SR

Set-dominant bistable — with both inputs asserted, SET wins.

Validated application blockIEC 61131-3 · StandardIEC 61131-3IEC 61499v1.0.0

When to use it

Use SR when a condition must latch and stay latched until deliberately cleared, and a simultaneous set and reset must resolve as SET — trip latches, safety-relevant annunciation.

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

PortType
S1BOOL
RBOOL

Outputs

PortType
Q1BOOL

IEC 61499 event interface

EI INIT, REQ·EO INITO, CNF

Validation evidence

Tests
3
Simulated scans
8
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 SR — 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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