Circular non-segregated bus duct
The metal-clad bus duct described in this section is a non-segregated 3-phases bus duct designed, and CSA approved, for operation on 4.16KV, 13.8KV and 34.5KV systems. The bus duct comprises three tubular aluminum or copper bus bars arranged in a triangular configuration within a tubular aluminum enclosure. The bus bars are supported within the enclosure by a delta clamp assembly.
- Inherent mechanical strength of the combination tubular and triangular configuration.
- Reduced weight – approximately two thirds less than previous steel and copper rectangular design.
- Triangular bus arrangement gives equalization of reactance between phases – no phase transposition required on long runs.
- Non-ventilated – no problem of dust or dirt build-up on bus insulation and supports.
- Flexibility – length of individual enclosure sections limited only by customer’s handling facilities – bends can be to any angle (not limited to 90° or 45°) – each field joint has a linear adjustment of plus or minus 1.0 inch.
Insulation used in the construction of metal-clad bus ducts is designed to withstand hipot, impulse and corona tests identical to those used on metal-clad switchgear.