#CONCRETE ENCASED DUCT BANK INSTALL#

If the duct bank is 100 feet, then the total volume of concrete needed is 3.215 square feet times 100 feet, which equals 321.5 cubic feet of concrete. In any case a grounding conductor has to run along the cable duct bank for low voltage return fault current. Now multiply this number by the total length of the duct bank. By dividing 462.96 by 144, the result is 3.215 square feet.

#CONCRETE ENCASED DUCT BANK INSTALL#

The conduits we install can be used for primary, secondary or communications services. This is the cross-sectional area occupied by the concrete alone.Ĭonvert the cross-sectional area occupied by the concrete from square inches to square feet by dividing that number by 144. Wildcat Contractors installs both direct buried or concrete encased duct bank as part of your commercial, industrial or institutional project. So, 576-square inches minus 113.04 square inches equals 462.96 square inches. Subtract this number from the total cross sectional area of the duct bank. For a three-by-three, that is 3.14 times 4 times 9, which equals 113.04 square inches. The conduit area is pi times the radius squared times the number of conduits. The conduit area would be the cross-sectional area of one conduit times the number of conduits. For 99 of applications there is probably no need. 2), the following topics should be explored and evaluated to determine their relevance to the design. When designing large underground electrical duct banks (Fig. Now subtract from this number the total area occupied by the conduit. Concrete jacketed duct banks are not reinforced in my neck of the wood either. Typical concrete-encased duct bank detail highlighting the evaluated design considerations outlined in this article. Total Load: 2000 Amps (333.3 amps / cable) times 2 Cable/s: 750 Kcmil, RW90 Cu, Rated 90 C. In this three-by-three example, that would equal 24 inches times 24 inches or 576 square inches. Graph 3 - Both 2000 Amps Services in One Concrete Encasement Graph 4 - Two identical Duct Bank in Separate Trench, Enased in Concrete NUMBER OF CABLES System is rated for 75 Degrees C. Multiply the total width and total height. Since this is a three-by-three duct bank, its height will also be 24 inches.Ĭalculate the cross-sectional area of the duct bank. Repeat step 2 using the number of vertical conduits instead of the number of horizontal conduits. More Details (.Calculate the total height of the duct bank. This allows the duct bank to be quickly pre-assembled outside of the trench. These spacers can reduce the electro magnetic field at location up to 57%.įabricated Duct Spacers that are designed and manufactured to your exact specifications are available. We also offer Low EMF (Electro Magnetic Field) Wunpeece Duct Spacers, originally designed for the Los Angeles Department of Water and Power. For all types of duct in many duct bank configurations Engineered for efficiency, RED-E-DUCT consists of UL rated PVC conduits encased in high strength, thermal efficient concrete.5.5 Exceptions to concrete encased ductbanks, i.e. Designed for use in concrete encased duct banks For reinforced concrete ductbank standards refer to NSTAR Construction Standard, C1101, Distribution Duct bank Construction, and (Steel Reinforced Concrete).Easy snap-in design halves labour needed.Custom Spacer Units assembled at no additional cost.Call us at one of our offices or send us a message for more information! Wunpeece Duct Spacer Power Plant Supply Company is pleased to offer you their high quality products. Since its start in 1973, Underground Devices has been a leader in the design and production of duct spacers. The duct spacer is used for underground encasement of conduit/nonmetallic cable racking for use in power and communications manholes. Underground Devices manufactures duct spacers and conduit supports.

Concrete encased duct bank