Conduit Raceways & Commercial Projects

• 6 ft whip pre wired with 3/8 in. flex

concealed cover plaster ring

NEC Code/Your Authority will not allow NMB and other styles of romex wiring to be installed in commercial buildings above certain floor levels or not at all. To find the code in your area check with the zoning and permit section of your local authority for their rules and regulations. Mostly only emt, imc, rigid conduit and BX metal flexible for whips up to 6' for light fixtures/troffers into drop ceilings. As well as other materials rated for commercial use are allowed.

surfaced mounted cover

 Custom bending of these conduit raceways can be surface mounted or concealed inside walls and ceilings. No more than 4-90 degree turns can be made from start to end of any race way and many other rules apply concerning conduit raceway systems for commercial inspection concerning NEC Code/Your Authority. If the distance takes more than 4-90 degree turns then pull boxes are needed, but once again you can only make 4 turns before another pull box is needed.

example http://www.westernextralite.com/conduit-fill-table

Then there are fill charts of how many and types of wires that can be installed within each conduit raceway. In short the rules are very different from Residential to Commercial projects. After you think that you have all that figured out there are derating factors to consider also. Properly installed these conduit raceways are grounded thru grounding rod or rods meaning that if an energized wire touches the conduit it is designed to trip the circuit breaker protecting the wire. With the many different styles of conduit and uses for them it is usually better to leave these projects to the Pros.

Here at D B Electric when we bid/quote commercial projects many hours of research goes into reading the Blueprints, meetings with engineers on specifications and any other issue before the job even is submitted for Client approval.

So how does a person learn to make the bends and bending of these conduit systems? Trade schools, community colleges, apprenticeship programs with unions and electrical contractors are the usual methods to learn the tricks of the trade. In short there is nothing easy about conduit systems they are a complex jigsaw puzzle of many different items aka boxes, fittings, conduit straps, and many other items to have a quality finished craftsmanship project.

All that just skims the surface about emt/imc/rigid conduit systems as now we can add yet another raceway systems called PVC conduit used for direct burial into the ground and above ground applications for commercial and residential use. The same 4-90 degree turns apply and the same NEC/Your Authority apply to PVC conduit raceway systems and are even listed separately in the NEC code book. (NOTE) you can not bury emt conduit directly into the earth it is not rated for the use and will quickly deteriorate and rust out where as PVC is rated for the purpose as well as rigid conduit raceway systems.

Wiremold metallic raceways that are surface mounted to walls and ceilings usually used for applications where the commercial building has already been built and the cost to rip open the walls offset the cost of a fast surface mounted raceway system. Many different styles along with metallic and nonmetallic options are available. The same 4-90 degree turns apply as with other NEC/Your Authority codes and rules. 

So as you can see commercial conduit raceway systems are complicated and take not only the electricians but also engineers, blueprint designers and many other teams of people and their staffs. This only touches the surface on conduit raceway systems there are many more materials not mentioned or described. Numbers never lie concerning electrical applications that even means in conduit raceway system. To make a 90-degree turn in 1/2" emt takes 5" each and every time.

D B Electric

email www.offgridpowerdbelectric@gmail.com