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How to specify a Distribution Board

What to put on an RFQ for Distribution Board: the ratings, documents, and constraints that change the quote.

25 Oct 2026 · 3 min read · Tradinor Desk

Specification points for Distribution BoardTRADINOR · FIGUREWhat to lock for Distribution BoardCoordinationRated currentBreaking capacityPoles and trip
Put these on the RFQ for Distribution Board before you compare prices.

A buyer searching for Distribution Board is usually trying to stop a bad substitute. Low-voltage distribution gear is specified by the fault level, the current, the poles, and the enclosure it sits in. The notes below are selection criteria for a Distribution Board. They are not a catalog promise. Confirm every rating on the current datasheet, drawing, or test report for the revision you will receive.

What has to be true of Distribution Board

Low-voltage distribution gear is specified by the fault level, the current, the poles, and the enclosure it sits in. For a Distribution Board, start from the duty, then the interface to the rest of the machine or the room, then the document that proves the claim. A lower price that leaves one of those blank is a different product.

Distribution Board is easy to confuse with Bus Duct. If the quote could be read as either, add the line that separates them: the rating, the fitment, or the standard named below. Link the drawing number to that line so receiving inspection can reject the wrong one.

Numbers that change the quote

Line What to write for Distribution Board
Coordination What sits upstream and downstream so the combination is selective.
Rated current Continuous current at the ambient inside the panel.
Breaking capacity The fault current the device must interrupt, in kiloamperes.
Poles and trip Poles, curve or trip unit, and residual current if people are protected.
Voltage and frequency The real mains, single or three phase.
Mounting DIN rail, panel, or a stated enclosure with its IP code.

How to compare two offers

Lay both quotes for Distribution Board on one sheet and line up coordination, rated current, and breaking capacity. If a cell is empty, the offer is not finished. Ask for the missing line in writing. When those match, the honest difference is lead time, the test evidence, and who carries the warranty. Do not average a fully specified Distribution Board with a cheaper line that omitted coordination.

Documents worth having before the deposit

IEC 60947 is the usual family for low-voltage switchgear. Ask which part of it the declaration uses. The file should name Distribution Board and the revision, not only the supplier’s homepage. A factory quality certificate such as ISO 9001 can sit beside that file. It does not replace it.

Failures that show up after delivery

  • Cutting an enclosure and assuming the IP code survived.
  • Sizing a breaker from the load current and ignoring the fault level.
  • Mixing a person-protection device with a plain miniature breaker.

On a Distribution Board, the expensive version of the first mistake is discovering it after the goods are in the crate. Put the rejection condition in the purchase order while the supplier can still restate the offer.

A worked RFQ line

Use this shape, then replace the brackets with your duty: “Distribution Board — Write current, breaking capacity, poles, voltage, and the enclosure code.” That sentence is a template, not a rating of any brand. If a supplier’s datasheet uses different units, convert them onto this sheet so the next offer can be compared.

Where words like outdoor belong

Searches often add a constraint to Distribution Board: outdoor, or OEM / custom. Keep those on this page. Outdoor means UV, temperature cycle, and corrosion, not only a gasket. Name the climate and the years the gasket is expected to last. OEM or custom means a drawing, a revision, and a statement of who owns the tool. Without those, you are buying the catalog part. If you need a third constraint, add it as another line on the same drawing. A second URL that only swaps the adjective does not give a buyer a second fact.

Related in this section: how to specify Bus Duct.

Questions buyers actually ask

What should an RFQ for Distribution Board include?

Write current, breaking capacity, poles, voltage, and the enclosure code.

Is a cheaper Distribution Board the same part?

Only if coordination, rated current, and the documents match. A missing line is a different offer.

Do waterproof, OEM, or IP words need their own page?

No. For Distribution Board they are extra lines on this specification. Ask for the test or the drawing that gives the word a value.