Single Core 90°C Thermosetting Insulated Cables, Unarmoured, With or Without Sheath (COPPER CONDUCTORS)

Tables Apply to: 6491B, 6181XY

CURRENT-CARRYING CAPACITY (amperes)

Conductor Cross Sectional Area	Reference Method A (enclosed in conduit in thermally insulating wall etc.)		Reference Method B (enclosed in conduit on a wall or in trunking etc.)		Reference Method C (clipped direct)		Reference Method F (in free air or on a perforated cable tray etc horizontal or vertical etc.)			Reference Method G (in free air)
	2 cables, single-phase a.c. or d.c.	3 or 4 cables, three-phase a.c.	2 cables, single-phase a.c. or d.c.	3 or 4 cables, three-phase a.c.	2 cables, single-phase a.c. or d.c. flat and touching	3 or 4 cables, three-phase a.c. flat and touching or trefoil	2 cables, single-phase a.c. or d.c. flat	3 cables, three-phase a.c. flat	3 cables, three-phase a.c. trefoil	2 cables, single-phase a.c. or d.c. or 3 cables three-phase a.c. flat
										Horizontal	Vertical
1	2	3	4	5	6	7	8	9	10	11	12
(mm2)	(A)	(A)	(A)	(A)	(A)	(A)	(A)	(A)	(A)	(A)	(A)
1	14	13	17	15	19	17.5	-	-	-	-	-
1.5	19	17	23	20	25	23	-	-	-	-	-
2.5	26	23	31	28	34	31	-	-	-	-	-
4	35	31	42	37	46	41	-	-	-	-	-
6	45	40	54	48	59	54	-	-	-	-	-
10	61	54	75	66	81	74	-	-	-	-	-
16	81	73	100	88	109	99	-	-	-	-	-
25	106	95	133	117	143	130	161	141	135	182	161
35	131	117	164	144	176	161	200	176	169	226	201
50	158	141	198	175	228	209	242	216	207	275	246
70	200	179	253	222	293	268	310	279	268	353	318
95	241	216	306	269	355	326	377	342	328	430	389
120	278	249	354	312	413	379	437	400	383	500	454
150	318	285	393	342	476	4036	504	464	444	577	527
185	362	324	449	384	545	500	575	533	510	661	605
240	424	380	528	450	644	590	679	634	607	781	719
300	486	435	603	514	743	681	783	736	703	902	833
400	-	-	683	584	868	793	940	868	823	1,085	1,008
500	-	-	783	666	990	904	1,083	998	946	1,253	1,169
630	-	-	900	764	1,130	1,033	1,254	1,151	1,088	1,454	1,362
800	-	-	-	-	1,288	1,179	1,358	1,275	1,214	1,581	1,485
1,000	-	-	-	-	1,443	1,323	1,520	1,436	1,349	1,775	1,671

NOTES :

• Where a conductor operates at a temperature exceeding 70°C it must be ascertained that the equipment connected to the conductor is suitable for the conductor operating temperature (see Regulation 512.1.2)
• Where cables in this table are connected to equipment or accessories designed to operate at a temperature not exceeding 70°C, the current ratings given in the equivalent table for 70°C thermoplastic insulated cables (Table 4D1A) must be used (see also Regulation 523.1)

VOLTAGE DROP (per ampere per metre)

