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Self Study Questions > 2nd Step > Flashcards

2nd Step Flashcards

1
Q

According to the APM, what size and type of rope is required for lowering a person
from a pole?

A

Rope with a safe workload rating equal to approved 1/2 inch hand line material shall be used when lowering a person from a pole or elevated position.
Reference: APM Rule 1022.a.3

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2
Q

What information is required on a cable tag?

A

4.1 Primary Cables
Primary cables shall be tagged at every piece of equipment and as it enters or leaves a structure in such a manner that the tag is visible and the location is accessible to the worker.
Each cable tag shall include the following information:
A. Adjacent sectionalizing device position
B. Adjacent sectionalizing device number
C. Adjacent sectionalizing structure number
D. Next adjacent structure number (through structure)
E. Footage to next adjacent structure or piece of equipment in same structure
F. Direction to next adjacent structure or piece of equipment in same structure
G. Operating voltage (4kv, 12kv, 6.9 kv)
reference DUG IC 140.4.1

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3
Q

How does a lineman find the fault duty for a particular circuit?

A

Obtain fault-current duty of the system from the Protection Engineering website. If multiplesources can inadvertently energize the line, select the appropriate size of grounds that will provide protection for the highest available fault duty at each grounding location.Reference: Overhead Grounding Manual, 2.3.2

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3
Q

What is the purpose of a breakaway reel?

A

This reel is designed to recover overhead, as well as underground, conductors that are to be salvaged.
Reference: Rigging Standards Manual, p. 67

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4
Q

What are the maximum fault duties for the three sizes of grounds used on distribution voltages?

A

2 = 9.000 A

2/0 = 18,000 A
4/0 = 30,000 A
Reference: Overhead Grounding Manual, Table 3-1

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5
Q

What size grounds should be used on 1/0 ACSR circuit with a fault duty of 10,000 A?

A

2 because it can be used on 1/0 ACSR or #2 copper regardless of fault duty

2/0 can be used on 4/0 acsr or 2/0 copper
Reference: Overhead Grounding Manual, Table 3-1 Note 1

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6
Q

How often is grounding equipment tested?

A

Every 2 years, through GARP.
Reference: Overhead Grounding Manual, 5.1

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7
Q

Every 2 years, through GARP.
Reference: Overhead Grounding Manual, 5.1

A

Substation Ground Grid as Ground Medium Substation ground grid is the priority ground medium to be used for grounding. When grounding within 40 feet of substation ground grid, the fault current, if the line is inadvertently energized, will be as high as the fault-current duty of the substation bus. Therefore, the substation ground grid shall be used as a ground medium when grounding within 40 feet of the substation ground grid and proper locations shall be selected for routing and attaching grounds to the substation ground grid
Reference: Overhead Grounding Manual, 3.6.2

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8
Q

The APM prescribes two safety guidelines that must be performed prior to working on a transformer with banked secondaries. What are they?

A

Where secondaries of transformers are banked or there is a possibility of a backfeed, the transformer secondary leads shall be disconnected in addition to pulling primary fuses before any work is done on a transformer.
Reference: APM Rule 217.a

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9
Q

What size conductors are typically used in single-phase lighting secondaries?

A

Certain sizes of conductors are most commonly used for lighting secondaries: 1/0 aluminum or #2 copper in all residential areas except those designed for minimum service, and 4/0 aluminum or 2/0 copper where the initial installation requires transformers larger than 25 kVA.
Reference: DOH, 400.1.0

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10
Q

What are the minimum acceptable Megger test values for accepting both new and old transformers, prior to installation?

A

New: >999 M ohms.
New LV to case >500 M ohms
Old: >500 M ohms
Reference: Megger and TR Reference Manual for Testing Distribution Transformers, Megger 4.0
OB-0722

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11
Q

Why are Megger checks performed on transformers?

