Solved by hand · NEC 314.28(A)(1)
How long must a pull box be for a straight pull?
The problem
Conductors 4 AWG and larger run straight through a pull box. The largest raceway entering the box is 3 inch conduit. What is the minimum length of the box?
Grab a pen and paper first
Give it a real try on paper before you watch. That is how it works at PSI. If you get stuck, take a hint. If you go blank, that is fine, press play and it gets walked through with you.
Watch it solved, with you
Every step is written out slowly and explained in plain words, so you always know what just happened. Nobody skips ahead and leaves you behind.
Press play and it gets written out with you, one small step at a time.
Every step gets a plain-words explanation here, so you always know exactly what just happened and why.
Now find out if this pattern would cost you points.
The free 15-minute practice test checks this pattern and the rest of the exam's calculation families, then shows what to study first. No signup, no card.