r_20261029_190447_1fc8

done

drawing: drawing.png
reference: none
at: 2026-10-29T19:04:47Z

Summary

Single points of failure

No single point of failure: no one component failing on its own cuts the supply.

Pairs

36 pairs: the supply is lost only if both components of a pair fail together.

{CB-735-11, CB-735-12}
{CB-735-11, CT-735-12}
{CB-735-11, DS-735-12A}
{CB-735-11, DS-735-12B}
{CB-735-11, OE-TR-02}
{CB-735-11, TR-02}
{CB-735-12, CT-735-11}
{CB-735-12, DS-735-11A}
{CB-735-12, DS-735-11B}
{CB-735-12, OE-TR-01}
{CB-735-12, TR-01}
{CT-735-11, CT-735-12}
{CT-735-11, DS-735-12A}
{CT-735-11, DS-735-12B}
{CT-735-11, OE-TR-02}
{CT-735-11, TR-02}
{CT-735-12, DS-735-11A}
{CT-735-12, DS-735-11B}
{CT-735-12, OE-TR-01}
{CT-735-12, TR-01}
{DS-735-11A, DS-735-12A}
{DS-735-11A, DS-735-12B}
{DS-735-11A, OE-TR-02}
{DS-735-11A, TR-02}
{DS-735-11B, DS-735-12A}
{DS-735-11B, DS-735-12B}
{DS-735-11B, OE-TR-02}
{DS-735-11B, TR-02}
{DS-735-12A, OE-TR-01}
{DS-735-12A, TR-01}
{DS-735-12B, OE-TR-01}
{DS-735-12B, TR-01}
{OE-TR-01, OE-TR-02}
{OE-TR-01, TR-02}
{OE-TR-02, TR-01}
{TR-01, TR-02}

Click a set to highlight its components on the drawing and in the block diagram; click it again to clear.

Drawing and graph

block (can fail)perfect connectorin a cut-set difference show all connections

Hover a box to see its own connections.

Page 1

Not on the drawing

node	type	connected to	why
`OE-TR-01`	other	DS-735-11B, TR-01	Spec requires one operating-error block per transformer path.
`OE-TR-02`	other	DS-735-12B, TR-02	Spec requires one operating-error block per transformer path.
`OE-315-111`	other	DS-315-111A, CB-315-111	Spec requires one operating-error block per 315 kV branch.
`OE-315-112`	other	DS-315-112A, CB-315-112	Spec requires one operating-error block per 315 kV branch.
`OE-315-121`	other	DS-315-121A, CB-315-121	Spec requires one operating-error block per 315 kV branch.
`OE-315-122`	other	DS-315-122A, CB-315-122	Spec requires one operating-error block per 315 kV branch.

Block diagram

Series runs left to right; parallel branches stack.

Run r_20261029_190447_1fc8 · from drawing.png · 32 blocks · 0 single points of failure. Drawn in BlockSim's RBD layout so it can be rebuilt there block for block; this is a picture, not a BlockSim file. The machine-readable export is the Open-PSA fault tree.

Nested view

DS-735-11A→CB-735-11→CT-735-11→DS-735-11B→OE-TR-01→TR-01→

DS-315-111A→OE-315-111→CB-315-111→CT-315-111→DS-315-111B

DS-315-112A→OE-315-112→CB-315-112→CT-315-112→DS-315-112B

DS-735-12A→CB-735-12→CT-735-12→DS-735-12B→OE-TR-02→TR-02→

DS-315-121A→OE-315-121→CB-315-121→CT-315-121→DS-315-121B

DS-315-122A→OE-315-122→CB-315-122→CT-315-122→DS-315-122B

Cut sets

Reference: none

No verdict: nothing was compared with a reference. These are the model's own cut sets.

This model

Minimal cut sets up to order 3. Click an order to show or hide it.