A

The Megger measures the effectiveness of a transformer’s electrical insulation. This insulation includes materials such as paper, pressboard, phenolic, ceramics, plastics, and oil placed between electrical conductors to prevent electricity from leaking across them.
The Megger applies a high voltage (1,000vdc) across two different electrical components. It then measures the leakage current and displays the resistance of the insulation in units of Mega-Ohms (MΩ). The Megger tests where there should be NO electrical path
High to low
High to case
Low to case
Reference: Megger and TR Reference Manual for Testing Distribution Transformers, Megger 1.0

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12
Q

What is special about Megger and TTR tests on 6.9 kV/9.5 kV (©-Ground) 240/120 V, non-fused, single-phase looped BUD transformers with three low-voltage bushings?

A

No Megger test is possible since both windings and the tank are all connected.
Reference: Megger and TR Reference Manual for Testing Distribution Transformers, Megger and TR Testing of Specific Transformer Types 5.0

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13
Q

List two examples of transformer defects that may be detected with TTR and Megger checks.

A

short across windings in high or low side
short from high coil to case
short from low coil to case
short from high coil to low coil.
open circuit internally
wrong polarity
Each of the defects just described may be detected using the Megger and TTR
Reference: Megger and TR Reference Manual for Testing Distribution Transformers,
Transformer Fundamentals 3.0

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14
Q

What five precautions must be observed before and/or during Megger testing of a
transformer?

A

1.Isolate the Transformer.
2.Watch out for Shocks
3. Make Good Electrical Contact with the Terminals
4. Vent the Transformer
5. Understand the Transformer Nameplate
Reference: Megger and TR Reference Manual for Testing Distribution Transformers,
Megger 2.0

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15
Q

Why are TTR checks performed on distribution transformers, prior to installation?

A

1.0 TTR Performs Three Tests
1. Transformer turns Ratio (TTR) displayed as % error.
2. No continuity will show as Failed TTR Test or Failed Test with a very high ratio or overrange or open circuit.
3. Polarity as related to hookup, displayed as + or - sign on measured ratio line
Reference: Megger and TTR Reference Manual for Testing Distribution Transformers, TTR 4.0

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16
Q

What is the purpose of a transformer tap changer? How does it work?

A

Tap changers allow the transformer to be “fine tuned” so that the output of the transformer remains at the rated low voltage despite a higher- or lower-system voltage. This “fine tuning” is accomplished by increasing or decreasing the effective number of turns in the high-voltage winding.
Reference: Megger and TR Reference Manual for Testing Distribution Transformers,
Tap Changers 1.1

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16
Q

Describe what a transformer’s polarity is.

A

Single-phase transformer nameplates indicate whether its polarity is additive or subtractive. Polarity indicates the relative direction of current flow through the transformer. Polarity is determined by looking at the “polarity bushing” (H1) on the transformer, and its relation to the X1 bushing. When H1 and X1 are on the same side, it is considered subtractive polarity. When H1 and X1 are on opposite sides, it is considered additive polarity. With standard markings, if the direction of current flow is from H1 to H2, the current flow will be in the direction of X2 to X1
Reference: 2nd Step Transformer Theory Training Manual

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17
Q

What is the maximum acceptable level of error (percentage) when performing a TTR check on a transformer?

A

IEEE standards allow manufacturers to build transformers with percentage errors up to 0.5 %. This is the number that the TTR uses to determine whether the transformer being tested passes or fails.
Reference: Megger and TR Reference Manual for Testing Distribution Transformers,
TTR 5.0

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18
Q

Is it permissible to operate a transformer’s tap changer while it is energized or part of a bank?

A

There are two types of tap changers: no load tap changer and load tap changer. No load tap changers require the transformer to be de-energized, so there is a short interruption in customer service while the taps are changed. Load tap changers provide the ability to change taps while the transformer is energized and without interrupting the flow of current through the transformer and to the customer.
Reference: 2nd Step Transformer Theory Training Manual

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19
Q

Concerning pole framing and crossarm construction on a rural pole, when are V braces required?

A

Use V-braces for wire size larger than #2 copper and 1/0 ASCR.
Reference: DOH, Figure DC 500-1 Note 2

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20
Q

Is it permissible to reduce the required 6-foot clearance between secondary
conductors and communications lines? If so, how?

