Raceway Basics
What is a raceway used for in electrical systems?
A channel to run wire and to provide protection for that wire.
What tool is used to bend EMT?
Hand bender, auto bender.
What is the most common size EMT used in residential work?
1/2"
What color is electrical PVC?
Gray.
What does RMC stand for?
Rigid Metal Conduit.
Name one example of a raceway.
EMT, RMC, PVC
Can EMT be threaded?
No
What is the maximum number of bends allowed in EMT between pull points?
360 degrees.
Can you use white plumbing PVC for electrical installations?
No.
What is RMC typically made from?
Galvanized or stainless steel.
Is IMC thicker or thinner than RMC?
Thinner
What is EMT conduit made of?
Galvanized steel and aluminum.
What must be done to avoid damaging conductors when pulled through a raceway?
Ream or deburr the pipe.
What does PVC stand for?
Polyvinyl Chloride.
Where would RMC be a better choice than EMT or PVC?
Near the floor of an industrial facility.
What is the star on a hand bender used for?
The second bend in a back-to back 90
What NEC article covers EMT?
Article 358
What is the take up for a 90 degree bend with 3/4" EMT?
6"
What NEC article covers PVC conduit?
Article 352.
What NEC article governs the installation of RMC, and what key rule does it state about thread protection?
Article 344; threads must be protected from corrosion by paint tape or compound.
What is the difference between a raceway and a cable like Romex?
A raceway is a continuous enclosed pathway for wires. Romex is a cable assembly.
What should NEVER be done with galvanized metal and why?
Welding. At high temperatures, the zinc coating vaporizes and puts off toxic fumes.
What is the take up for a 90 degree bend using 1/2" EMT?
5"
What is one advantage of using PVC over metal conduit?
It is lightweight, non-corrosive, and easy to cut.
Why is RMC permitted to serve as an equipment grounding conductor, and what NEC condition must be met for that to be allowed?
Because it is a metal pipe and thus conductive. NEC 250.118 states that all couplings and fittings must ensure a reliable and conductive path.