Electrical - current carrying of cables

Copper Conductors Single core 70⁰C thermoplastic insulated cables (e.g. PVC Singles), non-armoured with or without sheath.  All values assume an ambient temperature of 30⁰C and a conductor operating temperature of 70⁰C.

Conductor CSA	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)
							Touching			Spaced by one diameter
										2 cables, 1ph ac or dc flat 3 cables, 3ph ac flat
	2 cables, 1ph ac or dc	3 or 4 cables, 3ph ac	2 cables, 1ph ac or dc	3 or 4 cables, 3ph ac	2 cables, 1ph ac or dc	3 or 4 cables, 3ph ac	2 cables, 1ph ac or dc flat	3 cables 3ph ac flat	3 cables, 3ph ac  trefoil	Horizontal	Vertical
1mm2	11	10.5	13.5	12	15.5	14
1.5mm2	14.5	13.5	17.5	15.5	20	18
2.5mm2	20	18	24	21	27	25
4mm2	26	24	32	28	37	33
6mm2	34	31	41	36	47	43
10mm2	46	42	57	50	65	59
16mm2	61	56	76	68	87	79
25mm2	80	73	101	89	114	104	131	114	110	146	130
35mm2	99	89	125	110	141	129	162	143	137	181	162

 

Table 4D2A – Multicore 70⁰c thermoplastic insulated & thermoplastic sheathed cables (e.g. PVC T&E), nonarmoured.  All values assume an ambient temperature of 30⁰c and a conductor operating temperature of 70⁰c.

Conductor CSA	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 E (in free air or on a perforated cable tray, horizontal or vertical)
	1 two core cable*, 1ph ac or dc	1 three core cable* or 1 four core cable, 3ph ac	1 two core cable*, 1ph ac or dc	1 three core cable* or 1 four core cable, 3ph ac	1 two core cable*, 1ph ac or dc	1 three core cable* or 1 four core cable, 3ph ac	1 two core cable*, 1ph ac or dc	1 three core cable* or 1 four core cable, 3ph ac
1mm2	11	10	13	11.5	15	13.5	17	14.5
1.5mm2	14	13	16.5	15	19.5	17.5	22	18.5
2.5mm2	18.5	17.5	23	20	27	24	30	25
4mm2	25	23	30	27	36	32	40	34
6mm2	32	29	38	34	46	41	51	43
10mm2	43	39	52	46	63	57	70	60
16mm2	57	52	69	62	85	76	94	80

*with or without a protective conductor

Multicore 70⁰c armoured thermoplastic insulated cables (e.g. SWA cable).  All values assume that air ambient temperature of 30⁰c, ground ambient temperature of 20⁰c & conductor operating temperature of 70⁰c.

Conductor CSA	Reference Method C (clipped direct)		Reference Method E (in free air or on a perforated cable tray, horizontal or vertical)		Reference Method D (direct in ground or in ducting in ground, in or around buildings)
	1 two core cable, 1ph ac or dc	1 three core cable or 1 four core cable, 3ph ac	1 two core cable, 1ph ac or dc	1 three core cable or 1 four core cable, 3ph ac	1 two core cable, 1ph ac or dc	1 three core cable or 1 four core cable, 3ph ac
1.5mm2	21	18	22	19	22	18
2.5mm2	28	25	31	26	29	24
4mm2	38	33	41	35	37	30
6mm2	49	42	53	45	46	38
10mm2	67	58	72	62	60	50
16mm2	89	77	97	83	78	64
25mm2	118	102	128	110	99	82
35mm2	145	125	157	135	119	98
50mm2	175	151	190	163	140	116
70mm2	222	192	241	207	173	143
95mm2	269	231	291	251	204	169

Flexible cords, non-armoured

Conductor CSA (mm2)	Current carrying capacity		Max. supported weight (Kg) See Regs 522.7.2 & 559.6.1.5
	1ph ac	3ph ac
0.5mm2	3	3	2
0.75mm2	6	6	3
1mm2	10	10	5
1.25mm2	13	-	5
1.5mm2	16	16	5
2.5mm2	25	20	5
4mm2	32	25	5