A
  1. Clearance between secondary and communication circuits of existing poles may be reduced from 6 feet to 4 feet with the installation of a guard arm.
    Reference: DOH, Figure DC 200-1 Note 2
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21
Q

What are the ampacities for each of the following conductor types/sizes?

A

4 ACSR - 160

1/0 ACSR - 280
4/0 ACSR - 415
336 ACSR - 605
653 ACSR - 920
#4 AT - 110
#2 AT - 145
1/0 AT - 190
4/0 AT - 300
1/ AQ - 180
4/0 AQ - 275
2nd Step Self-Study Question
Reference: DOH, CO 106

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22
Q

What is the requirement for placing HIGH VOLTAGE signs on wood poles with crossarm(s) supporting the lowest level of the line conductors energized in excess of 750 V?

A

A. Wood Poles — The standard location for marking wood poles with HIGH VOLTAGE signs is on the pole. Use the plastic HIGH VOLTAGE sign (SAP 10135280) with engraved black letters on yellow background and galvanized nails. HIGH VOLTAGE signs are to be placed in order to approximately encircle the pole so that the top of the sign is located no more than 40 inches below the lowest level of the line conductors energized in excess of 750 V.
if you cant put it on the pole, every arm must have high voltage signs.
Reference: DOH. PO 120.2 3.1

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23
Q

What is the WLL of a stabilizer (silver) gin?

A

2000 Ibs
Reference: Rigging Standards Manual, Figure 205

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24
Q

What is a USA, and when would it be required? What company provides SCE with USA service?

A

USA = Underground Service Alert.
USA information is provided to SCE by DigAlert.
State of California Government Code 4216 mandates that anyone doing excavation work shall call at least two working days prior to commencement of any excavation. If you are performing this type of work in California or Nevada, please call Underground Service Alert at (811) or (800) 227-2600.
Reference: Electrical Service Requirements, ER-1

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25
Q

What are the secondary climbing space dimensions for the following?
a) Arm construction
b) Triplex construction
c) Rack construction

A

a) 30 inches square
b) 30 inches square
c) Diameter of pole + 5” (2 ½” and 2 ½” on each side) × 30” deep × 38” across the
backside.
Reference: DOH, Figures DC 100-1, 100-4, and 320-1

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25
Q

What are the three basic nylon sling hitches?

A

Straight Pull
Choker Hitch
Basket Hitch
Reference: Rigging Standards Manual, Figure 84

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26
Q

When using a hand hoist, is it acceptable to use the chain and hook in a choker configuration? Why or why not?

A

No. The hook will break under stress.
Reference: Rigging Standards Manual, Figure 147

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27
Q

What is the correct type of wire used in under the arm fiber?

A

All wires must be insulated conductors.
Reference: DOH, DC 323 and G.O. 95, 54.6C2

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28
Q

What are the clearance requirements for a streetlight electrolier and secondary
conductors?

A

3’ from arm
12” from service drop
Reference: DOH, Figure SL 106-1

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28
Q

What is the maximum height at point of attachment for residential services?

A

30 feet
Reference: ESR, ESR-2 Figure 2-1

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28
Q

A clip-on ammeter reads 10 A on a 120 V conductor. What is the resistance?

A

R = E÷I
R= 120 V ÷ 10 A = 12 ohms
Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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29
Q

How much current would a 240 V heater, with 30 Ohm resistance, draw?

A

I = E÷R
1 = 240 V ÷ 30 ohms = 8 A
Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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30
Q

If a circuit has a total resistance of 20 Ohms and a current of 3 A, what is the voltage of
the circuit?

A

E=IxR
E =6 Ax 20 ohms = 120 V.
Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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31
Q

A 5000 W electric heating unit is supplied by a 240 V circuit. What is the current drawn by the heater?

A

I = P÷E
I = 5000 W ÷ 240 V = 20.8 A
Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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32
Q

How is the total resistance in a series circuit calculated?

