Busway manufacturer and product series identifier used as the partition key in the busway-specs table (e.g., 'Siemens_Sentron', 'Eaton_Pow-R-Way').

Busway ampere rating in amps. Must match a rating in the busway-specs table (common: 225, 400, 600, 800, 1000, 1200, 1600, 2000, 3000, 4000, 5000 A).

Bus bar conductor material. Copper has lower resistance but higher cost; aluminum is lighter and less expensive. If omitted, defaults to 'copper'.

Product listing standard. UL 857 is the primary US standard for busways. Used as part of the table sort key. If omitted, defaults to 'UL 857'.

Total load current the busway must carry. Size busway for 80% continuous loading per NEC 220.87. Typical: 400-2000A for building feeders, 2000-6000A for datacenter power.

Total busway run length in meters. If omitted, length_ft must be provided instead.

Total busway run length in feet. If omitted, length_m must be provided instead.

System line-to-line voltage in volts. Common values: 208, 240, 480, 600 V. If omitted, defaults to 480 V.

Number of electrical phases. Affects the phase multiplier used in the voltage drop formula (sqrt(3) for 3-phase, 2 for single-phase). If omitted, defaults to 3.

Load power factor (lagging). Typical: 0.80-0.95 for mixed commercial loads, 0.90+ for modern IT equipment. If omitted, defaults to 0.85.

Load distribution pattern along the busway. 'end_fed' = full current over entire run; 'center_fed' or 'uniform_distributed' = effective length is halved. If omitted, defaults to 'end_fed'.

Maximum allowable voltage drop as a percentage of system voltage. NEC 210.19: 3% for branch circuits, 2% for feeders, 5% total. If omitted, defaults to 3.0%.