Single Core 70°C Thermoplastic Insulated Cables, Non Armoured, With or Without Sheath (COPPER CONDUCTORS)

Tables Apply to: ST91X, 6491X, 6181Y, TRI-RATED (when installed in conduit or trunking)

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 horizontal or vertical etc.)
							Touching			Spaced by one diameter
	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	11	10.5	13.5	12	15.5	14	-	-	-	-	-
1.5	14.5	13.5	17.5	15.5	20	18	-	-	-	-	-
2.5	20	18	24	21	27	25	-	-	-	-	-
4	26	24	32	28	37	33	-	-	-	-	-
6	34	31	41	36	47	43	-	-	-	-	-
10	46	42	57	50	65	59	-	-	-	-	-
16	61	59	76	68	87	79	-	-	-	-	-
25	80	73	101	89	114	104	131	114	110	146	130
35	99	89	125	110	141	129	162	143	137	181	162
50	119	108	151	134	182	167	196	174	167	219	197
70	151	136	192	171	234	214	251	225	216	281	254
95	182	164	232	207	284	261	304	275	264	341	311
120	210	188	269	239	330	303	352	321	308	396	362
150	240	216	300	262	381	349	406	372	356	456	419
185	273	245	341	296	436	400	463	427	409	521	480
240	321	286	400	346	515	472	546	507	485	615	569
300	367	328	458	394	594	545	629	587	561	709	659
400	-	-	546	467	694	634	754	689	656	852	795
500	-	-	626	533	792	723	868	789	749	982	920
630	-	-	720	611	904	826	1,005	905	855	1,138	1,070
800	-	-	-	-	1,030	943	1,086	1,020	971	1,265	1,188
1000	-	-	-	-	1,154	1,058	1,216	1,149	1,079	1,420	1,337

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 (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	44	44			44			44			38			38			38			38
1.5	29	29			29			29			25			25			25			25
2.5	18	18			18			18			15			15			15			15
4	11	11			11			11			9.5			9.5			9.5			9.5
6	7.3	7.3			7.3			7.3			6.4			6.4			6.4			6.4
10	4.4	4.4			4.4			4.4			3.8			3.8			3.8			3.8
16	2.8	2.8			2.8			2.8			2.4			2.4			2.4			2.4
		r	x	z	r	x	z	r	x	z	r	x	z	r	x	z	r	x	z	r	x	z
25	1.75	1.8	0.33	1.8	1.75	0.2	1.75	1.75	0.29	1.8	1.5	0.29	1.55	1.5	0.175	1.5	1.5	0.25	1.55	1.5	0.32	1.55
35	1.25	1.3	0.31	1.3	1.25	0.195	1.25	1.25	0.28	1.3	1.1	0.27	1.1	1.1	0.17	1.1	1.1	0.24	1.1	1.1	0.32	1.15
50	0.93	0.95	0.3	1	0.93	0.19	0.95	0.93	0.28	0.97	0.81	0.26	0.85	0.8	0.165	0.82	0.8	0.24	0.84	0.8	0.32	0.86
70	0.63	0.65	0.29	0.72	0.63	0.185	0.66	0.63	0.27	0.69	0.56	0.25	0.61	0.55	0.16	0.57	0.55	0.24	0.6	0.55	0.31	0.51
95	0.46	0.49	0.28	0.56	0.47	0.18	0.5	0.47	0.27	0.54	0.42	0.24	0.48	0.41	0.155	0.43	0.41	0.23	0.47	0.4	0.31	0.51
120	0.36	0.39	0.27	0.47	0.37	0.175	0.41	0.37	0.26	0.45	0.33	0.23	0.41	0.32	0.15	0.36	0.32	0.23	0.4	0.32	0.3	0.44
150	0.29	0.31	0.27	0.41	0.3	0.175	0.34	0.29	0.26	0.39	0.27	0.23	0.36	0.26	0.15	0.3	0.26	0.23	0.34	0.26	0.3	0.4
185	0.23	0.25	0.27	0.37	0.24	0.17	0.29	0.24	0.26	0.35	0.22	0.23	0.32	0.21	0.145	0.26	0.21	0.22	0.31	0.21	0.3	0.36
240	0.18	0.195	0.26	0.33	0.195	0.165	0.25	0.185	0.25	0.31	0.17	0.23	0.29	0.16	0.145	0.22	0.16	0.22	0.27	0.16	0.29	0.34
300	0.145	0.16	0.26	0.31	0.15	0.165	0.22	0.15	0.25	0.29	0.14	0.23	0.27	0.13	0.14	0.19	0.13	0.22	0.25	0.13	0.29	0.32
400	0.105	0.13	0.26	0.29	0.12	0.16	0.2	0.115	0.25	0.27	0.12	0.22	0.25	0.105	0.14	0.175	0.105	0.21	0.24	0.1	0.29	0.31
500	0.086	0.11	0.26	0.27	0.098	0.155	0.185	0.093	0.24	0.26	0.1	0.22	0.25	0.086	0.135	0.16	0.086	0.21	0.23	0.081	0.29	0.3
630	0.068	0.094	0.25	0.27	0.081	0.155	0.175	0.076	0.24	0.25	0.08	0.22	0.24	0.072	0.135	0.15	0.072	0.21	0.22	0.066	0.28	0.29
800	0.053	-			0.068	0.15	0.165	0.061	0.24	0.25	-			0.06	0.13	0.145	0.06	0.21	0.22	0.053	0.28	0.29
1000	0.042	-			0.059	0.15	0.16	0.05	0.24	0.24	-			0.052	0.13	0.14	0.052	0.2	0.21	0.044	0.28	0.28

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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