BE1_87_CDS
Basler-shaped current-differential element (ANSI 87) with dual-slope percentage restraint, minimum pickup, harmonic blocking and an unrestrained high-set.
When to use it
Use BE1_87_CDS when a transformer, bus or short line is protected by comparing the currents at the two ends of the zone, and the scheme needs percentage restraint so through-faults with CT error do not operate it.
Interface
The published port signature. This is the whole of what the block exposes to your program — the implementation body is not shown here and ships with the download.
Inputs
| Port | Type | Unit |
|---|---|---|
| ENABLE | BOOL | — |
| Iw1a | REAL | pu |
| Iw1b | REAL | pu |
| Iw1c | REAL | pu |
| Iw2a | REAL | pu |
| Iw2b | REAL | pu |
| Iw2c | REAL | pu |
| Slp | REAL | pu |
| SLP2 | REAL | pu |
| I_BRK | REAL | pu |
| I_MIN | REAL | pu |
| I_HS | REAL | pu |
| H2_PCT | REAL | % |
| H5_PCT | REAL | % |
| H2_BLK | REAL | % |
| H5_BLK | REAL | % |
| HARM_EN | BOOL | — |
| CT_OK | BOOL | — |
| BLK | BOOL | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| TRIP | BOOL | — |
| Idiff | REAL | pu |
| Ires | REAL | pu |
| TRIP_A | BOOL | — |
| TRIP_B | BOOL | — |
| TRIP_C | BOOL | — |
| OP_UNRES | BOOL | — |
| HARM_BLOCK | BOOL | — |
| BLOCKED | BOOL | — |
| MEAS_VALID | BOOL | — |
| ALM_CT_FAIL | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Supervised control write
BE1_87_CDS commands a real actuator. It is written to sit underneath your own interlock, permissive and protection logic — not to replace it. Commission it as you would any control block you wrote yourself.
Validation evidence
- Tests
- 11
- Simulated scans
- 49
- Simulator
- v0.1.0
Complete IEC 61131-3 implementation with a published test suite that runs on the vplant simulator. The counts above are that suite, executed on this build.
- Conforms to IEC 61131-3
- Conforms to IEC 61499
Download BE1_87_CDS — free
Create a free Ri Tech account to download the block. You get the Structured Text body, the Rockwell Add-On Instruction (.L5X), the Schneider Control Expert DFB (.XDB), PLCopen XML, the IEC 61499 function block type (.fbt) and the datasheet.
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Source is never published on this page. The implementation is released to a signed-in Ri Tech account — free of charge, but never anonymously.