NEC Commercial Electrical Test 1
Questions and Answers | Latest Version
| 2024/2025 | Correct & Verified
What is the required minimum clearance in front of electrical equipment rated 480V in a
commercial setting?
✔✔3 feet
What is the maximum number of current-carrying conductors allowed in a single raceway before
derating is required?
✔✔3
What is the minimum size equipment grounding conductor for a 200-amp feeder circuit?
✔✔6 AWG
What is the maximum allowable load on a 20-amp commercial branch circuit for continuous
use?
✔✔16 amps
1
,What is the required voltage rating for commercial fluorescent lighting circuits?
✔✔277 volts
What is the minimum height for mounting a disconnect switch in a commercial application?
✔✔6 feet 7 inches
What is the required ampacity of conductors feeding a 30-amp three-phase motor in a
commercial setting?
✔✔30 amps
What is the minimum burial depth for rigid PVC conduit in a commercial parking lot?
✔✔24 inches
What type of receptacle is required in commercial kitchens near sinks or wet areas?
✔✔GFCI
What is the required interval for supporting flexible metal conduit (FMC) in a commercial
installation?
2
,✔✔4.5 feet
What is the maximum allowable length of flexible metal conduit for connecting equipment
subject to vibration?
✔✔6 feet
What is the minimum size bonding jumper required for a 100-amp commercial service?
✔✔8 AWG
What is the required separation between parallel conduits carrying high-voltage and low-voltage
conductors in commercial applications?
✔✔12 inches
What is the maximum allowable voltage drop for a feeder circuit in a commercial building?
✔✔3%
What is the minimum required space above a suspended ceiling for installing junction boxes?
✔✔3 inches
3
, What is the ampacity of a 10 AWG copper conductor at 90°C in a commercial application?
✔✔40 amps
What is the minimum clearance from combustible materials for surface-mounted lighting
fixtures in a commercial setting?
✔✔6 inches
What is the required minimum spacing between metal conduit and combustible materials?
✔✔1 inch
What is the maximum length of a cord used for portable appliances in a commercial kitchen?
✔✔6 feet
What is the minimum depth required for burying EMT under a commercial driveway?
✔✔18 inches
4
Questions and Answers | Latest Version
| 2024/2025 | Correct & Verified
What is the required minimum clearance in front of electrical equipment rated 480V in a
commercial setting?
✔✔3 feet
What is the maximum number of current-carrying conductors allowed in a single raceway before
derating is required?
✔✔3
What is the minimum size equipment grounding conductor for a 200-amp feeder circuit?
✔✔6 AWG
What is the maximum allowable load on a 20-amp commercial branch circuit for continuous
use?
✔✔16 amps
1
,What is the required voltage rating for commercial fluorescent lighting circuits?
✔✔277 volts
What is the minimum height for mounting a disconnect switch in a commercial application?
✔✔6 feet 7 inches
What is the required ampacity of conductors feeding a 30-amp three-phase motor in a
commercial setting?
✔✔30 amps
What is the minimum burial depth for rigid PVC conduit in a commercial parking lot?
✔✔24 inches
What type of receptacle is required in commercial kitchens near sinks or wet areas?
✔✔GFCI
What is the required interval for supporting flexible metal conduit (FMC) in a commercial
installation?
2
,✔✔4.5 feet
What is the maximum allowable length of flexible metal conduit for connecting equipment
subject to vibration?
✔✔6 feet
What is the minimum size bonding jumper required for a 100-amp commercial service?
✔✔8 AWG
What is the required separation between parallel conduits carrying high-voltage and low-voltage
conductors in commercial applications?
✔✔12 inches
What is the maximum allowable voltage drop for a feeder circuit in a commercial building?
✔✔3%
What is the minimum required space above a suspended ceiling for installing junction boxes?
✔✔3 inches
3
, What is the ampacity of a 10 AWG copper conductor at 90°C in a commercial application?
✔✔40 amps
What is the minimum clearance from combustible materials for surface-mounted lighting
fixtures in a commercial setting?
✔✔6 inches
What is the required minimum spacing between metal conduit and combustible materials?
✔✔1 inch
What is the maximum length of a cord used for portable appliances in a commercial kitchen?
✔✔6 feet
What is the minimum depth required for burying EMT under a commercial driveway?
✔✔18 inches
4