Conductor Cross Sectional Area	2 cables d.c	2 cables, single-phase a.c.									3 or 4 cables, three-phase a.c.
		Reference Methods A&B (enclosed in trunking)			Reference Methods C&F (clipped direct, on tray, or in free air)						Reference Methods A&B (enclosed in conduit or trunking)			Reference Methods C,F & G (clipped direct, on tray or in free air)
					Cables touching			Cables spaced*						Cables touching, trefoil			Cables touching, flat			Cables spaced*, flat
1	2	3			4			5			6			7			8			9
(mm2)	(mV/A/m)	(mV/A/m)			(mV/A/m)			(mV/A/m)			(mV/A/m)			(mV/A/m)			(mV/A/m)			(mV/A/m)
1	46	46			46			46			40			40			40			40
1.5	31	31			31			31			27			27			27			27
2.5	19	19			19			19			16			16			16			16
4	12	12			12			12			10			10			10			10
6	7.9	7.9			7.9			7.9			6.8			6.8			6.8			6.8
10	4.7	4.7			4.7			4.7			4			4			4			4
16	2.9	2.9			2.9			2.9			2.5			2.5			2.5			2.5
		r	x	z	r	x	z	r	x	z	r	x	z	r	x	z	r	x	z	r	x	z
25	1.85	1.85	0.31	1.9	1.85	0.19	1.85	1.85	0.28	1.85	1.6	0.27	1.65	1.6	1.165	1.6	1.6	0.19	1.6	1.6	0.27	1.65
35	1.35	1.35	0.29	1.35	1.35	0.18	1.35	1.35	0.27	1.35	1.15	0.25	1.15	1.15	0.155	1.15	1.15	0.18	1.15	1.15	0.26	1.2
50	0.99	1	0.29	1.05	0.99	0.18	1	0.99	0.27	1	0.87	0.25	0.9	0.86	0.155	0.87	0.86	0.18	0.87	0.86	0.26	0.89
70	0.68	0.7	0.28	0.75	0.68	0.175	0.71	0.68	0.26	0.73	0.6	0.24	0.65	0.59	0.15	0.61	0.59	0.175	0.62	0.59	0.25	0.65
95	0.49	0.51	0.27	0.58	0.49	0.17	0.52	0.49	0.26	0.56	0.44	0.23	0.5	0.43	0.145	0.45	0.43	0.17	0.46	0.43	0.25	0.49
120	0.39	0.41	0.26	0.48	0.39	0.165	0.43	0.39	0.25	0.47	0.35	0.23	0.42	0.34	0.14	0.37	0.34	0.165	0.38	0.34	0.24	0.42
150	0.32	0.33	0.26	0.43	0.32	0.165	0.36	0.32	0.25	0.41	0.29	0.23	0.37	0.28	0.14	0.31	0.28	0.165	0.32	0.28	0.24	0.37
185	0.25	0.27	0.26	0.37	0.26	0.165	0.3	0.25	0.25	0.36	0.23	0.23	0.32	0.22	0.14	0.26	0.22	0.165	0.28	0.22	0.24	0.33
240	0.19	0.21	0.26	0.33	0.2	0.16	0.25	0.195	0.25	0.31	0.185	0.22	0.29	0.17	0.14	0.22	0.17	0.165	0.24	0.17	0.24	0.29
300	0.155	0.175	0.25	0.31	0.16	0.16	0.22	0.155	0.25	0.29	0.15	0.22	0.27	0.14	0.14	0.195	0.135	0.16	0.21	0.135	0.24	0.27
400	0.12	0.14	0.25	0.29	0.13	0.155	0.2	0.125	0.24	0.27	0.125	0.22	0.25	0.11	0.135	0.175	0.11	0.16	0.195	0.11	0.24	0.26
500	0.093	0.12	0.25	0.28	0.105	0.155	0.185	0.098	0.24	0.26	0.1	0.22	0.24	0.09	0.135	0.16	0.088	0.16	0.18	0.085	0.24	0.25
630	0.072	0.1	0.25	0.27	0.086	0.155	0.175	0.078	0.24	0.25	0.088	0.21	0.23	0.074	0.135	0.15	0.071	0.16	0.17	0.068	0.23	0.24
800	0.056		-		0.072	0.15	0.17	0.064	0.24	0.25		-		0.062	0.13	0.145	0.059	0.155	0.165	0.055	0.23	0.24
1,000	0.045		-		0.063	0.15	0.165	0.054	0.24	0.24		-		0.055	0.13	0.14	0.05	0.155	0.165	0.047	0.23	0.24

NOTE: *Spacings larger than one cable diameter will result in a larger voltage drop.

DISCLAIMER: This information has been supplied in good faith and the upmost care has been taken to ensure the data is accurate in it's derivation from BS7671.
However, this information should not be considered as a substitute for BS7671, which should always be referred to. It remains the responsibility of the user to ensure all data and assumptions are correct and that any cable used is suitable for its intended purpose.

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