مدقق شكل الفصل في لوحة التوزيع

How this is calculated#

The tool checks whether Clause 2.5.5 of AS/NZS 3000:2018 asks for separation inside a switchboard. It also reads the access and exit figures of Clause 2.10.2.2 and the Appendix K examples.

1. Scope. It compares the board rating with the Cl 2.5.5 threshold. At or above it, Cl 2.5.5 applies.
2. Incoming conductors. Where Cl 2.5.5 applies, the incoming supply conductors are insulated or separated (Cl 2.5.5.1).
3. Internal separation. The tool says if the Cl 2.5.5.2 route needs internal separation. It lists the forms that suit that route, from Paragraph K6.2 and Table K2.
4. Access. From Cl 2.10.2.2 it gives the clearance from each face that needs access. It also gives the unimpeded space around the board. A domestic board has its own front clearance.
5. Exits. A switchroom can pass the rating or length trigger. Then the tool gives the exit count and doorway size.
6. Clearance example. It reads the Appendix K clearance for the impulse voltage you pick (Paragraphs K6.4 and K6.5).

Worked example#

A 1000 A commercial board in a switchroom. Cl 2.5.5 applies and internal separation is required. Forms 3b, 4a or 4b suit. The tool gives 2 exit paths, set well apart. The Appendix K clearance at 6 kV is 5.5 mm.

Limits#

• Appendix K is informative. Its clearance and creepage figures are examples. Verify them to AS/NZS 61439.1.
• The tool holds the Cl 2.5.5.2 route only. Cl 2.5.5.1 offers other routes.
• Under the trigger, the tool gives no exit count and no doorway size.
• Measure each clearance with the doors and gear in the positions the clause names.
• Door swing and hold-open rules appear as warnings only.

See also: Industrial switchboards, Switchboard fault rating and busbar withstand and the fault rating calculator.