What's on the Chicago Low Voltage Supervising Electrician Exam?

What's on the Chicago Low Voltage Supervising Electrician Exam?

The Chicago Supervising Low Voltage Electrician exam has 100 four-option questions in 3 hours, on paper, and you need 70. Continental Testing Services (CTS) publishes the outline in its study guide. It has the same two parts as the General exam, with fewer questions: 25 on electrical principles and practices and 75 on the Chicago Electrical Code.

The low voltage license only covers Class 1, 2 and 3 circuits and communications work, but the exam does not stay inside Articles 725 to 840. Every NEC chapter is on it.

Part I: Electrical Principles and Practices (25 questions)

This part is identical to the General exam's. CTS names the American Electrician's Handbook (16th edition) and 29 CFR 1926 as references, but neither is allowed in the exam room, so you answer from what you know and from the calculator: Ohm's law, power and power factor, delta and wye relationships, transformer current and voltage drop. The OSHA questions come from the construction standard, especially Subpart K on electrical safety.

Part II: Chicago Electrical Code (75 questions)

Wiring methods is the largest code area, and communication systems is as large as wiring and protection. The low-voltage articles sit in three of these areas: audio, information technology and similar equipment (640, 645, 650) in the 600s; Class 1, 2 and 3 circuits, fire alarm systems and optical fiber (725, 760, 770) in the 700s; and communications, radio and TV, CATV and network-powered broadband (800 to 840) in the 800s. Our full-length practice exam uses the middle of each range, with the 200s, 400s and 500s at the low end of theirs so the code part totals 75.

Chicago's low-voltage rules

The 2018 Chicago Electrical Code is the 2017 NEC with Chicago's changes in Title 14E of the Municipal Code, in force since March 1, 2018. Several of those changes land squarely on low-voltage work:

• Plenums. Nationally, plenum-rated cable (CL2P, CL3P, FPLP, OFNP, CMP) can be run in other spaces used for environmental air. In Chicago, Class 2 and 3, fire alarm, optical fiber and communications cables in plenums must be installed by the wiring methods of 300.22(C) (725.135, 760.135, 770.113, 800.113).
• Fire alarm systems. Chicago adds its own sections for required fire alarm and emergency voice systems. The primary power comes from the Article 700 emergency system, on circuits identified "FIRE ALARM CIRCUIT" (760.184). The control equipment goes in a dedicated one-hour fire-rated room, never below grade (760.185). Conductors are 16 AWG minimum (18 AWG only in a multiconductor cable), with no more than 5% voltage drop on secondary power (760.183).
• Off-premises connections. The connection to a municipal fire alarm box runs in metal conduit, at least 2 in., buried 24 in. outside, with five 14 AWG or larger conductors of different colors (760.210).
• Information technology rooms. Branch circuits under a raised floor must be in metal raceways (645.5(E)); the national list also allows nonmetallic raceways and cable assemblies.
• Articles Chicago drops. Chicago does not adopt Article 728 (fire-resistive cable systems), and it replaces NEC Article 700 with its own emergency systems article built around System I, II and III emergency lighting.

When a question turns on one of these rules, the national answer is wrong in Chicago. Tab Articles 725, 760, 770 and 800, and mark where Title 14E rewrites them.

City law: Titles 2, 4 and 13

The 5 to 7 city-law questions come from a CTS handout, "Selected Provisions of Titles 2, 4 and 13," which CTS gives every candidate at the exam and lets you download to study. It covers the Department of Buildings, electrical contractor and supervising electrician licensing (Chapters 4-290 and 4-292), and old Title 13 on electrical permits and inspections, wires on the public way and fines. The handout reflects the code as of December 13, 2017, before the administrative rules moved to Title 14A, so study the handout rather than current Title 14A.

How to study

1. Tab the 2018 Chicago Electrical Code by article, with extra tabs at 725, 760, 770, 800, 820 and 830 and at the Chicago fire alarm sections. Notes and highlighting are not allowed in the exam book; tabs are.
2. Do not skip the power chapters. More than 40 of the 75 code questions come from Chapters 1 to 5.
3. Read the Titles 2, 4 and 13 handout once through. The same copy is in front of you during the exam.
4. Drill the principles part with a calculator, and practice pace: 100 questions in 3 hours is 1.8 minutes each.

Start with our free, untimed Chicago Low Voltage Supervising Electrician sample test. Every question cites the 2017 NEC, Title 14E, Municipal Code or OSHA section it comes from. With a subscription you can also take full-length practice exams in Timed Exam mode. For eligibility, fees and exam dates, see the requirements.