How To Answer A Box Fill Question For The PSI Exam

How to answer a box fill (w/ grounding conductor) question for the Journeyman electrician and Master electrician Texas PSI exam.

This is a box fill question. Helpful to make a chart.

Given (2) number 8 ungrounded conductors, (2) number 8 grounded conductors, (2) #10 ungrounded conductors, (2) #10 grounded conductors, (4) #12 equipment grounding conductors, and (2) cable clamps, calculate the minimum cubic area needed for these conductors?

Remember grounded conductors= an intentional grounded conductor.

#8- 5 count-each@3.00 cu in
#10- 4 count- each @ 2.50 cu in
#12- 1 count @ 2.25 cu in

15+ 10+ 2.25= 27.25

The answer is 28 cubic inches (don’t forget to round up)

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