Ampacity

[ScubaSteve]

The rated electrical current-carrying capacity for a conductor, or in our case the windings around a stator as well as the leads from the motor to the ESC and from the ESC to the power source.

Heating is caused by the electric current flowing through the windings. Copper and aluminum wire can conduct a large amount of current before melting but long before the conductors melt, their insulation would be damaged by the heat. So the ampacity of a given wire is set by the maximum temperature that the insulation can withstand forever. For common plastic insulations, this may be 60, 90, or 105 degrees Celsius. Bundling multiple wires together increases the amount of heating while decreasing the convection cooling of the insulation; this has the effect of reducing the ampacity for wires in bundles. For example, the National Electric Code specifies that a single 8 AWG (8 gauge) copper wire with common insulating material has an ampacity of 50 amps; this same wire's ampacity drops to 40 amps when bundled together in non-metallic sheathing with other conductors.

Related: AWG Data Chart

[JamesVT]

Do you have any charts or figures... sources to help understand this concept a little more.

[dsny]

Originally Posted by JamesVT

Do you have any charts or figures... sources to help understand this concept a little more.

There are thousands of articles on ampacity for conductors but I have never found any details on the wire used in our motors or any explanation as to why a tiny little one ounce motor can consume 60A and not melt down. Do a Google search on Ampacity and you will find about two months worth of steady reading material.
Dan