RMU Interlock Evidence Pack: What to Review Before Factory Witnessing

Before an RMU factory witness, the EPC should align the interlock matrix, controlled schematics, applicable procedure, equipment identity, witness points, responsible signatories, and deviation route in one evidence index. This is a document-readiness guide, not an operating instruction or test result.

Part 1. Define the interlock evidence boundary

An RMU interlock can involve a key, mechanical movement, electrical permissive, access boundary, or a project-specific sequence. Start by naming the equipment scope and the evidence expected for the witness. A product photograph or generic switchgear description does not prove an interlock design.

Important: The witness package should identify the controlled configuration and the approved procedure before anyone interprets a record as evidence of acceptance. (IEC 62271-202)

Part 2. Align identity and revision records

Every record should connect to the RMU panel, functional unit, drawing revision, and applicable project package. Keep the equipment identity and document revision visible in the index.

Part 3. Map the matrix, schematic and procedure

The interlock matrix should point to the schematic or drawing evidence and the procedure step where the witness occurs. This mapping keeps the review factual and exposes missing links before the witness date.

For a related protection-boundary topic, see RMU load-break switch versus circuit breaker. It does not establish an interlock result.

Part 4. Assign witness and approval responsibility

List who prepares the matrix, who controls drawings, who witnesses the procedure, who reviews technical evidence, and who accepts a deviation. A signature on an attendance sheet should not silently transfer those responsibilities.

The responsibility matrix should identify:

1. the supplier contact for drawings and procedure;
2. the EPC or owner witness;
3. the document controller for the evidence index;
4. the technical reviewer for open questions; and
5. the authority allowed to accept a deviation.

Part 5. Record deviations and configuration changes

Give every discrepancy a unique reference and record the affected panel, document, factual observation, owner, due date, and disposition route. Keep an open action separate from a revised drawing or a closed record.

The RMU internal arc classification article is a related site-design topic, not an interlock test method.

Part 6. Build the RMU interlock evidence RFQ pack

Send one controlled revision register with the quotation or FAT request. Ask the supplier to identify missing inputs and deviations instead of silently applying defaults.

Part 7. Use the controlled pack for a product enquiry

After the evidence index, scope matrix and open actions are controlled, the EPC can discuss the equipment scope with the JUBANG switchgear and ring main unit range.

The product-family page does not prove an interlock design, operation, certification, compliance, or project acceptance. Use JUBANG Contact Us to submit the controlled scope for project-specific review.

FAQs

What documents show switchgear interlocks?

Use the controlled interlock matrix, schematic or wiring reference, applicable procedure, equipment identity, witness record and revision index.

How are RMU interlocks tested?

The approved project procedure defines the checks. This article explains how to organize its evidence and does not publish test values or results.

Who approves an interlock change?

The project responsibility and change-control plan should name the technical reviewer and the authority allowed to accept the change.

What should be checked before a FAT witness?

Check the equipment identity, current drawings, matrix, procedure, witness points, signatories, calibration records and deviation route.

Can a schematic revision prove an interlock works?

No. A revision establishes document context; operation evidence requires the approved project procedure and witnessed record.

What should an EPC send with an RMU interlock evidence RFQ?

Send the scope basis, panel identities, matrix, drawings, procedure, ITP, quality-record requirements and action-control template.

References

• Project scope source for interlock review: IEC 62271-202 source page
• Industry source for interlock evidence: CIGRE technical knowledge community