Order 2 (36)

{CB-735-11, CB-735-12}
{CB-735-11, CT-735-12}
{CB-735-11, DS-735-12A}
{CB-735-11, DS-735-12B}
{CB-735-11, OE-TR-02}
{CB-735-11, TR-02}
{CB-735-12, CT-735-11}
{CB-735-12, DS-735-11A}
{CB-735-12, DS-735-11B}
{CB-735-12, OE-TR-01}
{CB-735-12, TR-01}
{CT-735-11, CT-735-12}
{CT-735-11, DS-735-12A}
{CT-735-11, DS-735-12B}
{CT-735-11, OE-TR-02}
{CT-735-11, TR-02}
{CT-735-12, DS-735-11A}
{CT-735-12, DS-735-11B}
{CT-735-12, OE-TR-01}
{CT-735-12, TR-01}
{DS-735-11A, DS-735-12A}
{DS-735-11A, DS-735-12B}
{DS-735-11A, OE-TR-02}
{DS-735-11A, TR-02}
{DS-735-11B, DS-735-12A}
{DS-735-11B, DS-735-12B}
{DS-735-11B, OE-TR-02}
{DS-735-11B, TR-02}
{DS-735-12A, OE-TR-01}
{DS-735-12A, TR-01}
{DS-735-12B, OE-TR-01}
{DS-735-12B, TR-01}
{OE-TR-01, OE-TR-02}
{OE-TR-01, TR-02}
{OE-TR-02, TR-01}
{TR-01, TR-02}

Order 3 (300)

