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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 AreaReference 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 touching3 or 4 cables, three-phase a.c. flat and touching or trefoil2 cables, single-phase a.c. or d.c. flat3 cables, three-phase a.c. flat3 cables, three-phase a.c. trefoil2 cables, single-phase a.c. or d.c. or 3 cables three-phase a.c. flat
HorizontalVertical
123456789101112
(mm2)(A)(A)(A)(A)(A)(A)(A)(A)(A)(A)(A)
1141317151917.5-----
1.5191723202523-----
2.5262331283431-----
4353142374641-----
6454054485954-----
10615475668174-----
1681731008810999-----
2510695133117143130161141135182161
35131117164144176161200176169226201
50158141198175228209242216207275246
70200179253222293268310279268353318
95241216306269355326377342328430389
120278249354312413379437400383500454
1503182853933424764036504464444577527
185362324449384545500575533510661605
240424380528450644590679634607781719
300486435603514743681783736703902833
400--6835848687939408688231,0851,008
500--7836669909041,0839989461,2531,169
630--9007641,1301,0331,2541,1511,0881,4541,362
800----1,2881,1791,3581,2751,2141,5811,485
1,000----1,4431,3231,5201,4361,3491,7751,671

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 Area2 cables d.c2 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 touchingCables spaced*Cables touching, trefoilCables touching, flatCables spaced*, flat
123456789
(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)
14646464640404040
1.53131313127272727
2.51919191916161616
41212121210101010
67.97.97.97.96.86.86.86.8
104.74.74.74.74444
162.92.92.92.92.52.52.52.5
  rxzrxzrxzrxzrxzrxzrxz
251.851.850.311.91.850.191.851.850.281.851.60.271.651.61.1651.61.60.191.61.60.271.65
351.351.350.291.351.350.181.351.350.271.351.150.251.151.150.1551.151.150.181.151.150.261.2
500.9910.291.050.990.1810.990.2710.870.250.90.860.1550.870.860.180.870.860.260.89
700.680.70.280.750.680.1750.710.680.260.730.60.240.650.590.150.610.590.1750.620.590.250.65
950.490.510.270.580.490.170.520.490.260.560.440.230.50.430.1450.450.430.170.460.430.250.49
1200.390.410.260.480.390.1650.430.390.250.470.350.230.420.340.140.370.340.1650.380.340.240.42
1500.320.330.260.430.320.1650.360.320.250.410.290.230.370.280.140.310.280.1650.320.280.240.37
1850.250.270.260.370.260.1650.30.250.250.360.230.230.320.220.140.260.220.1650.280.220.240.33
2400.190.210.260.330.20.160.250.1950.250.310.1850.220.290.170.140.220.170.1650.240.170.240.29
3000.1550.1750.250.310.160.160.220.1550.250.290.150.220.270.140.140.1950.1350.160.210.1350.240.27
4000.120.140.250.290.130.1550.20.1250.240.270.1250.220.250.110.1350.1750.110.160.1950.110.240.26
5000.0930.120.250.280.1050.1550.1850.0980.240.260.10.220.240.090.1350.160.0880.160.180.0850.240.25
6300.0720.10.250.270.0860.1550.1750.0780.240.250.0880.210.230.0740.1350.150.0710.160.170.0680.230.24
8000.056 - 0.0720.150.170.0640.240.25 - 0.0620.130.1450.0590.1550.1650.0550.230.24
1,0000.045 - 0.0630.150.1650.0540.240.24 - 0.0550.130.140.050.1550.1650.0470.230.24

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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