SUBSTATION ELECTRICIAN APPRENTICESHIP EXAM QUESTIONS
AND CORRECT ANSWERS LATEST UPDATE!!!! ALREADY GRADED
A+
Please list the 6 major categories of discussion for any tailboard. - (ANSWER)a. Methods of emergency
notification
b. What is our job plan?
c. What is energized? What is not? What are the clearance points?
d. What are the hazards associated with the job?
e. What are the assignments, groups or individuals?
Special precautions, special equipment, PPE?
g. Does everyone understand/ask questions?
What are the major categories of a Substation Maintenance switching tailboard? - (ANSWER)a. Methods
of emergency notifications
b. What is our switching assignment?
c. How will we accomplish the switching?
d. Have I verified equipment to be operational?
e. What are the hazards involved/ PPE required?
f. What are my clearance points?
g. Are grounds installed? If so, where?
What are the basic safe work practices observed in a 230KV or 500KV receiving station? -
(ANSWER)Check in to station upon arrival, close and lock gate after entering. Maintain MAD for
personnel and equipment as well as safe working clearances at all times 500KV- PTG 11'11"PTP
19'9"230KV- PTG 5'8"PTP 9'2"115KV- PTG 3'4" PTP 4'7" 69KV- PTG 2'11" PTP 3'9" PWalk down yard and
visually inspect for damaged equipment or missing/broken grounds.tailboard with other crews in
working in the same area. Maintain speed limits and follow roadways.
What insulating mediums are used in EHV breakers? - (ANSWER)SF6 gas, ultra-dry high pressure air,
polymer, ceramics, air, epoxy, silicone
What does a WIKA gauge measure? - (ANSWER)WIKA is a brand. Usually, it is measuring gas pressure.
, SUBSTATION ELECTRICIAN APPRENTICESHIP EXAM QUESTIONS
AND CORRECT ANSWERS LATEST UPDATE!!!! ALREADY GRADED
A+
What is the minimum % of gas density that SRP allows in an EHV breaker? - (ANSWER)98% on all new
breakers,98% on Palo Verde Breakers, 97% on all other voltage class breakers including older 500KV
breakers.
Is SF6 gas harmful and or a hazardous material? - (ANSWER)Yes, it displaces oxygen and can create a
toxic substance when used to suppress an electric arc. It is invisible, odorless, and tasteless.
Explain the difference between a live tank and a dead tank breaker. - (ANSWER)A live Tank breaker has
external energized tanks that are isolated from ground. These tanks contain the interrupting contacts,
which are above ground potential.
A dead tank breaker has their interrupting contacts enclosed in tanks that are at ground potential.
What type of EHV breaker has a free standing C.T.? - (ANSWER)A live tank breaker.
Preventative breaker maintenance consists of what? - (ANSWER)Tailboard and be working under a
grounded clearance. Power factor test, ductor/micro-ohm test (the resistance of closed contacts, timing
test ( opening and closing) , checking moisture, purity and density of SF6 gas (and content of SO2 if any),
pressure switch settings, service the compressors (oil change and belt checks, pump times), check
heaters, mechanism travel measurements, alarm checks ( low gas and low gas lock outs, motor
trouble/fail) , and an inspection of the overall condition of the breaker.
Name the different types of operating mechanisms and explain the safety hazards associated with each. -
(ANSWER)Air Hazards include: pressurized containment vessel, air leaks are not visible, fittings, hoses,
regulators and air tools need to be rated for the pressure to be applied, beware of moving parts, drain air
pressure before performing maintenance.
Hydraulic hazards: pressurized containment vessel, containment vessel has a nitrogen pre-charge
pressure even after hydraulic pressure has been drained, hydraulic oil is flammable, beware of moving
parts, drain hydraulic pressure before performing maintenance.
AND CORRECT ANSWERS LATEST UPDATE!!!! ALREADY GRADED
A+
Please list the 6 major categories of discussion for any tailboard. - (ANSWER)a. Methods of emergency
notification
b. What is our job plan?
c. What is energized? What is not? What are the clearance points?
d. What are the hazards associated with the job?
e. What are the assignments, groups or individuals?
Special precautions, special equipment, PPE?
g. Does everyone understand/ask questions?
What are the major categories of a Substation Maintenance switching tailboard? - (ANSWER)a. Methods
of emergency notifications
b. What is our switching assignment?
c. How will we accomplish the switching?
d. Have I verified equipment to be operational?
e. What are the hazards involved/ PPE required?
f. What are my clearance points?
g. Are grounds installed? If so, where?
What are the basic safe work practices observed in a 230KV or 500KV receiving station? -
(ANSWER)Check in to station upon arrival, close and lock gate after entering. Maintain MAD for
personnel and equipment as well as safe working clearances at all times 500KV- PTG 11'11"PTP
19'9"230KV- PTG 5'8"PTP 9'2"115KV- PTG 3'4" PTP 4'7" 69KV- PTG 2'11" PTP 3'9" PWalk down yard and
visually inspect for damaged equipment or missing/broken grounds.tailboard with other crews in
working in the same area. Maintain speed limits and follow roadways.
What insulating mediums are used in EHV breakers? - (ANSWER)SF6 gas, ultra-dry high pressure air,
polymer, ceramics, air, epoxy, silicone
What does a WIKA gauge measure? - (ANSWER)WIKA is a brand. Usually, it is measuring gas pressure.
, SUBSTATION ELECTRICIAN APPRENTICESHIP EXAM QUESTIONS
AND CORRECT ANSWERS LATEST UPDATE!!!! ALREADY GRADED
A+
What is the minimum % of gas density that SRP allows in an EHV breaker? - (ANSWER)98% on all new
breakers,98% on Palo Verde Breakers, 97% on all other voltage class breakers including older 500KV
breakers.
Is SF6 gas harmful and or a hazardous material? - (ANSWER)Yes, it displaces oxygen and can create a
toxic substance when used to suppress an electric arc. It is invisible, odorless, and tasteless.
Explain the difference between a live tank and a dead tank breaker. - (ANSWER)A live Tank breaker has
external energized tanks that are isolated from ground. These tanks contain the interrupting contacts,
which are above ground potential.
A dead tank breaker has their interrupting contacts enclosed in tanks that are at ground potential.
What type of EHV breaker has a free standing C.T.? - (ANSWER)A live tank breaker.
Preventative breaker maintenance consists of what? - (ANSWER)Tailboard and be working under a
grounded clearance. Power factor test, ductor/micro-ohm test (the resistance of closed contacts, timing
test ( opening and closing) , checking moisture, purity and density of SF6 gas (and content of SO2 if any),
pressure switch settings, service the compressors (oil change and belt checks, pump times), check
heaters, mechanism travel measurements, alarm checks ( low gas and low gas lock outs, motor
trouble/fail) , and an inspection of the overall condition of the breaker.
Name the different types of operating mechanisms and explain the safety hazards associated with each. -
(ANSWER)Air Hazards include: pressurized containment vessel, air leaks are not visible, fittings, hoses,
regulators and air tools need to be rated for the pressure to be applied, beware of moving parts, drain air
pressure before performing maintenance.
Hydraulic hazards: pressurized containment vessel, containment vessel has a nitrogen pre-charge
pressure even after hydraulic pressure has been drained, hydraulic oil is flammable, beware of moving
parts, drain hydraulic pressure before performing maintenance.
