1
Level 1 and 2 NCCER |Electrical Module 5
(NEC) Quizzes| VERIFIED| 2025/2026
Certification
What happens if a junction box doesn’t have enough space for all the wires and devices inside?
It can lead to overheating or short circuits because the wires are crammed and can’t dissipate
heat properly. NEC has box fill rules for a reason—too many wires in a tight space is asking for
trouble.
When a 14 AWG conductor is protected by a 30A breaker, what NEC rule is being broken?
You’re going over the ampacity limit. NEC says 14 AWG copper can only handle 15 amps
max, so using a 30A breaker means the wire could melt before the breaker trips.
A bathroom outlet is installed without GFCI protection. What’s the problem?
That’s a violation. NEC requires GFCI in all bathrooms because of the moisture risk. No
GFCI means no shock protection near water—super unsafe.
Why would using a metal box without grounding it be flagged during inspection?
Metal boxes can become live if a hot wire touches them. If there’s no ground path, the fault
current won’t trip the breaker, and someone could get shocked touching the box.
In a house, lights flicker every time a big appliance turns on. What NEC rule might’ve been
ignored?
, 2
Probably poor voltage drop planning. NEC recommends no more than 3% drop on branch
circuits. If wire’s too small or run’s too long, big loads cause voltage dips that make lights
flicker.
What could go wrong if someone splices conductors outside a box?
That’s not allowed. NEC says all splices must be inside approved boxes with covers.
Exposed splices can get damaged or cause fires.
An outdoor receptacle was installed with no in-use cover. What’s the NEC issue here?
NEC says outdoor outlets need weatherproof covers, even when something’s plugged in. No
in-use cover = rainwater in the plug = shock hazard.
During rough-in, a guy staples NM cable too tight. What rule does that break?
You’re not supposed to damage the insulation. NEC says you have to secure cables without
compressing or crushing them, or they could overheat.
Why’s it wrong to run low-voltage data cables in the same conduit as power wires?
NEC separates power and communication wiring to avoid interference. You’d mess up signal
quality, plus it’s just not code-compliant.
What’s the danger if a panel neutral and ground are bonded in a subpanel?
That’s a big no-no. Only the main panel should bond neutral and ground. Doing it in a
subpanel can send return current through ground paths, which is dangerous.
Level 1 and 2 NCCER |Electrical Module 5
(NEC) Quizzes| VERIFIED| 2025/2026
Certification
What happens if a junction box doesn’t have enough space for all the wires and devices inside?
It can lead to overheating or short circuits because the wires are crammed and can’t dissipate
heat properly. NEC has box fill rules for a reason—too many wires in a tight space is asking for
trouble.
When a 14 AWG conductor is protected by a 30A breaker, what NEC rule is being broken?
You’re going over the ampacity limit. NEC says 14 AWG copper can only handle 15 amps
max, so using a 30A breaker means the wire could melt before the breaker trips.
A bathroom outlet is installed without GFCI protection. What’s the problem?
That’s a violation. NEC requires GFCI in all bathrooms because of the moisture risk. No
GFCI means no shock protection near water—super unsafe.
Why would using a metal box without grounding it be flagged during inspection?
Metal boxes can become live if a hot wire touches them. If there’s no ground path, the fault
current won’t trip the breaker, and someone could get shocked touching the box.
In a house, lights flicker every time a big appliance turns on. What NEC rule might’ve been
ignored?
, 2
Probably poor voltage drop planning. NEC recommends no more than 3% drop on branch
circuits. If wire’s too small or run’s too long, big loads cause voltage dips that make lights
flicker.
What could go wrong if someone splices conductors outside a box?
That’s not allowed. NEC says all splices must be inside approved boxes with covers.
Exposed splices can get damaged or cause fires.
An outdoor receptacle was installed with no in-use cover. What’s the NEC issue here?
NEC says outdoor outlets need weatherproof covers, even when something’s plugged in. No
in-use cover = rainwater in the plug = shock hazard.
During rough-in, a guy staples NM cable too tight. What rule does that break?
You’re not supposed to damage the insulation. NEC says you have to secure cables without
compressing or crushing them, or they could overheat.
Why’s it wrong to run low-voltage data cables in the same conduit as power wires?
NEC separates power and communication wiring to avoid interference. You’d mess up signal
quality, plus it’s just not code-compliant.
What’s the danger if a panel neutral and ground are bonded in a subpanel?
That’s a big no-no. Only the main panel should bond neutral and ground. Doing it in a
subpanel can send return current through ground paths, which is dangerous.
