A set of Excel programs that transform your existing Standard Operating Procedures into a structured, ISA‑106-compliant format — converting written operational knowledge into pseudo-code, Steps, Transitions, and Step Actions ready for FRS development.
P4 is the critical bridge between your written operational knowledge and formal control system design. It captures the intent locked inside existing SOPs and restructures it into an engineering artefact that can flow directly into P5 URS and P6 FRS — and ultimately into ACM-generated DCS code.
Every process plant has a library of Standard Operating Procedures. Written over years by operators and engineers, these documents contain an enormous amount of operational knowledge — the steps, decisions, conditions, and actions that define how the plant actually runs.
The problem is that this knowledge exists as unstructured prose. You cannot directly convert a written SOP into URS requirements, FRS logic, or DCS code. P4 bridges this gap systematically — extracting and restructuring the intent of the SOP into a form that the rest of the CDL pipeline can consume.
/* Startup Procedure — Reactor Feed Section */
"Ensure all isolation valves on
the feed line are in the closed
position before opening the
feed pump suction valve. Start
the feed pump only after
confirming suction pressure
above 2.5 bar. Slowly ramp feed
rate to 50% over 10 minutes..."
STEP S03: Feed System Preparation PRE-CONDITION: FV-101 = CLOSED FV-102 = CLOSED FV-103 = CLOSED ACTION: OPEN XV-100 (Feed Pump Suction) WAIT PI-100 > 2.5 bar TRANSITION to S04: PI-100 > 2.5 bar AND XV-100 = OPEN_CONFIRMED STEP S04: Feed Pump Start & Ramp ACTION: START P-100 (Feed Pump) RAMP FIC-100.SP 0 → 50% / 10min
P4 processes the SOP through four sequential Excel-based stages. Each stage transforms the content into a progressively more structured form — from narrative to pseudo-code to formal step logic to exportable XML.
The raw SOP text is processed through the P4 Excel tool, which guides the engineer through identifying and tagging each procedural element — conditions, actions, hold points, and transitions — converting them into CDL p-Code syntax.
The p-Code is analysed to identify natural step boundaries — the points where one discrete operational state ends and another begins. For each step, the entry conditions (transitions) are formalised.
Each p-Code block is converted into a set of discrete Step Actions — the specific control operations the DCS must execute when the step is active. Actions are categorised by type: device commands, setpoint changes, ramp sequences, and wait conditions.
The completed Step Actions structure is exported to Industrial IT XML format. This machine-readable export can be imported directly into compatible DCS engineering environments and provides the structured input for the Step‑CCM Matrix in P6 FRS.
The final P4 output is a structured XML file that encodes the full step logic in Industrial IT format. This is not a documentation artefact — it is an engineering data file that is imported directly into FRS development and compatible DCS engineering tools.
Every step, transition condition, action, and pre-condition from the p-Code is preserved in the XML — maintaining a complete traceable link from the original SOP narrative to the deployed DCS code.
<!-- P4 Industrial IT XML Export --> <!-- Unit: Reactor UM / Startup --> <Procedure id="REACT-SU" um="Reactor" mode="Startup"> <Step id="S03" name="Feed System Preparation"> <PreConditions> <Condition tag="FV-101" state="CLOSED"/> <Condition tag="PI-100" op="GT" value="2.5"/> </PreConditions> <Actions> <Action type="OPEN" device="XV-100"/> <Action type="WAIT" tag="PI-100" op="GT" value="2.5"/> </Actions> <Transition to="S04"> <Condition tag="PI-100" op="GT" value="2.5"/> </Transition> </Step> </Procedure>
P4 sits at the junction between the assessment/classification phases (P1–P3) and the requirements design phases (P5–P6). It is the last tool that works primarily from existing plant documents — and the first to produce structured engineering artefacts that flow into formal design.
The p-Code and Step Actions outputs from P4 are consumed in two places in the CDL pipeline: the A3‑SOP section of the P5 URS Builder, and the A3‑SOP + C2/C4 Steps sections of the P6 FRS Engine.
SOPs encode years of hard-won operational experience. P4 extracts and preserves this knowledge in a structured form that survives staff turnover and automation projects.
Every step in the FRS and every line of ACM-generated code can be traced back to a specific section of the original SOP — essential for regulated environments.
Without P4, engineers in P5 and P6 must re-interpret raw SOP text independently — introducing inconsistencies. P4 creates a single agreed source of truth.
The more complete and accurate the p-Code import in P6 FRS, the more complete and accurate the DCS code generated by P7 ACM. P4 quality directly impacts final output quality.
P4 is available through our online store or directly by invoice. A managed service engagement is also available — we work through your SOP library with your engineering team to produce the p-Code and Step Actions outputs together.
A comprehensive walkthrough of the full P4 SOP Converter package is available by Zoom. Contact us at info@CtrlDesigner.com with your company email to request a session.