A

It is cumulative (the sum of all resistors), i.e. Rt= R1+R2+R3 etc.
Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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33
Q
  1. What is the full load (in amps) for a 100 kVA single-phase transformer with 120/240 V secondary service?
A

I = VA ÷ E
100KVA(1000)=100,000VA
1 = 100,000 VA ÷ 240 V = 416.66 A
Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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34
Q
  1. A single-phase 120/240 V circuit is tested with a voltmeter and an ammeter with the following results: 240 V and 200 A. At the time of measurement, the service meter measures 36 kW. What is the power factor?
A

PF= W
I(E)

PF= 36,000 = .75
200A(240V)

Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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35
Q

What is the full load for a 300 kVA three-phase transformer bank with 240 V secondaries?

A

Full load amps= VA
E (1.73)

FLA= 300(1000) = 300,000 =722.5A
240 (1.73) 415.2

Reference: 2nd Step Basic AC/DC Electrical Theory Training Manual

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36
Q

What is the main benefit and drawback of a radial distribution system?

A

Benefit: Cheapest and simplest
Drawback: Least reliable. you cant pick it up from the back end
Reference: 2nd Step SCE Electrical System Overview Training Manual

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37
Q

What is the purpose of a distribution transformer?

A

Distribution transformers reduce primary voltages to secondary voltages to supply electrical service to customers.
Reference: 2nd Step SCE Electrical System Overview Training Manual

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38
Q

List four different types of generating stations.

A

Fossil fuel plants
Nuclear plants
Hydroelectric plants
Wind turbines
Reference: 2nd Step SCE Electrical System Overview Training Manual

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39
Q

What is a “B” bank substation?

A

“B” banks are SCE’s distribution transformers.
Reference: 2nd Step SCE Electrical System Overview Training Manual

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40
Q

List eight different types of “B” banks.

A

66/16 kV
66/12 kV
66/4 kV
33/12 kV
33/4 kV
16/4 kV
12/4 kV
12/2.4 kV
Reference: 2nd Step SCE Electrical System Overview Training Manual

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41
Q

What must an employee do upon entering an attended substation?

A
  1. Report to the System Operator.
    2.Enter required information in the Visitor Log.
  2. Provide System Operator with suitable contact information.
  3. Inform the System Operator when leaving the station.
    Reference: APM Rule 403.a
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42
Q

Using the transformer diagram below, draw in the wiring for a three-phase, 3-wire -
three- phase, 3-wire, with a floating neutral, delta-wye configuration.

A

Reference: 2nd Step Transformer Connections Training Manual

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42
Q

Using the transformer diagram below, draw in the wiring for a three-phase, 4-wire –
three. phase, 4-wire, wye-wye configuration.

A
43
Q

Using the transformer diagram below, draw in the wiring for a three-phase, 3-wire –
three-phase, 4-wire, delta-wye configuration.

A

Reference: 2’ Step Transformer Connections Training Manual

44
Q

What type of electrical a hazard would Linemen, working on a de-energized line that parallels an energized high voltage line, be exposed?

A

Induction
Reference: Overhead Grounding Manual, 2.1.1

45
Q

How often should the neutral of a 12 kV, 4-wire circuit be grounded?

A

At intervals up to 1,200 feet.
Reference: DOH, GR Figure GR 110-1

46
Q

When grounding multiple circuits on one structure, how are the ground conductor
sizes determined?

A

By the maximum size conductor and/or greatest fault-current duty on the structure.
Reference: Overhead Grounding Manual 3.2

47
Q

Regarding determining ground conductor sizes, how is the “Redbook” utilized?

A

The Redbook provides the highest fault duty listed for the line voltage being worked.
Reference: Overhead Grounding Manual 3.2

48
Q

What is fault duty?

A

The maximum rated current that a circuit may handle in a fault condition.
Fault Duty =FLA/Transformer impedence
Reference: 2nd Step Overhead Grounding Training Manual

49
Q

List the approved grounding mediums, in order of priority.

A

Approved ground mediums in order of priority are:
Substation ground grid (see Section 3.6.2)
Multi-grounded primary neutral (see Section 3.6.3)
Steel structures (except light duty tubular steel poles)
Anchor rods
If none of the foregoing is available, use approved temporary ground rod(s) (see Section
3.6.4)
2 at 6’ apart 30” deep
1 at 7’ deep no more than 45 degree angle
Reference: Reference: Grounding Manual 3.6.1; APM 141

49
Q

What are temporary ground rods? When would they be used?