{CB-315-111, CB-315-112, CB-735-12}
{CB-315-111, CB-315-112, CT-735-12}
{CB-315-111, CB-315-112, DS-735-12A}
{CB-315-111, CB-315-112, DS-735-12B}
{CB-315-111, CB-315-112, OE-TR-02}
{CB-315-111, CB-315-112, TR-02}
{CB-315-111, CB-735-12, CT-315-112}
{CB-315-111, CB-735-12, DS-315-112A}
{CB-315-111, CB-735-12, DS-315-112B}
{CB-315-111, CB-735-12, OE-315-112}
{CB-315-111, CT-315-112, CT-735-12}
{CB-315-111, CT-315-112, DS-735-12A}
{CB-315-111, CT-315-112, DS-735-12B}
{CB-315-111, CT-315-112, OE-TR-02}
{CB-315-111, CT-315-112, TR-02}
{CB-315-111, CT-735-12, DS-315-112A}
{CB-315-111, CT-735-12, DS-315-112B}
{CB-315-111, CT-735-12, OE-315-112}
{CB-315-111, DS-315-112A, DS-735-12A}
{CB-315-111, DS-315-112A, DS-735-12B}
{CB-315-111, DS-315-112A, OE-TR-02}
{CB-315-111, DS-315-112A, TR-02}
{CB-315-111, DS-315-112B, DS-735-12A}
{CB-315-111, DS-315-112B, DS-735-12B}
{CB-315-111, DS-315-112B, OE-TR-02}
{CB-315-111, DS-315-112B, TR-02}
{CB-315-111, DS-735-12A, OE-315-112}
{CB-315-111, DS-735-12B, OE-315-112}
{CB-315-111, OE-315-112, OE-TR-02}
{CB-315-111, OE-315-112, TR-02}
{CB-315-112, CB-735-12, CT-315-111}
{CB-315-112, CB-735-12, DS-315-111A}
{CB-315-112, CB-735-12, DS-315-111B}
{CB-315-112, CB-735-12, OE-315-111}
{CB-315-112, CT-315-111, CT-735-12}
{CB-315-112, CT-315-111, DS-735-12A}
{CB-315-112, CT-315-111, DS-735-12B}
{CB-315-112, CT-315-111, OE-TR-02}
{CB-315-112, CT-315-111, TR-02}
{CB-315-112, CT-735-12, DS-315-111A}
{CB-315-112, CT-735-12, DS-315-111B}
{CB-315-112, CT-735-12, OE-315-111}
{CB-315-112, DS-315-111A, DS-735-12A}
{CB-315-112, DS-315-111A, DS-735-12B}
{CB-315-112, DS-315-111A, OE-TR-02}
{CB-315-112, DS-315-111A, TR-02}
{CB-315-112, DS-315-111B, DS-735-12A}
{CB-315-112, DS-315-111B, DS-735-12B}
{CB-315-112, DS-315-111B, OE-TR-02}
{CB-315-112, DS-315-111B, TR-02}
{CB-315-112, DS-735-12A, OE-315-111}
{CB-315-112, DS-735-12B, OE-315-111}
{CB-315-112, OE-315-111, OE-TR-02}
{CB-315-112, OE-315-111, TR-02}
{CB-315-121, CB-315-122, CB-735-11}
{CB-315-121, CB-315-122, CT-735-11}
{CB-315-121, CB-315-122, DS-735-11A}
{CB-315-121, CB-315-122, DS-735-11B}
{CB-315-121, CB-315-122, OE-TR-01}
{CB-315-121, CB-315-122, TR-01}
{CB-315-121, CB-735-11, CT-315-122}
{CB-315-121, CB-735-11, DS-315-122A}
{CB-315-121, CB-735-11, DS-315-122B}
{CB-315-121, CB-735-11, OE-315-122}
{CB-315-121, CT-315-122, CT-735-11}
{CB-315-121, CT-315-122, DS-735-11A}
{CB-315-121, CT-315-122, DS-735-11B}
{CB-315-121, CT-315-122, OE-TR-01}
{CB-315-121, CT-315-122, TR-01}
{CB-315-121, CT-735-11, DS-315-122A}
{CB-315-121, CT-735-11, DS-315-122B}
{CB-315-121, CT-735-11, OE-315-122}
{CB-315-121, DS-315-122A, DS-735-11A}
{CB-315-121, DS-315-122A, DS-735-11B}
{CB-315-121, DS-315-122A, OE-TR-01}
{CB-315-121, DS-315-122A, TR-01}
{CB-315-121, DS-315-122B, DS-735-11A}
{CB-315-121, DS-315-122B, DS-735-11B}
{CB-315-121, DS-315-122B, OE-TR-01}
{CB-315-121, DS-315-122B, TR-01}
{CB-315-121, DS-735-11A, OE-315-122}
{CB-315-121, DS-735-11B, OE-315-122}
{CB-315-121, OE-315-122, OE-TR-01}
{CB-315-121, OE-315-122, TR-01}
{CB-315-122, CB-735-11, CT-315-121}
{CB-315-122, CB-735-11, DS-315-121A}
{CB-315-122, CB-735-11, DS-315-121B}
{CB-315-122, CB-735-11, OE-315-121}
{CB-315-122, CT-315-121, CT-735-11}
{CB-315-122, CT-315-121, DS-735-11A}
{CB-315-122, CT-315-121, DS-735-11B}
{CB-315-122, CT-315-121, OE-TR-01}
{CB-315-122, CT-315-121, TR-01}
{CB-315-122, CT-735-11, DS-315-121A}
{CB-315-122, CT-735-11, DS-315-121B}
{CB-315-122, CT-735-11, OE-315-121}
{CB-315-122, DS-315-121A, DS-735-11A}
{CB-315-122, DS-315-121A, DS-735-11B}
{CB-315-122, DS-315-121A, OE-TR-01}
{CB-315-122, DS-315-121A, TR-01}
{CB-315-122, DS-315-121B, DS-735-11A}
