ICC Electrical Systems and Safety 2 — Questions and Answers
Question 1: In Illinois, what is the maximum voltage permitted for temporary wiring used during construction?
- 120V
- 240V
- 600V (Correct answer)
- There is no maximum for temporary wiring
Correct answer: 600V
Temporary wiring used during construction is permitted up to 600 volts under NEC guidelines adopted in Illinois.
Question 2: Which type of conduit is required in areas exposed to physical damage in Illinois commercial buildings?
- PVC Schedule 40
- Electrical Metallic Tubing (EMT)
- Flexible metallic conduit
- Rigid Metal Conduit (RMC) (Correct answer)
Correct answer: Rigid Metal Conduit (RMC)
Rigid Metal Conduit (RMC) provides the highest physical protection and is required in areas subject to physical damage.
Question 3: What is the purpose of an equipment grounding conductor in an electrical circuit?
- To carry the neutral return current
- To provide a low-impedance fault path that trips the breaker (Correct answer)
- To increase circuit capacity
- To reduce electricity bills
Correct answer: To provide a low-impedance fault path that trips the breaker
The equipment grounding conductor provides a safe fault return path that causes the overcurrent device to trip quickly during a fault.
Question 4: Before excavating near underground utilities in Illinois, contractors are legally required to call:
- The local fire department
- JULIE (811 — Joint Utility Locating Information for Excavators) (Correct answer)
- OSHA directly
- The property owner's insurance company
Correct answer: JULIE (811 — Joint Utility Locating Information for Excavators)
Illinois law requires contractors to call JULIE (811) at least 48 hours before excavating to have underground utilities marked.
Question 5: What does the term 'bonding' mean in electrical installations?
- Connecting two wires with tape
- Joining metallic parts to ensure electrical continuity and conductivity (Correct answer)
- Installing a second breaker panel
- Coating wires with anti-corrosion spray
Correct answer: Joining metallic parts to ensure electrical continuity and conductivity
Bonding connects all metallic parts of an electrical system together to prevent dangerous voltage differences between them.
Question 6: Arc Fault Circuit Interrupters (AFCIs) are required in Illinois residential bedrooms to protect against:
- Overloads only
- Electrical fires caused by arcing faults in wiring (Correct answer)
- Power surges from the utility
- Voltage drops in the circuit
Correct answer: Electrical fires caused by arcing faults in wiring
AFCIs detect dangerous arcing conditions in wiring that standard breakers cannot detect and shut off power to prevent fires.
ICC Electrical Systems and Safety 2
In Illinois, what is the maximum voltage permitted for temporary wiring used during construction?