A

Temporary ground rods are 5/8 inch copper clad steel material. Temporary ground
rod(s) may be used as an approved ground medium when priority ground mediums are
not available.
Reference: Reference: Grounding Manual 3.6.7

49
Q

Define step potential and touch potential.

A

Step Potential - The electrical potential difference between two points on the earth’s
surface, separated by distance of one pace.
Touch Potential - The electrical potential difference between a grounded metallic
structure and a point on the earth’s surface separated by a distance of a typical reach.
Reference: Reference: Grounding Manual 3.6.8

50
Q

What is the minimum height at which pole bands are to be installed?

A

12 feet
Reference: Reference: Grounding Manual 3.6.9

51
Q

On a wood pole with two pole bands installed, where is the EP located?

A

In cases where workers have installed two pole bands, the workspace EPZ will be the
area on the pole between the two pole bands.
Reference: Reference: Grounding Manual 3.6.10

52
Q

A connector on a ground assembly has broken, but it appears to be easily repaired. Is it permissible to make the repair and then use the ground assembly?

A

No. Ground assemblies shall not be modified, dissembled, repaired and/or reassembled after receiving from GARP.
Reference: OGM 5.1 “Warning”

53
Q

Explain how to phase the secondaries of two single-phase transformers?

A

-Make sure the transformers to be banked are connected to the same primaryphases and set on the same primary tap (if applicable).
-Check for proper voltage on each transformer
-Make sure the neutral is connected to establish a relationship between the two transformers.
-Using a voltmeter, check across phases between the different transformers.
Conductors with zero volts are the same phase and full voltages are indicating opposite phases.
-Check for zero volts and connect the two wires. Check for zero voltage before making any subsequent connections.
Reference: 2nd Step Transformer Connections Training Manual

54
Q

What precaution must be taken when stringing wire parallel to lines energized in excess of 35 kV?

A

When stringing parallel to lines energized in excess of 35 kV, the conductor being installed or removed shall be pulled over grounded rollers at the first structure adjacent to both the tensioning and pulling set-up.
Reference: APM Rule 214.c

55
Q

What is the most important factor for making good low resistance connections with overhead conductors? Why is this factor important?

A

CLEANLINESS is the most important requirement for good low resistance connections. Oxygen in air reacts with aluminum very rapidly to form aluminum oxide, a film highly resistant to electrical current.
Reference: DOH, CO 100.1 3.0

56
Q

Why is it important to install aluminum and ACSR conductors with the correct sag?

A

Aluminum and ASR conductors have a tendency to creep or stretch under prolonged tension greater than 20 percent of the conductor’s ultimate strength. For a conductor installed with less sag than that specified for given span length and temperature, stretching may start immediately or it may occur later when a drop in temperature further tightens the conductor. This may cause relaxation of pressure in connections. Over time, relaxation can produce overheating in connections.
Reference: DOH, CO 100.1 1.0

57
Q

Why are ASR conductors factory-greased?

A

Corrosion is aluminum’s worst enemy and moisture in contact with aluminum greatly speeds the corrosion process. Inhibitor compounds prevent the entrance and entrapment of moisture and thus prevent corrosion.
Reference: DOH, CO 100.1 2.0

58
Q

When dead-ending triplex to a crossarm, what is the minimum clearance between the bare neutral and the pole’s centerline?

A

15 inches.
Reference: DOH, Figure DC 321-1

59
Q

When dead-ending triplex in rack construction, what component is used to provide additional clearance from the pole?

A

3-spool extension rack.
Reference: DOH, Figure DC 323-1

60
Q
  1. When dead-ending triplex in rack construction, what is the minimum installation clearance from communications and/or primary lines? May this minimum be reduced? If so, how?
A

Minimum of 6 feet.
Yes. May be reduced to 4 feet with installation of a guard arm.
Reference: DOH, Figure DC 323-1

61
Q
  1. A lineman is dead-ending ACS conductor to a crossarm, and installs a copper dead end device during the work? What, if anything, is wrong with this scenario?
A

Do not use aluminum dead-end devices on copper conductors or bronze and copperdevices on ASR or aluminum conductors.
Reference: DOH, CO 100.1 7.0

62
Q

What is the acceptable range for the angle in 1/0 ACSR on an angle pole with single arm construction?

