Current Ratings

In electronic cables, the maximum continuous current rating is limited by the size of the conductor, the total number of conductors within the cable, and conditions within the surrounding environment including ambient temperature and airflow.

To use the current capacity chart, determine the conductor size of the desired wire to be used, as well as the temperature rating and the number of conductors. Then find the current value on the chart for the proper temperature rating and conductor size. In order to calculate the maximum current rating per conductor, you have to multiply the chart value by the appropriate conductor factor found in the table below. This chart assumes that the cable is surrounded by still air at an ambient temperature of 25°C. These currency values are in RMS Amperes and are only valid for copper conductors. 

Conductor Current Ratings Chart

Note: Current ratings are intended as general guidelines for low power electronic communications and control applications. Current ratings for power applications generally are set by regulatory agencies such as UL, CSA, NEC, and others.

No. of Conductors* Factor
1 1.6
2 to 3 1.0
4 to 5 0.8
6 to 15 0.7
16 to 30 0.5

*Do not count shields unless used as the conductor