 0.500 A to 100.000 A | 1.000 A |
| 5 A @ 100 Irated | 2.50 A to 500.00 A | 5.00 A | ||
| 1 A @ 50 Irated | 0.500 A to 100.000 A | 1.000 A | ||
| 5 A @ 50 Irated | 2.50 A to 500.00 A | 5.00 A | ||
| _:18211:106 | I-DIFF fast 2:Delay 1- phase pickup | 0.00 s to 0.50 s | 0.04 s | |
Setting parameters for Stage I-DIFF Fast
| Addr. | Parameter | C | Setting Options | Default Setting |
| I-DIFF fast | ||||
| _:3481:1 | I-DIFF fast:Mode | off on |
on | |
| _:3481:2 | I-DIFF fast:Operate & flt.rec. blocked | no yes |
no | |
| _:3481:3 | I-DIFF fast:Threshold | 1 A @ 100 Irated | 0.800 A to 100.000 A | 1.000 A |
| 5 A @ 100 Irated | 4.000 A to 500.000 A | 5.000 A | ||
| 1 A @ 50 Irated | 0.800 A to 100.000 A | 1.000 A | ||
| 5 A @ 50 Irated | 4.000 A to 500.000 A | 5.000 A | ||
| _:3481:101 | I-DIFF fast:Thresh. switch onto fault | 1 A @ 100 Irated | 0.800 A to 100.000 A | 1.000 A |
| 5 A @ 100 Irated | 4.000 A to 500.000 A | 5.000 A | ||
| 1 A @ 50 Irated | 0.800 A to 100.000 A | 1.000 A | ||
| 5 A @ 50 Irated | 4.000 A to 500.000 A | 5.000 A | ||
| _:3481:106 | I-DIFF fast:Delay 1-phase pickup | 0.00 s to 0.50 s | 0.04 s | |
Setting parameters for Remote Tripping
| Addr. | Parameter | C | Setting Options | Default Setting |
| General | ||||
| _:5551:1 | Remote trip.:Mode | off on |
on | |
| _:5551:100 | Remote trip.:Transmit- ting | no yes |
yes | |
| _:5551:101 | Remote trip.:Receiving | yes report only |
yes | |
| Intertrip | ||||
| _:5551:103 | Remote trip.:Send delay | 0.00 s to 30.00 s | 0.02 s | |
| _:5551:104 | Remote trip.:Send prolongation | 0.00 s to 30.00 s | 0.00 s | |
Setting parameters in case of Transformer in Protection Range
| Addr. | Parameter | C | Setting Options | Default Setting |
| Transformer | ||||
| _:103 | Transformer:Voltage vector group nb. | 0 to 11 | 0 | |
| _:104 | Transformer:Current vector group nb. | 0 to 11 | 0 | |
| _:105 | Transformer:Residual curr. elimination | no yes |
||
Setting parameters for Charging-Current Compensation Ic-Compensation
| Addr. | Parameter | C | Setting Options | Default Setting |
| Ic-compensat. | ||||
| _:1 | Ic-compensat.:Mode | off on |
on | |
| _:101 | Ic-compensat.:Ic-stabiliza- tion/Ic-rated | 1.0 to 4.0 | 1.5 | |
| _:102 | Ic-compensat.:Total line length | 0.1 km to 1000.0 km | 100.0 km | |
Logic Diagrams & highlights
Differential Protection for a Line with 2 Ends
Differential Protection for a Line with 3 Ends
Differential Protection for a Line with 3 Ends with 2 Devices
Operate Curve of the Differential Protection
Approximation of the Current-Transformer Errors
Pickup Characteristic of the I-DIFF Stage
Pickup Characteristic of the I-DIFF fast 2 Stage
Logic of the Transmit Direction
Logic of the Receive Direction
Pickup Logic
Trip Logic
Differential Protection with 3 Devices for a Line with a Feeder
Logic for Logging off the Function
External Push-Button Wiring for Logging off the Local Line Differential Protection
External Switch Wiring for Logging off the Local Line Differential Protection
Ground Fault Outside of the Transforme
Charging-Current Compensation for a Line with 2 Ends (1-Phase System)