A

15 to 30 degrees
Reference: DOH, Table DC 415-1

63
Q

A 45-foot pole with one line arm, and no guys, is found deteriorated. What option(s)are available to address this problem?

A

Steel stub, fiberglass wrap, or replace
Reference: DOH, Table PO 147-1

64
Q

A 45-foot pole with one line arm at a Grade ‘A’ railroad crossing is found deteriorated. What option(s) are available to address this problem?

A

Replace the pole.
Reference: DOH, Table PO 147-1

65
Q

What method should never be used to bend a pole to achieve the desired rake?

A

Never bend poles by pulling the guy.
Reference: DOH, PO 100.7 1.8

66
Q

After removing a pole from a paved area, or an area subject to pedestrian traffic, what must be done?

A

After a pole is removed, the pole holes must be completely backfilled and thoroughly tamped. The backfill shall be leveled to grade with no depression or mound allowed. When a pole is removed from paved area or area subject to pedestrian traffic, fill top 6 inches of the hole with asphalt patch or concrete.
Reference: DOH, Table PO 100.7 2.0

67
Q

What is the minimum size ground conductor for grounding applications involving wood poles

A

6 copper

Reference: DOH, 100.1 1.5

68
Q

What is the minimum depth for lateral ground conductors?

A

18 inches below finished grade
Reference: DOH, 100.1 1.3

69
Q

How is grounding achieved for a single-phase 120/240 V secondary circuit?

A

All single-phase circuits not exceeding 250 V shall have the neutral point of the transformer grounded
All three-phase circuits not exceeding 250V shall have either a phase or a neutral grounded
G.O. 95, Rule 58.2 - states that any service not exceeding 300V must be grounded
Reference: DOH. GR 100.1 4.1

70
Q

When establishing the neutral grounds on a 4-wire system, what is the minimum clearance between the ground wire attachment point and the centerline of the pole?

A

18 inches.
Reference: DOH, Figure GR 110-1

71
Q

What is the main reason why pole top extensions are installed?

A

Pole top extensions may be used to:
* Correct insufficient minimum vertical or radial clearance situations.
* Remedy fire-damaged or deteriorated pole tops; refer to the Distribution Operation and Maintenance Policies and Procedures (DOM) manual, Section IM-2, Attachment 2.
* Support crossarms with fuseholders/cutouts, surge arresters, and primary or secondary conductor.
* Support unguyed secondary or service conductor on 3-spool or single spool racks (including extended racks/spools).
* Support primary or secondary risers.
* Support non-SCE antennas, provided the requirements in DOH, DC 222, are met.
DDS 10 5.2 D.
Reference: DDS-10 5.2 D

72
Q

What are the two types of pole top extensions? Which is preferred?

A

Wood (approved)
fiberglass (not approved)
Metal (not approved)
Reference: DDS-10 5.2 D

73
Q

When separate bond wires are run on the same pole, what is the minimum clearance that must be maintained between them?

A

6 inches
Reference: DOH, GR 300.1.6

74
Q

Below what voltage may rubber gloves be used to contact energized wood pole bond wires?

A

20 kV
Reference: APM Rule 203.a.1

75
Q

List three situations where pole stubbing is not permitted.

A

A. Poles in line of Grade ‘A’ construction.
B. Poles carrying transformers.
C. Angle poles, or poles carrying extra stresses.
Reference: DOH, PO 140.1 1.1

75
Q

What length pole stub would be used on a 60-foot pole?

A

15 feet.
Reference: DOH, Table PO 140-1

76
Q

When stubbing a 60-foot pole, how many total bands are required for attaching the
pole stub?

A

Four straps; two each, top and bottom
4” apart for 2 on bottom and 2 on top
Reference: DOH, Table PO 140-1

77
Q

For what two purposes is pole set-urethane foam used?

