WEBVTT

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Ground Truth, for owners and managers.

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What we found, and what it means.

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This system unloads hydrochloric acid
from tank trailers into a receiver, V110.

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Two pumps move it on to a destination tank.

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One small panel, CP-101, controls it.

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The only records were eleven
site photos and a program backup,

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with no comments at all.

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We rebuilt the logic and ran it.

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Watch the emergency stop.

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When it is pressed, the pump stops.

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When it is released, its permission to
run comes back by itself, with no reset.

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The stop acts only through the controller.

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Whether a pump then restarts on its
own depends on the starter wiring,

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an open question for the field walk.

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In all, we found fourteen
latent logic findings.

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Four are severity A, the most serious:

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a broken trip wire gives no
trip, the stop you just saw,

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a horn disabled in the field, and a
high-high level that does not stop the pumps.

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Each one comes with a recommended fix,

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ready for management of
change and the hazard review.

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Every statement is checked.

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The model runs the real program, with zero
mismatches, and every test case passes.

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You get a decision-ready findings list, a
defensible starting point for the upgrade,

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and a firm basis before
anyone changes the panel.

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Know what your control system
actually does, before you change it.