Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Base Ampacity Amperes (A)

Required number input.

Installation Factor

Required number input.

Temperature Factor

Required number input.

Usable conductor current rating from a supplied base ampacity times installation and temperature derating factors; not a code sizing determination. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Adjusted Ampacity Amperes (A)

The resulting adjusted ampacity amperes returned as a number.

• Conductor ampacity and diameter selection depends on material, insulation rating, ambient temperature, bundling, installation method, terminals, voltage drop, fault current, harmonics, and applicable electrical code. A geometric conversion does not establish a safe circuit rating.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Ampacity Derated

  Adjusted current rating from a base ampacity times a supplied 0–1 derating factor; not a code sizing result.

• Bolt Shear Capacity

  Nominal single-shear force from bolt shear area times a user-supplied allowable shear stress; not a code-rated connection capacity.

• Bolt Tensile Capacity

  Nominal axial force from bolt tensile stress area times a user-supplied allowable tensile stress; excludes prying and interaction.