{CB-315-122, DS-315-121B, DS-735-11B}
{CB-315-122, DS-315-121B, OE-TR-01}
{CB-315-122, DS-315-121B, TR-01}
{CB-315-122, DS-735-11A, OE-315-121}
{CB-315-122, DS-735-11B, OE-315-121}
{CB-315-122, OE-315-121, OE-TR-01}
{CB-315-122, OE-315-121, TR-01}
{CB-735-11, CT-315-121, CT-315-122}
{CB-735-11, CT-315-121, DS-315-122A}
{CB-735-11, CT-315-121, DS-315-122B}
{CB-735-11, CT-315-121, OE-315-122}
{CB-735-11, CT-315-122, DS-315-121A}
{CB-735-11, CT-315-122, DS-315-121B}
{CB-735-11, CT-315-122, OE-315-121}
{CB-735-11, DS-315-121A, DS-315-122A}
{CB-735-11, DS-315-121A, DS-315-122B}
{CB-735-11, DS-315-121A, OE-315-122}
{CB-735-11, DS-315-121B, DS-315-122A}
{CB-735-11, DS-315-121B, DS-315-122B}
{CB-735-11, DS-315-121B, OE-315-122}
{CB-735-11, DS-315-122A, OE-315-121}
{CB-735-11, DS-315-122B, OE-315-121}
{CB-735-11, OE-315-121, OE-315-122}
{CB-735-12, CT-315-111, CT-315-112}
{CB-735-12, CT-315-111, DS-315-112A}
{CB-735-12, CT-315-111, DS-315-112B}
{CB-735-12, CT-315-111, OE-315-112}
{CB-735-12, CT-315-112, DS-315-111A}
{CB-735-12, CT-315-112, DS-315-111B}
{CB-735-12, CT-315-112, OE-315-111}
{CB-735-12, DS-315-111A, DS-315-112A}
{CB-735-12, DS-315-111A, DS-315-112B}
{CB-735-12, DS-315-111A, OE-315-112}
{CB-735-12, DS-315-111B, DS-315-112A}
{CB-735-12, DS-315-111B, DS-315-112B}
{CB-735-12, DS-315-111B, OE-315-112}
{CB-735-12, DS-315-112A, OE-315-111}
{CB-735-12, DS-315-112B, OE-315-111}
{CB-735-12, OE-315-111, OE-315-112}
{CT-315-111, CT-315-112, CT-735-12}
{CT-315-111, CT-315-112, DS-735-12A}
{CT-315-111, CT-315-112, DS-735-12B}
{CT-315-111, CT-315-112, OE-TR-02}
{CT-315-111, CT-315-112, TR-02}
{CT-315-111, CT-735-12, DS-315-112A}
{CT-315-111, CT-735-12, DS-315-112B}
{CT-315-111, CT-735-12, OE-315-112}
{CT-315-111, DS-315-112A, DS-735-12A}
{CT-315-111, DS-315-112A, DS-735-12B}
{CT-315-111, DS-315-112A, OE-TR-02}
{CT-315-111, DS-315-112A, TR-02}
{CT-315-111, DS-315-112B, DS-735-12A}
{CT-315-111, DS-315-112B, DS-735-12B}
{CT-315-111, DS-315-112B, OE-TR-02}
{CT-315-111, DS-315-112B, TR-02}
{CT-315-111, DS-735-12A, OE-315-112}
{CT-315-111, DS-735-12B, OE-315-112}
{CT-315-111, OE-315-112, OE-TR-02}
{CT-315-111, OE-315-112, TR-02}
{CT-315-112, CT-735-12, DS-315-111A}
{CT-315-112, CT-735-12, DS-315-111B}
{CT-315-112, CT-735-12, OE-315-111}
{CT-315-112, DS-315-111A, DS-735-12A}
{CT-315-112, DS-315-111A, DS-735-12B}
{CT-315-112, DS-315-111A, OE-TR-02}
{CT-315-112, DS-315-111A, TR-02}
{CT-315-112, DS-315-111B, DS-735-12A}
{CT-315-112, DS-315-111B, DS-735-12B}
{CT-315-112, DS-315-111B, OE-TR-02}
{CT-315-112, DS-315-111B, TR-02}
{CT-315-112, DS-735-12A, OE-315-111}
{CT-315-112, DS-735-12B, OE-315-111}
{CT-315-112, OE-315-111, OE-TR-02}
{CT-315-112, OE-315-111, TR-02}
{CT-315-121, CT-315-122, CT-735-11}
{CT-315-121, CT-315-122, DS-735-11A}
{CT-315-121, CT-315-122, DS-735-11B}
{CT-315-121, CT-315-122, OE-TR-01}
{CT-315-121, CT-315-122, TR-01}
{CT-315-121, CT-735-11, DS-315-122A}
{CT-315-121, CT-735-11, DS-315-122B}
{CT-315-121, CT-735-11, OE-315-122}
{CT-315-121, DS-315-122A, DS-735-11A}
{CT-315-121, DS-315-122A, DS-735-11B}
{CT-315-121, DS-315-122A, OE-TR-01}
{CT-315-121, DS-315-122A, TR-01}
{CT-315-121, DS-315-122B, DS-735-11A}
{CT-315-121, DS-315-122B, DS-735-11B}
{CT-315-121, DS-315-122B, OE-TR-01}
{CT-315-121, DS-315-122B, TR-01}
{CT-315-121, DS-735-11A, OE-315-122}
{CT-315-121, DS-735-11B, OE-315-122}
{CT-315-121, OE-315-122, OE-TR-01}
{CT-315-121, OE-315-122, TR-01}
{CT-315-122, CT-735-11, DS-315-121A}
{CT-315-122, CT-735-11, DS-315-121B}
{CT-315-122, CT-735-11, OE-315-121}
{CT-315-122, DS-315-121A, DS-735-11A}
{CT-315-122, DS-315-121A, DS-735-11B}
{CT-315-122, DS-315-121A, OE-TR-01}
