How to Control Drawing Revisions Before a Prefabricated Substation RFQ

Before a prefabricated-substation RFQ is issued, the project team should identify one current source for every drawing and record who may change or approve it. A controlled register prevents an old one-line diagram, civil sketch, or supplier markup from being treated as a silent instruction.

This is a document-control guide, not a drawing package or an engineering approval. It does not set dimensions, cable routes, equipment ratings, safety arrangements, or construction instructions.

Part 1. Define the controlled drawing boundary

A project may call many files “the drawing”: a one-line, a general arrangement, a civil-interface sketch, a supplier outline, or a marked PDF. Begin by naming the file type, revision, source, date, and intended decision. A file without those fields is reference material, not a controlled instruction.

IEC 62271-202 is useful scope context for AC prefabricated substations. It does not issue a project drawing or approve a configuration.

Important: Do not use an untracked markup as an RFQ instruction. Put its source, revision, owner, and acceptance route in the register before relying on it. (IEC 62271-202)

Part 2. Build one register for project records

Use one register rather than separate email chains. It should link each record to its source and decision purpose, while allowing the project team to show what is still missing.

The register does not turn an early document into a final design. It shows which party must provide the next controlled input.

Part 3. Separate document owners from approvers

The party that supplies a drawing is not automatically the party that accepts a change. Make both roles explicit. A supplier may issue a marked document, an EPC may coordinate interfaces, and an owner or design authority may accept a revision under the project process.

For the electrical-content review of a one-line, see the related prefabricated substation single-line diagram article. This article controls revision ownership rather than interpreting the electrical design.

Part 4. Record supplier markups and deviations

Every markup should reference the controlled file it comments on. Give it a date, issuing party, question, affected interface, and an acceptance path. Keep a supplier’s clarification separate from a project-approved change.

Useful questions include:

1. Which revision is being marked?
2. Does the markup request information, identify a deviation, or propose a change?
3. Which party must respond?
4. Which controlled record will be updated if the issue is accepted?
5. Who confirms that the old instruction is no longer to be used?

This method makes the record traceable without deciding whether a specific technical proposal is suitable.

Part 5. Issue a controlled review package

Before a review meeting or RFQ release, freeze a document list for that purpose. The package should show the issue date, the documents included, excluded items, unresolved actions, and the person responsible for the next update.

Do not treat a frozen RFQ package as a construction release or an acceptance record.

Part 6. Attach the drawing register to the RFQ

Ask bidders to use the controlled register and identify any missing input or deviation. A concise RFQ table can prevent suppliers from filling gaps with unrelated catalogue assumptions.

The project authority must confirm all technical choices and project requirements outside this record-control process.

Part 7. Move from records to a product enquiry

After the project controls its drawing register, it can review the JUBANG prefabricated substation range as an equipment-family starting point.

The page cannot replace project drawings, approve a revision, establish equipment fit, or demonstrate compliance. Use JUBANG Contact Us to submit the register and identify the project documents available for review.

FAQs

Is this an approved drawing process?

No. It is a practical register structure. The contract, project procedures, and responsible approval authority determine the actual approval process.

Which documents belong in the register?

List every document used to define the RFQ or review boundary, including the current one-line, civil interfaces, supplier documents, owner requirements, and open actions.

Who can approve a revision?

The project should name the approval authority in its own process. A document owner or reviewer may not have authority to accept the change.

How should markups be recorded?

Link each markup to the controlled revision, issuing party, question, affected interface, response owner, and acceptance route.

What makes a drawing set controlled?

Each item has a source, revision, date, status, owner, intended use, and a clear route for resolving superseded or open items.

What should accompany an RFQ?

Attach the controlled drawing list, relevant interfaces, open-action log, requested deliverables, and the commercial scope statement.

Can a product page replace project drawings?

No. A product page can introduce a range but cannot define project interfaces, approve a revision, or confirm a configuration.

References

• IEC source page on prefabricated substations
• CIGRE technical knowledge community