What is the permissible current density in the armature conductors?

The permissible current density in armature conductors varies depending on several factors including the type of cooling, the material of the conductors, and the design of the electrical machine (such as a motor or generator). Typically, for electrical machines like motors and generators, the current density can range from about 3 to 6 A/mm^2 for copper conductors under normal operating conditions. However, these values can be higher or lower based on the specific application requirements, cooling methods used (air cooling, liquid cooling, etc.), and the design margins for temperature rise and efficiency. Engineers determine the exact permissible current density during the design phase to ensure optimal performance, longevity, and safety of the machine. Always refer to specific design guidelines and standards relevant to the application for the most accurate information.