{CT-315-122, DS-315-121A, TR-01}
{CT-315-122, DS-315-121B, DS-735-11A}
{CT-315-122, DS-315-121B, DS-735-11B}
{CT-315-122, DS-315-121B, OE-TR-01}
{CT-315-122, DS-315-121B, TR-01}
{CT-315-122, DS-735-11A, OE-315-121}
{CT-315-122, DS-735-11B, OE-315-121}
{CT-315-122, OE-315-121, OE-TR-01}
{CT-315-122, OE-315-121, TR-01}
{CT-735-11, DS-315-121A, DS-315-122A}
{CT-735-11, DS-315-121A, DS-315-122B}
{CT-735-11, DS-315-121A, OE-315-122}
{CT-735-11, DS-315-121B, DS-315-122A}
{CT-735-11, DS-315-121B, DS-315-122B}
{CT-735-11, DS-315-121B, OE-315-122}
{CT-735-11, DS-315-122A, OE-315-121}
{CT-735-11, DS-315-122B, OE-315-121}
{CT-735-11, OE-315-121, OE-315-122}
{CT-735-12, DS-315-111A, DS-315-112A}
{CT-735-12, DS-315-111A, DS-315-112B}
{CT-735-12, DS-315-111A, OE-315-112}
{CT-735-12, DS-315-111B, DS-315-112A}
{CT-735-12, DS-315-111B, DS-315-112B}
{CT-735-12, DS-315-111B, OE-315-112}
{CT-735-12, DS-315-112A, OE-315-111}
{CT-735-12, DS-315-112B, OE-315-111}
{CT-735-12, OE-315-111, OE-315-112}
{DS-315-111A, DS-315-112A, DS-735-12A}
{DS-315-111A, DS-315-112A, DS-735-12B}
{DS-315-111A, DS-315-112A, OE-TR-02}
{DS-315-111A, DS-315-112A, TR-02}
{DS-315-111A, DS-315-112B, DS-735-12A}
{DS-315-111A, DS-315-112B, DS-735-12B}
{DS-315-111A, DS-315-112B, OE-TR-02}
{DS-315-111A, DS-315-112B, TR-02}
{DS-315-111A, DS-735-12A, OE-315-112}
{DS-315-111A, DS-735-12B, OE-315-112}
{DS-315-111A, OE-315-112, OE-TR-02}
{DS-315-111A, OE-315-112, TR-02}
{DS-315-111B, DS-315-112A, DS-735-12A}
{DS-315-111B, DS-315-112A, DS-735-12B}
{DS-315-111B, DS-315-112A, OE-TR-02}
{DS-315-111B, DS-315-112A, TR-02}
{DS-315-111B, DS-315-112B, DS-735-12A}
{DS-315-111B, DS-315-112B, DS-735-12B}
{DS-315-111B, DS-315-112B, OE-TR-02}
{DS-315-111B, DS-315-112B, TR-02}
{DS-315-111B, DS-735-12A, OE-315-112}
{DS-315-111B, DS-735-12B, OE-315-112}
{DS-315-111B, OE-315-112, OE-TR-02}
{DS-315-111B, OE-315-112, TR-02}
{DS-315-112A, DS-735-12A, OE-315-111}
{DS-315-112A, DS-735-12B, OE-315-111}
{DS-315-112A, OE-315-111, OE-TR-02}
{DS-315-112A, OE-315-111, TR-02}
{DS-315-112B, DS-735-12A, OE-315-111}
{DS-315-112B, DS-735-12B, OE-315-111}
{DS-315-112B, OE-315-111, OE-TR-02}
{DS-315-112B, OE-315-111, TR-02}
{DS-315-121A, DS-315-122A, DS-735-11A}
{DS-315-121A, DS-315-122A, DS-735-11B}
{DS-315-121A, DS-315-122A, OE-TR-01}
{DS-315-121A, DS-315-122A, TR-01}
{DS-315-121A, DS-315-122B, DS-735-11A}
{DS-315-121A, DS-315-122B, DS-735-11B}
{DS-315-121A, DS-315-122B, OE-TR-01}
{DS-315-121A, DS-315-122B, TR-01}
{DS-315-121A, DS-735-11A, OE-315-122}
{DS-315-121A, DS-735-11B, OE-315-122}
{DS-315-121A, OE-315-122, OE-TR-01}
{DS-315-121A, OE-315-122, TR-01}
{DS-315-121B, DS-315-122A, DS-735-11A}
{DS-315-121B, DS-315-122A, DS-735-11B}
{DS-315-121B, DS-315-122A, OE-TR-01}
{DS-315-121B, DS-315-122A, TR-01}
{DS-315-121B, DS-315-122B, DS-735-11A}
{DS-315-121B, DS-315-122B, DS-735-11B}
{DS-315-121B, DS-315-122B, OE-TR-01}
{DS-315-121B, DS-315-122B, TR-01}
{DS-315-121B, DS-735-11A, OE-315-122}
{DS-315-121B, DS-735-11B, OE-315-122}
{DS-315-121B, OE-315-122, OE-TR-01}
{DS-315-121B, OE-315-122, TR-01}
{DS-315-122A, DS-735-11A, OE-315-121}
{DS-315-122A, DS-735-11B, OE-315-121}
{DS-315-122A, OE-315-121, OE-TR-01}
{DS-315-122A, OE-315-121, TR-01}
{DS-315-122B, DS-735-11A, OE-315-121}
{DS-315-122B, DS-735-11B, OE-315-121}
{DS-315-122B, OE-315-121, OE-TR-01}
{DS-315-122B, OE-315-121, TR-01}
{DS-735-11A, OE-315-121, OE-315-122}
{DS-735-11B, OE-315-121, OE-315-122}
{DS-735-12A, OE-315-111, OE-315-112}
{DS-735-12B, OE-315-111, OE-315-112}
{OE-315-111, OE-315-112, OE-TR-02}
{OE-315-111, OE-315-112, TR-02}
{OE-315-121, OE-315-122, OE-TR-01}
{OE-315-121, OE-315-122, TR-01}

