CPI Installation Techniques & Procedures 4

Question 1

When splicing two sections of load-bearing unistrut channel, what is required to maintain structural integrity?

Accepted Answer

Use a listed splice plate or fitting with proper fasteners torqued to specification

Answer

Listed splice plates engineered for strut channel distribute load across the joint and maintain the rated load capacity of the assembly.

Question 2

A customer reports a newly installed shelf is level when empty but sags under load. What is the most likely cause?

Accepted Answer

Bracket spacing is too wide for the shelf material and load

Answer

Insufficient bracket spacing relative to shelf material thickness and expected load causes deflection; adding intermediate brackets resolves the issue.

Question 3

What is the purpose of leaving a 1/8-inch expansion gap between butted panels during installation?

Accepted Answer

To accommodate thermal expansion and prevent buckling or warping

Answer

All materials expand and contract with temperature changes; gap spacing prevents panels from pushing against each other and buckling.

Question 4

When running exposed EMT conduit outdoors, which installation requirement must be met at each connection?

Accepted Answer

Use raintight (weatherproof) fittings rated for wet locations

Answer

Wet location-rated raintight fittings are required by the NEC for outdoor EMT runs to prevent moisture entry and corrosion.

Question 5

What is the most effective technique for pulling wire through a long conduit run with multiple bends?

Accepted Answer

Apply listed wire-pulling lubricant and use a fish tape or pull string with a pull grip

Answer

Pull lubricant reduces friction at bends while a fish tape and pull grip distribute pulling force to prevent insulation damage on long runs.

(CPI) Certified Professional Installer Practice Test

(CPI) Certified Professional Installer Practice Test

CPI Installation Techniques & Procedures 4