A

Pole straightening.
Pole setting in unstable or loose soils.
Reference: DOH, Figure PO 140-3

77
Q

What precaution should be made when installing guy wires in coastal areas?

A

A corrosion-resistant Bezinal guy wire is available for use in coastal areas and other locations where standard galvanized steel guy wire has been susceptible to severe corrosion damage.
Reference: DOH, PO 300.1 2.2

78
Q

What factors must be determined when selecting the proper sized guy wire?

A

1.Conductor tension.
2.Guy angle.
Reference: DOH, PO 300.1 2.2

79
Q

When are plastic “snapper” guy guards installed?

A

On all new and rebuild construction (except in Fire Clearing Areas).
Reference: DOH. PO 350.1

80
Q

How is the minimum anchor guy lead determined?

A

1.From Table PO 320-1 (Sheet 3) determine that each guy will support one-half of the total conductor pull.
2.Find in Table PO 320-4 (Sheet 6) a conductor pull safe for one guy that exceeds the value of step one.
3.Find in Table PO 320-2 (Sheet 4) the value under the height (guy to ground) for the corresponding height and angle.
Reference: DOH, PO 320.1

80
Q

What is the minimum clearance between the case, or hanger, of a 2.4 kV transformer and the secondary level?

A

10 inches
Reference: DOH, Figure AP 110-1

81
Q

What two checks must always be performed prior to paralleling the secondary side of transformers?

A
  1. Always check for proper voltage and phasing before paralleling the secondary side of the transformers.
    DAP AP 114 note 2
82
Q

When constructing a 3-single-phase overhead transformer bank, how is the primary neutral ground connected?

A

Primary neutral ground is to be connected to surge arrester and tank discharge gap ground, but separate from secondary neutral ground
Reference: DAP 116.2

82
Q

What is the minimum size conductor used for single-phase transformer grounds?

A

6 PGW

Reference: DOH, GR 106

83
Q

When constructing a 12/16 kV 2-single-phase transformer bank, what is the minimum distance between the primary line arm and the transformers’ fuse holder arm?

A

30 inches.
Reference: DAP 122-1

84
Q

Typically, what component would be used to mount two 2.4 kV transformers on a pole? What is the weight limit for this component?

A

A two-transformer mounting bracket.
1,600 Ibs.
Reference: DOH Figure AP 114-1

85
Q

What are the acceptable fuse types/options for 2.4/4.16/4.8 kV circuits?

A

15 kV Open Cutout
Enclosed Cutout
Bay-O-Net Cutout
8 kV ELF
14.4 kV SMU-20
Reference: DOH, Table PR 100-1

85
Q

Is it permissible for a 15 kV universal cutout to be used on a 12 kV circuit?

A

Yes, if the fault duty is less than 6.25 kA, and the circuit is located in a light contaminated area
Reference: DOH, Table PR 107-1, note 8

85
Q

For what applications (voltages) is the 14.4 kV SMU-20 used?

A

The 14.4 kV SMU-20 is used on all system voltages 16 kV and below.
Reference: DOH, Table PR 107-3, note 1

86
Q

What is the purpose of a lightning arrester? How does it work?

A

To protect apparatus from lightning strikes.
Provides a path to ground, bypassing the apparatus it is protecting.
Reference: DAP 400

87
Q

. Regarding lightning arrester selection, how are the SCE districts divided?

A

Low/medium lightning density districts
High lightning density districts
Reference: DAP 400.5

88
Q

What is the preferred method of overhead grounding?

A

Equal potential bracket grounding is the preferred method for all situations.This method requires a set of grounds between the worksite and every source of supply. In addition, an equal potential zone (workspace) shall be created at the worksite. Equal potential bracket grounding applies to any type of structure.
Reference: Overhead Grounding Manual 3.6.1 3.1

89
Q

May grounds be installed by hand? When installing grounds, are the grounds first applied to the ground medium or the conductor/equipment?