Gaps

315kV-NETWORK (sink) The spec doesn't set the sink. I used a virtual node fed from both 315 kV buses, so supply to either bus counts as success. If the study needs a particular bus (or both buses) supplied, the cut sets will change.
OE-* operating-error blocks The drawing doesn't show operating-error blocks. Following the spec, I put one in series in each transformer path (OE-TR-01/02) and one in each 315 kV branch (OE-315-111/112/121/122). Each is independent, and their exact place in the series chain doesn't affect the cut sets.

Assumptions

Scope: Everything inside the dashed boundary: BUS 735, two 735 kV transformer bays (DS/CB/CT/DS + TR), four 315 kV bays, BUS 315-A and BUS 315-B, plus the operating-error blocks.. Spec says the scope is the dashed study boundary.

Boundary: Source = 735 kV lines arriving at BUS 735. Sink = a single virtual node for the 315 kV network, fed from both BUS 315-A and BUS 315-B.. The drawing marks the 735 kV lines as the source and both 315 kV buses as outgoing to the 315 kV network. Under any-path success, supply reaching either 315 kV bus counts.

Can fail: breaker, disconnector, ct, transformer, other. Spec: breakers, disconnectors, CTs and power transformers can fail; 'other' holds the operating-error blocks the spec requires. Busbars, source and sink are perfect connectors.

Success: any_path. Spec: any one source-to-sink path is enough.

Not modelled:

735 kV lines and the 315 kV network beyond the buses: They are outside the dashed study boundary.
Protection, control, auxiliary systems, capacity limits (N-1 loading): Note 4 says they are not shown; the any-path rule ignores capacity.
Common-mode and maintenance outages: The spec doesn't ask for them.

r_20261029_190447_1fc8

Review

1 · Power reaches the load by these paths

2 · Parts not on the drawing

3 · Assumptions

Summary

Single points of failure

Pairs

Drawing and graph

Not on the drawing

Block diagram

Cut sets

Reference: none

This model

Gaps

Assumptions