AS/NZS 3000:2018
Table 8.1, B4.5 multipliers
Maximum earth fault loop impedance multipliers by MCB curve
The loop impedance and cable size tools read the highest loop impedance a circuit may have for its device curve and rating. The measured or calculated Zs is compared with it.
Verified: read against the printed standard, pages 427, 449. Checked 27 Sept 2026.
Units: Multiplier ×In
These are the values AmpSize encodes. No text of the standard is reproduced. Verify against the current standard.
3 rows
| Curve | Multiplier (×In) |
|---|---|
| B | 4 |
| C | 7.5 |
| D | 12.5 |
Tools that read it (6)
Guides and learn pages that cite it (18)
- Lighting circuit loop impedance, B curve 10 A
- A test sheet for a house board
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- AmpSize vs jCalc vs free cable sizing tools
- AS/NZS 3000 Table 8.1: max Zs by curve and rating
- Earth fault loop impedance and maximum Zs
- Checking an existing circuit
- IEC 60364 and the Wiring Rules
- Loop impedance and disconnection time
- Testing to Section 8: what each test proves