Electrical / Electronics
Historical insulated-copper ampacity
Historical data from a 1938 publication. Exact Iz lookup for educational and comparative use only.
Related calculators
Historical minimum copper section
Historical data from a 1938 publication. Smallest-section selection without interpolation, for educational and comparative use only.
Manual Iz compared with historical value
Compares manually entered Iz with the historical insulated-copper value without PASS/FAIL judgement.
Manual single-phase cable sizing check
Combines load current, manually corrected Iz, voltage drop and overload-condition checks.
Manual three-phase cable sizing check
Checks a balanced three-phase system with manually provided Iz, protective-device and voltage-drop data.
Exact Iz lookup from user table
Looks up base ampacity Iz only for an exactly entered section in the user-supplied table.
Single-phase selection from user table
Selects the smallest entered section that meets the manual current conditions and voltage-drop limit.