Cubic Power System's develop and fabricate the Bus Duct systems, air insulated, nonsegregated construction. Designed, fabricated and erected for various power plants Our Bus Tie Ducts (BTD) are designed to meet the required voltage, ampere and fault levels ratings. The Bus Tie Ducts (BTD) and rising mains are reliable, durable and available at highly cost effective prices. Copper bus bars are sized in accordance with the specified ratings to operate within IEC standard and temperature rise limits.