Type-tested or verified: what AS/NZS 61439 means in a switchboard tender
A switchboard specification that asks for a type-tested board is using the language of AS/NZS 3439, the standard AS/NZS 61439 replaced. Under 61439 a board is proven in two steps. Design verification proves the assembly system once, by test, by calculation or by comparison with a tested reference design, and the original manufacturer holds the record. Each board built from that system then gets its own routine verification, which the switchboard builder carries out before it leaves the workshop. The tender question is which of those records you can return, against the edition the specification cites.
Reading the switchboard specification and listing every 61439 requirement with its clause, beside the evidence the returnable asks for, is work Elora Grid does. Whether a design is verified for the ratings you are offering stays with your engineers.
What replaced type-tested and partially type-tested?
Design verification. AS/NZS 3439 sorted boards into type-tested and partially type-tested assemblies, and a certificate for one board was often waved through for another that looked similar. AS/NZS 61439.2 lists the design characteristics every assembly has to satisfy, among them strength of materials, degree of protection, clearances and creepage, temperature rise, short-circuit withstand and mechanical operation, and allows each one to be verified by the method that suits it.
So the useful evidence is narrower than a certificate. It is the verification record for the system you are building from, covering the current, the short-circuit rating and the arrangement you are actually offering.
Who is responsible for what?
The original manufacturer designs and verifies the assembly system: the enclosure, the busbar system and the arrangements it has tested or assessed. The assembly manufacturer, usually the switchboard builder, designs the specific board from the user's requirements and the original manufacturer's instructions, builds it, and does the routine verification.
The line moves when the builder departs from those instructions. Extend a busbar run past the tested arrangement, or fit a device the system was never verified with, and the builder takes on the original manufacturer's role for that change, including its design verification. A quote priced on the system supplier's records quietly assumes nothing like that will happen.
What does the specification have to tell you?
The ratings and conditions the board is built to. That means the rated voltage, the rated current of the board and of each circuit, the short-time withstand current and its duration, such as 50 kA for one second, the degree of protection, the form of separation, the installation conditions and whether arc fault containment is required. The standard carries a template for exactly this information, and a good specification fills it in.
Most do not, completely. A missing short-time rating or ambient temperature is a clarification to send during the question period, and if the answer never comes, the value you assumed goes in your qualifications.
Form of separation and arc fault: where the price moves
The form of separation runs from Form 1, with no internal separation, to Form 4b, where busbars, functional units and terminals are all separated from each other. Australian specifications often write it with suffixes, such as 3bih or 4bih, describing how the separation is achieved. Two boards with the same single line diagram can differ more in price on the form than on anything else.
Arc fault is the other line to read slowly. The Wiring Rules, AS/NZS 3000, set arcing fault requirements for switchboards rated 800 A or more, which can be met by internal separation or by protection that clears the fault fast enough. Arc fault containment testing, to Annex ZD of AS/NZS 61439.2 or to IEC TR 61641, is a separate and optional requirement that utility, mining and data centre specifications often call up. Where the specification asks for it, check the test current and duration it names, and whether the system's test report covers the arrangement you are offering.
Which edition does the specification cite?
AS/NZS 61439.1 and AS/NZS 61439.2 were republished in February 2026 as second editions, based on the 2020 editions of IEC 61439-1 and IEC 61439-2. Specifications written before then cite the 2016 editions, and many will keep doing so for a while.
If the edition is not stated, or the specification cites 2016 while the system supplier's records are to the new edition, ask which governs. Otherwise state the edition you have priced to in the qualifications, so the evidence you return and the edition the client expects match.
The evidence a switchboard tender usually asks for
| Requirement | Evidence to return | Who holds it |
|---|---|---|
| Design verification | Verification records for the assembly system at the ratings offered | Original manufacturer |
| Routine verification | A routine verification report for each board, before dispatch | Assembly manufacturer |
| Short-time withstand | The record showing the rated current for the specified duration | Original manufacturer |
| Form of separation | A statement of the form, with the GA showing the compartments | Assembly manufacturer |
| Arc fault containment, if specified | A test report to Annex ZD or IEC TR 61641 for the arrangement offered | Original manufacturer |
- 01Find every 61439 line. Search the specification, the datasheets and the returnables for 61439, 3439, type-tested and form, and list each with its clause.
- 02Fill the ratings. Record voltage, currents, short-time withstand and duration, IP rating, form and ambient, and mark each one the specification leaves blank.
- 03Match the evidence. For each requirement, name the record that proves it and who holds it, original manufacturer or builder.
- 04Check the edition. Note which edition of 61439 the specification cites and which edition the records are to.
- 05Qualify what is left. Send the blanks as clarifications, and put any unanswered value in the qualifications.
Common questions
Is type-tested still a valid requirement?
The words come from AS/NZS 3439, which 61439 replaced, so a board can no longer be type-tested in the old sense. Read the requirement as a request for design verification under 61439, say so in your clarifications, and return the original manufacturer's verification records.
Who does design verification for a custom switchboard?
The original manufacturer verifies the assembly system it supplies. The switchboard builder carries out routine verification on each board, and takes on design verification for any part of the board that departs from the system's instructions, such as a busbar arrangement or a device the system was never verified with.
Is arc fault containment mandatory under AS/NZS 61439?
No. Containment testing to Annex ZD or IEC TR 61641 is optional under the standard, although many utility, mining and data centre specifications require it. Separately, AS/NZS 3000 sets arcing fault requirements for switchboards rated 800 A or more, which can be met by internal separation or by protective devices, so read both the specification and the Wiring Rules clause it relies on.
Can Elora Grid check a switchboard specification against AS/NZS 61439?
It reads the specification, the datasheets and the returnable schedules and returns a compliance checklist of every 61439 requirement, rating and test, each cited to the clause it came from, with the blank ratings flagged as clarifications. Whether the system you are offering is verified for those ratings is your engineers' call.