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Technical Information for :

Flat Twin & Earth BS6004
Flat Three Core & Earth BS6004

Ambient temperature : 30ºC
Conductor operating temperature : 70ºC

CURRENT-CARRYING CAPACITY (AMPS)
Conductor cross sectional area	enclosed in an insulated wall		enclosed in conduit on a wall or in trunking etc.		clipped direct
1.0mm²	11A	10A	13A	11.5A	15A	13.5A
1.5mm²	14A	13A	16.5A	15A	19.5A	17.5A
2.5mm²	18.5A	17.5A	23A	20A	27A	24A
4.0mm²	25A	23A	30A	27A	36A	32A
6.0mm²	32A	29A	38A	34A	46A	41A
10.0mm²	43A	39A	52A	46A	63A	57A
16.0mm²	57A	52A	69A	62A	85A	76A

VOLTAGE DROP (PER AMPERE PER METRE)
Conductor cross sectional area	Two-core d.c.	Two-core cable single phase a.c.	Three or four core cable three phase a.c.
1.0mm²	44mV	44mV	38mV
1.5mm²	29mV	29mV	25mV
2.5mm²	18mV	18mV	15mV
4.0mm	11V	11mV	9.5mV
6.0mm²	7.3mV	7.3mV	6.4mV
10.0mm²	4.4mV	4.4mV	3.8mV
16.0mm²	2.8mV	2.8mV	2.4mV

If cables are to be used in ambient air temperature other than 30ºC the following rating factors should be applied
Ambient air temperature °C	25	30	35	40	45	50	55	60	65
Rating Factor	1.03	1.0	0.94	0.87	0.79	0.71	0.61	0.50	0.35

XLPE/PVC/SWA/PVC ARMOURED CABLE

CURRENT CARRYING CAPACITY (AMPS)
Direct Burial			In Single-Way Duct			Air
Nominal conductor area	2 Core	3 & 4 Core	Nominal conductor area	2 Core	3 & 4 Core	Nominal conductor area	2 Core	3 & 4 Core
1.5mm²	38	32	1.5mm²	31	26	1.5mm²	31	26
2.5mm²	49	42	2.5mm²	41	34	2.5mm²	41	35
4.0mm²	65	55	4.0mm²	53	45	4.0mm²	55	47
6.0mm²	81	69	6.0mm²	67	56	6.0mm²	70	59
10.0mm²	109	92	10.0mm²	89	75	10.0mm²	95	82
16.0mm²	141	119	16.0mm²	115	96	16.0mm²	126	107
25.0mm²	183	152	25.0mm²	148	124	25.0mm²	164	140
35.0mm²	219	182	35.0mm²	178	149	35.0mm²	202	172
50.0mm²	259	217	50.0mm²	211	177	50.0mm²	244	209
70.0mm²	317	266	70.0mm²	260	218	70.0mm²	306	263
95.0mm²	381	319	95.0mm²	313	263	95.0mm²	378	324
120.0mm²	433	363	120.0mm²	357	300	120.0mm²	437	376
150.0mm²	485	406	150.0mm²	401	338	150.0mm²	499	430
185.0mm²	547	458	185.0mm²	455	382	185.0mm²	576	495
240.0mm²	632	529	240.0mm²	527	442	240.0mm²	680	584
300.00mm²	708	592	300.00mm²	592	496	300.00mm²	775	666
400.00mm²	799	667	400.00mm²	669	570	400.00mm²	892	766

    Standard depth of laying                    0.5m
    Thermal resistivity of soil                    1.2°C m/W
    Standard ground temperature            15°C
    Ambient air temperature                    25°C
    Maximum conductor temperature      90°C
    For 2 core - single phase a.c., 3 & 4 core - three phase a.c. ratings do not apply if the cable is protected by a semi-enclosed fuse to BS3036.

For cables of 5 cores and above it is assumed only 2 cores are loaded simultaneously (ie live and neutral) and the 2 core rating should be taken. In instances where several cores are loaded simultaneously, the following rating factors should be applied to the 2 core current rating:

Number of cores	2	3	4	5	6	7	10	12	-
Factor	1.0	0.87	0.78	0.72	0.67	0.63	0.56	0.53	-
Number of cores	14	19	24	27	30	37	44	46	48
Factor	0.51	0.45	0.42	0.40	0.39	0.36	0.34	0.33	0.33

For cables laid in air temperatures other than those specified the following rating factors should be applied:

Ambient air temp ºC	25	30	35	40	45	50	55
Rating Factor	1.0	0.96	0.92	0.88	0.83	0.78	0.73

For cables laid in ground and single way ducts with temperatures other than those specified the following rating factors should be applied:

Ambient air temp ºC	10	15	20	25	30	35	40
Rating Factor	1.03	1.0	0.97	0.93	0.89	0.86	0.82

VOLTAGE DROP (AMPS PER METRE)
Conductor cross sectional area	Two core cable d.c.	Two core cable single phase a.c.			Three or four core cable three phase a.c.
1.5mm²	31mV	31mV			27mV
2.5mm²	19mV	19mV			16mV
4.0mm²	12mV	12mV			10mV
6.0mm²	7.9mV	7.9mV			6.8mV
10.0mm²	4.7mV	4.7mV			4.0mV
16.0mm²	2.9mV	2.9mV			2.5mV
		r	x	z	r	x	z
25.0mm²	1.85mV	1.85mV	0.160mV	1.90mV	1.60mV	0.140mV	1.65mV
35.0mm²	1.35mV	1.35mV	0.155mV	1.35mV	1.15mV	0.135mV	1.15mV
50.0mm²	0.98mV	0.99mV	0.155mV	1.00mV	0.86mV	0.135mV	0.87mV
70.0mm²	0.67mV	0.67mV	0.150mV	0.69mV	0.59mV	0.130mV	0.60mV
95.0mm²	0.49mV	0.50mV	0.150mV	0.52mV	0.43mV	0.130mV	0.45mV
120.0mm²	0.39mV	0.40mV	0.145mV	0.42mV	0.34mV	0.130mV	0.37mV
150.0mm²	0.31mV	0.32mV	0.145mV	0.35mV	0.28mV	0.125mV	0.30mV
185.0mm²	0.25mV	0.26mV	0.145mV	0.29mV	0.22mV	0.125mV	0.26mV
240.0mm²	0.195mV	0.20mV	0.140mV	0.24mV	0.175mV	0.125mV	0.21mV
300.0mm²	0.155mV	0.16mV	0.140mV	0.21mV	0.140mV	0.120mV	0.185mV
400.0mm²	0.120mV	0.13mV	0.145mV	0.195mV	0.115mV	0.125mV	0.170mV