• California CSLB
C10 Electrical 09/11/2026
Exam
California CSLB C10 Electrical Exam review test
bank with over 400 questions and correct
detailed answers
Insulated grounded conductors, in sizes larger than No. 6 AWG, may be identified by _____.
A-a continuous white or natural gray outer finish
B-three continuous white stripes on a purple outer covering
C-distinctive white markings encircling the conductor at its terminations
D-All the above. –
Correct Answer :The Correct Answer Is D
P 1
, • California CSLB
C10 Electrical 09/11/2026
Exam
NEC Sections 200.6(B) permits grounded conductors to be identified by a white or gray outer finish, or by three
continuous white stripes along their entire length on other than green insulation. However, only sizes larger than
No. 6 AWG are permitted to be marked as white or grey at points of termination and such markings must
encircle the entire conductor.
The minimum size copper equipment grounding conductor for a 200-ampere circuit is _____.
A-No. 3 AWG
B-No. 6 AWG
C-No. 8 AWG
D-No. 10 AWG –
Correct Answer :The Correct Answer Is B
NEC Table 250.122 gives No. 6 AWG copper wire as the minimum size for a 200-ampere circuit.
Auxiliary gutters must not be filled to greater than _____.
A-20 percent
B-30 percent
C-40 percent
D-50 percent –
Correct Answer :The Correct Answer Is A
NEC Section 366.6(A) requires that the sum of the cross-sectional areas of all contained conductors at any cross
section of an auxiliary gutter shall not exceed 20 percent of the interior cross-sectional area of the auxiliary
gutter.
The working clearance between live parts for a system operating at 480 volts with exposed live parts on one
side and grounded parts on the other side is _____.
A-1 foot
P 2
, • California CSLB
C10 Electrical 09/11/2026
Exam
B-2 feet
C-3-1/2 feet
D-4 feet –
Correct Answer :The Correct Answer Is C
NEC Table 110.26(A) lists this situation as condition 2 and specifies a minimum of 3-1/2 feet clearance.
A 200-ampere lighting and appliance branch-circuit panelboard may be protected by two main breakers with a
combined rating of _____.
A-150 amperes
B-175 amperes
C-200 amperes
D-225 amperes - Correct Answer :The Correct Answer Is C
The combined overcurrent protection must not exceed the rating of the panelboard.
Panelboards equipped with 30-ampere or less snap switches must be protected not in excess of _____.
A-100 amperes
B-150 amperes
C-200 amperes
D-225 amperes –
Correct Answer :The Correct Answer Is C
The maximum rating of panelboards containing snap switches with ratings of 30 amperes or less is 200 amperes
according to NEC Section 408.16(C).
Panelboards installed in health care facilities and serving the same individual patient vicinity must be bonded
together with copper conductors not smaller than _____.
P 3
, • California CSLB
C10 Electrical 09/11/2026
Exam
A-No. 12 AWG
B-No. 10 AWG
C-No. 8 AWG
D-No. 6 AWG - Correct Answer :The Correct Answer Is B
The equipment grounding terminal busses of branch-circuit panelboards, serving the same individual patient
vicinity, shall be bonded together with an insulated continuous copper conductor not smaller than No. 10 AWG.
The panels of switchboards must be made of _____.
A-moisture-resistant, noncombustible material
B-raintight material
C-impact-resistant material
D-waterproof material - Correct Answer :The Correct Answer Is A
All panels of switchboards must be moisture resistant and composed of non-combustible material. If the panel is
used in other than conventional atmospheres, the housing must be modified to suit the condition. NEC Section
408.30
How shall busbars be mounted in a panelboard?
A-Snug, but not tight.
B-Loose
C-Rigidly
D-Horizontal to the floor. - Correct Answer :The Correct Answer Is C
Insulated or bare busbars shall be rigidly mounted.
The maximum rating of overcurrent devices protecting panelboard instrument circuits is _____.
