Procedure for determination of the ampacity tables

For the test set-up the PCBs were measured in a temperature-controlled loading gage at a constant environmental temperature of 22 C°.

Solder pads were used for the power supply. The different currents are applied for five minutes to stabilise the thermal gradients, after which an infrared image was recorded.

For the test series following experimental set-up was carried out:

  • FR4 base material
  • „PCB thickness: 2.2 – 2.5 mm
  • PCB profile: 115 x 80 mm²
  • Equal copper flooding of 40 % on each layer

The following tables serve as rough guides as the ampacity is determined and influenced by the layout, stack up, assembled components and other factors. Therefore the build-up and design needs to be evaluated by the product manager for the specific project.

For more than four F14 wires the following may be considered: 12 A per wire at ΔT = 20 K

Ampacity tables

Wires welded under the external layer

Wires welded under the internal layer

Any more questions? For higher currents please contact our product management at