AS/NZS 3000:2018

B1

Maximum route lengths for conductor sizes and protective devices

The maximum circuit length tool reads the route length Table B1 allows for a conductor pair and a protective device, for a 0.4 s disconnection time at 230 V. A pair the table does not print has no tabulated length.

Verified: read against the printed standard, pages 452–453. Checked 26 Sept 2026.

Units: Active mm², Earth mm², Rating A A, Type B m, Type C m, Type D m, Fuse m

These are the values AmpSize encodes. No text of the standard is reproduced. Verify against the current standard.

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20 rows

B1, Maximum route lengths for conductor sizes and protective devices
Active (mm²)	Earth (mm²)	Rating A	Type B (m)	Type C (m)	Type D (m)	Fuse (m)
1	1	6	170	91	55	204
1	1	10	102	55	33	114
1.5	1.5	10	153	82	49	170
1.5	1.5	16	96	51	31	82
2.5	2.5	16	160	85	51	136
2.5	2.5	20	128	68	41	93
4	2.5	25	126	67	40	90
4	2.5	32	98	52	31	70
6	2.5	40	90	48	29	60
10	4	50	117	62	37	73
16	6	63	142	76	45	85
16	6	80	112	59	36	59
25	6	80	124	66	40	66
25	6	100	99	53	32	47
35	10	100	159	85	51	75
35	10	125	127	68	41	58
50	16	125	198	106	63	90
50	16	160	155	83	50	71
70	25	160	235	126	75	108
70	25	200	188	100	60	84

Tools that read it (1)

Maximum Circuit Length

Cables

Protection

Loads

Power

Solar

Safety

Earthing

Testing

Fire

Regulatory

B1

Tools that read it (1)

Guides and learn pages that cite it (2)

Active (mm²)	Earth (mm²)	Rating A	Type B (m)	Type C (m)	Type D (m)	Fuse (m)
1	1	6	170	91	55	204
1	1	10	102	55	33	114
1.5	1.5	10	153	82	49	170
1.5	1.5	16	96	51	31	82
2.5	2.5	16	160	85	51	136
2.5	2.5	20	128	68	41	93
4	2.5	25	126	67	40	90
4	2.5	32	98	52	31	70
6	2.5	40	90	48	29	60
10	4	50	117	62	37	73
16	6	63	142	76	45	85
16	6	80	112	59	36	59
25	6	80	124	66	40	66
25	6	100	99	53	32	47
35	10	100	159	85	51	75
35	10	125	127	68	41	58
50	16	125	198	106	63	90
50	16	160	155	83	50	71
70	25	160	235	126	75	108
70	25	200	188	100	60	84

Active (mm²)	Earth (mm²)	Rating A	Type B (m)	Type C (m)	Type D (m)	Fuse (m)
1	1	6	170	91	55	204
1	1	10	102	55	33	114
1.5	1.5	10	153	82	49	170
1.5	1.5	16	96	51	31	82
2.5	2.5	16	160	85	51	136
2.5	2.5	20	128	68	41	93
4	2.5	25	126	67	40	90
4	2.5	32	98	52	31	70
6	2.5	40	90	48	29	60
10	4	50	117	62	37	73
16	6	63	142	76	45	85
16	6	80	112	59	36	59
25	6	80	124	66	40	66
25	6	100	99	53	32	47
35	10	100	159	85	51	75
35	10	125	127	68	41	58
50	16	125	198	106	63	90
50	16	160	155	83	50	71
70	25	160	235	126	75	108
70	25	200	188	100	60	84

Active (mm²)	Earth (mm²)	Rating A	Type B (m)	Type C (m)	Type D (m)	Fuse (m)
1	1	6	170	91	55	204
1	1	10	102	55	33	114
1.5	1.5	10	153	82	49	170
1.5	1.5	16	96	51	31	82
2.5	2.5	16	160	85	51	136
2.5	2.5	20	128	68	41	93
4	2.5	25	126	67	40	90
4	2.5	32	98	52	31	70
6	2.5	40	90	48	29	60
10	4	50	117	62	37	73
16	6	63	142	76	45	85
16	6	80	112	59	36	59
25	6	80	124	66	40	66
25	6	100	99	53	32	47
35	10	100	159	85	51	75
35	10	125	127	68	41	58
50	16	125	198	106	63	90
50	16	160	155	83	50	71
70	25	160	235	126	75	108
70	25	200	188	100	60	84