A-10 amperes
B-20 amperes
C-15 amperes
P 4
C10 Electrical 09/11/2026
Exam
California CSLB C10 Electrical Exam review test
bank with over 400 questions and correct
detailed answers
Insulated grounded conductors, in sizes larger than No. 6 AWG, may be identified by _____.
A-a continuous white or natural gray outer finish
B-three continuous white stripes on a purple outer covering
C-distinctive white markings encircling the conductor at its terminations
D-All the above. –
Correct Answer :The Correct Answer Is D
P 1
, • California CSLB
C10 Electrical 09/11/2026
Exam
NEC Sections 200.6(B) permits grounded conductors to be identified by a white or gray outer finish, or by three
continuous white stripes along their entire length on other than green insulation. However, only sizes larger than
No. 6 AWG are permitted to be marked as white or grey at points of termination and such markings must
encircle the entire conductor.
The minimum size copper equipment grounding conductor for a 200-ampere circuit is _____.
A-No. 3 AWG
B-No. 6 AWG
C-No. 8 AWG
D-No. 10 AWG –
Correct Answer :The Correct Answer Is B
NEC Table 250.122 gives No. 6 AWG copper wire as the minimum size for a 200-ampere circuit.
Auxiliary gutters must not be filled to greater than _____.
A-20 percent
B-30 percent
C-40 percent
D-50 percent –
Correct Answer :The Correct Answer Is A
NEC Section 366.6(A) requires that the sum of the cross-sectional areas of all contained conductors at any cross
section of an auxiliary gutter shall not exceed 20 percent of the interior cross-sectional area of the auxiliary
gutter.
The working clearance between live parts for a system operating at 480 volts with exposed live parts on one
side and grounded parts on the other side is _____.
A-1 foot
P 2
, • California CSLB
C10 Electrical 09/11/2026
Exam
B-2 feet
C-3-1/2 feet
D-4 feet –
Correct Answer :The Correct Answer Is C
NEC Table 110.26(A) lists this situation as condition 2 and specifies a minimum of 3-1/2 feet clearance.
A 200-ampere lighting and appliance branch-circuit panelboard may be protected by two main breakers with a
combined rating of _____.
A-150 amperes
B-175 amperes
C-200 amperes
D-225 amperes - Correct Answer :The Correct Answer Is C
The combined overcurrent protection must not exceed the rating of the panelboard.
Panelboards equipped with 30-ampere or less snap switches must be protected not in excess of _____.
A-100 amperes
B-150 amperes
C-200 amperes
D-225 amperes –
Correct Answer :The Correct Answer Is C
The maximum rating of panelboards containing snap switches with ratings of 30 amperes or less is 200 amperes
according to NEC Section 408.16(C).
Panelboards installed in health care facilities and serving the same individual patient vicinity must be bonded
together with copper conductors not smaller than _____.
P 3
, • California CSLB
C10 Electrical 09/11/2026
Exam
A-No. 12 AWG
B-No. 10 AWG
C-No. 8 AWG
D-No. 6 AWG - Correct Answer :The Correct Answer Is B
The equipment grounding terminal busses of branch-circuit panelboards, serving the same individual patient
vicinity, shall be bonded together with an insulated continuous copper conductor not smaller than No. 10 AWG.
The panels of switchboards must be made of _____.
A-moisture-resistant, noncombustible material
B-raintight material
C-impact-resistant material
D-waterproof material - Correct Answer :The Correct Answer Is A
All panels of switchboards must be moisture resistant and composed of non-combustible material. If the panel is
used in other than conventional atmospheres, the housing must be modified to suit the condition. NEC Section
408.30
How shall busbars be mounted in a panelboard?
A-Snug, but not tight.
B-Loose
C-Rigidly
D-Horizontal to the floor. - Correct Answer :The Correct Answer Is C
Insulated or bare busbars shall be rigidly mounted.
The maximum rating of overcurrent devices protecting panelboard instrument circuits is _____.
A-10 amperes
B-20 amperes
C-15 amperes
P 4
