Notification 685 – Primary circular mils per amp low

CATEGORY

ISSUE / RESULT

FIX / REFERENCE(S)

Error

Calculated Primary circular mils per Amp is less than 150, this can also be equally identified as too high current density. When the current density is too high the wire may overheat. High temperature may prematurely degrade the wire insulation and cause a safety hazard.

In order to prevent overheating, a smaller wire gauge may be selected or a multiple stands winding may be used. All these fixes aim to increase the total equivalent copper area. The user may ultimately re-optimize the design. The optimization constraints will make sure the CMA is within the acceptable limits