Copper bar (copper bus) ampacity
Skin effect
The skin effect is also called the skin effect. When an alternating current passes through the conductor, the current will concentrate on the surface of the conductor and this phenomenon is called the skin effect. Because when an alternating current flows through the wire, an electromotive force in the direction opposite to the current will be generated inside the wire.
Since the center of the wire is larger than the flux linkage on the surface of the wire, the electromotive force generated at the center of the wire is greater than that generated near the surface of the wire. As a result of this action, the current flows on the surface and there is no current in the center. This magnetic field generated by the current of the wire itself causes the wire current to flow on the surface.
Considering the skin effect of alternating current, in order to effectively use conductor materials and facilitate heat dissipation, the high-current busbars of power plants are often made into troughs or diamond-shaped busbars; in addition, steel core aluminum stranded wires are used in high-voltage transmission and distribution lines. Aluminum stranded wire not only saves the aluminum wire, but also increases the mechanical strength of the wire.
These all use the principle of skin effect.
List of single copper busbar specifications and current carrying capacity (the maximum allowable temperature of copper busbar is 70℃)
Copper bus bar size (cross section,mm) |
copper(A) |
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AC (ambient temperature) |
DC (ambient temperature) |
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25℃ |
30℃ |
35℃ |
40℃ |
25℃ |
30℃ |
35℃ |
40℃ |
|
15 x 3* |
210 |
197 |
185 |
170 |
210 |
197 |
185 |
170 |
20 x 3* |
275 |
258 |
242 |
223 |
275 |
258 |
242 |
223 |
25 x 3* |
340 |
320 |
299 |
276 |
340 |
320 |
299 |
276 |
30 x 4* |
475 |
446 |
418 |
385 |
475 |
446 |
418 |
385 |
40 x 4* |
625 |
587 |
550 |
506 |
625 |
587 |
550 |
506 |
40 x 5 |
700 |
659 |
615 |
567 |
705 |
664 |
620 |
571 |
50 x 5* |
860 |
809 |
756 |
697 |
870 |
818 |
765 |
705 |
50 x 6 |
955 |
898 |
840 |
774 |
960 |
902 |
845 |
778 |
63 x 6* |
1125 |
1056 |
990 |
912 |
1145 |
1079 |
1010 |
928 |
80 x 6 |
1480 |
1390 |
1300 |
1200 |
1510 |
1420 |
1330 |
1225 |
100 x 6 |
1810 |
1700 |
1590 |
1470 |
1875 |
1760 |
1650 |
1520 |
60 x 8* |
1320 |
1240 |
1160 |
1070 |
1345 |
1265 |
1185 |
1090 |
80 x 8* |
1690 |
1590 |
1490 |
1370 |
1755 |
1650 |
1545 |
1420 |
100 x 8 |
2080 |
1955 |
1830 |
1685 |
2180 |
2050 |
1920 |
1770 |
125 x 8 |
2400 |
2255 |
2110 |
1945 |
2600 |
2445 |
2290 |
2105 |
60 x 10 |
1475 |
1388 |
1300 |
1195 |
1525 |
1432 |
1340 |
1235 |
80 x 10 |
1900 |
1786 |
1670 |
1540 |
1990 |
1870 |
1750 |
1610 |
100 x 10* |
2310 |
2170 |
2030 |
1870 |
2470 |
2320 |
2175 |
2000 |
125 x 10 |
2650 |
2490 |
2330 |
2150 |
2950 |
2770 |
2595 |
2390 |
Note: 1. This table is the data of copper bus bar standing. When the copper bus bar is flat and the width is ≤63mm, the data in the table should be multiplied by 0.95, and >63mm should be multiplied by 0.92. |
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2. The ones with "*" are the preferred specifications. |
Contact: Leanne
Phone: 0086-13853146766
Tel: 0086-13853146766
Company: LJMC
Add: 4th floor,Pingan group industrail park,Pingan street office,Jinan city ,Shandong