A

Always use approved live-line tools to install, relocate, and remove grounds.
Grounding devices shall be applied and removed with live line tools
Reference: Overhead Grounding Manual 2.3 10, PM Rule 141.B

90
Q

What are the maintenance requirements for firecrackers?

A

Maintenance Instructions
A continuity test with an approved ohmmeter shall be made on the device every six months. The meter should indicate between 9000 and 11000 ohms for a satisfactory test. A higher or lower reading indicates that the device is defective and should not be used. Also at this time, verify that the attaching clips are in good condition.
Reference: DOM, TE-7 5.4

91
Q

Why are firecrackers used?

A

The grounding device is used to connect one phase of a 480 V service to ground through a high resistance. This connection eliminates the possibility of a high capacitive phase to-ground voltage.
Reference: DOM, TE-7 4.2.B.1

92
Q

Typically, where is a temporary grounding device (firecracker) installed when de-energizing a three-phase bank?

A

end to one leg of the secondary, preferably on a test block or test switch.
Reference: DOM, TE-7 4.3.A

93
Q

Why would a firecracker be warm?

A

With a flow-of-fault current, the temporary grounding device will tend to heat up. If the tube of the device feels substantially warmer on removal then when installed, there is a good possibility that the customer has a ground fault. However, this does not always indicate that, if the tube is not warmer there is not customer ground.
Reference: DOM, TE-7 4.2.B.3

94
Q

What is a distribution tap line?

A

A line normally energized above 600 volts having but one source of supply that has been disconnected from its sources at a field location. Not included in the above is a line that has been disconnected from its single source of supply at a substation or generating station.
Reference: APM Definitions

95
Q

When is the performance of CPR stopped?

A

Continue performing CPR until medical services arrive and are ready to take over.
If available, change rescuers every 5 cycles (2 minutes) to avoid fatigue.
Reference: APM Rule 1015.c.7

96
Q

Describe how ground assemblies are inspected and maintained. Transmission and Distribution ground assemblies shall be disassembled, cleaned, inspected and periodically tested.

A

A clear heat shrink sleeve with date tape installed under sleeve shall be applied to each ground assembly that has passed testing. This is performed as part of the GARP.
The date tag shall indicate the month and year of testing. Grounds should not be used if the date tag is not legible, missing, or if the date is over two years old.
Reference: Overhead Grounding Manual, 5.1

97
Q

According to the Accident Prevention Manual, what size and type of rope is necessary to lower a man from a pole?

A

Rope with a safe workload rating equal to approved ½-inch hand line material shall be used when lowering a person from a pole or elevated position.
Reference: APM Rule 1022.A.3

98
Q

Where should grounded rollers be installed when stringing wire?

A

bare wires (except bare neutrals in multi-conductor cables) shall be pulled over grounded rollers at the first pole or second pole from the payout and takeup equipment and through traveling grounds between the first pole and the payout and takeup equipment. The metal frame of the wire stringing equipment shall be bonded to the traveling ground
Reference: APM 214.C

99
Q

When used to protect fused overhead apparatus, where should the lightning arresters be connected?

A

On the line side of the fuse holder.
Reference: DAP AP 400.1

99
Q

How much is a pole raked against a given strain?

A

Poles at line terminals, angles, and at other points of abnormal stress shall be given a rake against the direction of the stress, equal to the width of the pole top.
Reference: DOH, PO 100.7 1.8

100
Q

Provide the dead-end tension for the following:

A

4 ACSR - 604

1/0 ACSR -1415
336 ACSR -2768
653 ACSR -3200
#4 ACSR -604
1/0 ACSR -1415
336 ACSR -2768
653 ACSR -3200
Reference: DOH, Table PO 320-1

100
Q

What is the maximum weight of a transformer that can be bolted directly to a pole?

A

2,200 Ibs.
Reference: DAP 106

101
Q

What is the maximum dead-end tension that can be put on a slack span?

A

600lbs
Reference: DOH, CO 209. 1.1.a

102
Q

What is the Edison standard spacing for 12 kV, four-wire on cross-arms?

A

pin to pin spacing one side to the other
36”-40”-36”
inside pins 11.5” from face of pole
Reference: DOH, DC 510

103
Q
A

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