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Pole Top Equipment - Voltage Regulators Edition II © Copyright MMVII T&D PowerSkills, LLC 3504 Parliament Ct. Alexandria, LA 71303 866-880-1380 http://www.tdpowerskills.com All rights reserved. This book or any part thereof must not be reproduced in any form without the written permission of T&D PowerSkills, LLC. Printed in the United States of America on September 15, 2017 Revised July 31, 2017

T&D PowerSkills Lineman Training – Edition II Page 2 General Guidelines The Pole Top Equipment - Voltage Regulators training unit is composed of a video and associated Student Manual. The DVD contains one Course . The course is divided into Lessons , where each Lesson consists of a number of Topics . The number of Lessons and Topics will vary with each course. Recommended Sequence of Instruction 1. After the instructor’s introductory remarks, read the segment objectives found in the block at the beginning of the first segment. 2. Briefly discuss the segment objectives with the instructor and other class members. 3. View the first segment of the video. 4. Read the text segment that corresponds to the first segment of the video. 5. Answer the questions at the end of the text segment. Check your answers with the correct answers provided by the instructor. 6. Participate in a class discussion of the material just covered. Ask any questions you might have concerning the material in the video and the text, and note any additional information given by the instructor. 7. Before proceeding, be sure you understand the concepts presented in this segment. 8. Work through all segments in this manner. 9. A Course Test covering all the material will be administered by the instructor upon completion of the unit. 10. Additional instruction and testing may be provided, at the instructor’s discretion. This recommended sequence may be modified slightly by the instructor due to scheduling or other special considerations. OSHA Regulations Snap-Shot This T&D PowerSkills Training workbook is designed to be used in conjunction with the associated training video. OSHA Regulations, primarily in 1926.Subpart V, 1910.269 and 1910.268 will be used in conjunction with this training unit. Where applicable, regulations will be highlighted and placed in a box like this. Regulations are used that are in force at the time of the workbook printing. Instructors and students are expected to review the current OSHA Regulations to familiarize the student with the safety requirements expected by USDOL OSHA, specifically as they relate to the topic being discussed. This information is an important part of this training unit.

Field Performance Requirements (FPR) NAME: ______________________________ #___________ SECTION: OVERHEAD DISTRIBUTION - DE-ENERGIZED UNIT(S): Pole Top Equipment - Voltage Regulators REQUIREMENTS SUPERVISOR SIGN-OFF VG ACC NI NA SEGMENT 1 – POLE TOP VOLTAGE REGULATORS 1.1 Can describe the construction and operation of induction voltage regulators .....     1.2 Can describe the construction and operation of step voltage regulators .............     SEGMENT 2 – TROUBLESHOOTING POLE TOP VOLTAGE REGULATORS 2.1 Can describe the basic parts of a step voltage regulator installed on an overhead feeder ............................................................................................     2.2 Can demonstrate approved procedures for troubleshooting a malfunctioning step voltage regulator ...........................................................................................     SEGMENT 3 – REPLACING POLE TOP VOLTAGE REGULATORS 3.1 Can demonstrate approved procedures and safe work practices for replacing a pole top voltage regulator ....................................................................................     __________________________ __________________________ ____________________ Apprentice’s Signature Supervisor's Signature Date Complete  Incomplete  VG = Very Good ACC = Acceptable NI = Needs Improvement NA = Not Able to Complete on this Crew

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T&D PowerSkills Lineman Training – Edition II Page 4 NOTES: OSHA Regulations Snap-Shot 1910.269(a)(2)(vii) The training shall establish employee proficiency in the work practices required by this section and shall introduce the procedures necessary for compliance with this section. 1910.269(a)(2)(viii) The employer shall ensure that each employee has demonstrated proficiency in the work practices involved before that employee is considered as having completed the training required by paragraph (a)(2) of this section. Note 1 to paragraph (a)(2)(viii) : Though they are not required by this paragraph, employment records that indicate that an employee has successfully completed the required training are one way of keeping track of when an employee has demonstrated proficiency. Note 2 to paragraph (a)(2)(viii) : For an employee with previous training, an employer may determine that that employee has demonstrated the proficiency required by this paragraph using the following process: (1) Confirm that the employee has the training required by paragraph (a)(2) of this section, (2) Use an examination or interview to make an initial determination that the employee understands the relevant safety-related work practices before he or she performs any work covered by this section, and (3) Supervise the employee closely until that employee has demonstrated proficiency as required by this paragraph.

Table of Contents Segment 1: Pole Top Voltage Regulators 7 1.1 Induction Regulators 9 1.2 Step Regulators 15 1.3 Voltage Control Circuitry 23 Segment 2: Troubleshooting Pole Top Voltage Regulators 30 2.1 Regulator Construction 30 2.2 Troubleshooting a Voltage Regulator 36 Segment 3: Pole Top Voltage Regulator Replacement 38 3.1 Preparations and Regulator Removal 38 3.2 Regulator Replacement 45

T&D PowerSkills Lineman Training – Edition II Page 6 Table of Figures Figure 1-1: Typical Voltage Regulator ...................................................................................................... 8 Figure 1-2: Parts of an Induction Regulator ............................................................................................. 9 Figure 1-3: Primary and Secondary Winding Voltages ........................................................................... 10 Figure 1-4: Load Side Voltage Reduced by 10% ..................................................................................... 11 Figure 1-5: Load Side Voltage Reduced by 5% ...................................................................................... 12 Figure 1-6: Neutral Position .................................................................................................................... 13 Figure 1-7: Load Side Voltage Increased by 10% ................................................................................... 14 Figure 1-8: Parts of a Step Regulator ...................................................................................................... 15 Figure 1-9: Taps, Contacts, and Bridging Reactor .................................................................................. 16 Figure 1-10: Bridging Reactor Between Taps (In "Boost" Position) ...................................................... 17 Figure 1-11: Reversing Switch ............................................................................................................... 18 Figure 1-12: Step Regulator at Neutral Position ..................................................................................... 19 Figure 1-13: Step Regulator at Step 1 ..................................................................................................... 20 Figure 1-14: Step Regulator at "Raise" Step 2 ........................................................................................ 21 Figure 1-15: "Full Boost" Position ......................................................................................................... 22 Figure 1-16: "Full Buck" Position .......................................................................................................... 23 Figure 1-17: Voltage Control Circuit ...................................................................................................... 24 Figure 1-18: Control Circuit Voltage within Bandwidth ........................................................................ 25 Figure 1-19: Control Circuit in "Lower" Position .................................................................................. 26 Figure 1-20: Control Circuit in "Raise" Position .................................................................................... 27 Figure 2-1: Single-Phase Step Voltage Regulator .................................................................................. 30 Figure 2-2: Single-Phase Step Voltage Regulator Bushings ................................................................... 31 Figure 2-3: Position Indicator Dial ......................................................................................................... 32 Figure 2-4: Oil Level Gauge ................................................................................................................... 33 Figure 2-5: Electromechanical and Solid-State Voltage Regulator Controls .......................................... 34 Figure 2-6: Switches ............................................................................................................................... 35 Figure 3-1: Zeroing a Voltage Regulator ................................................................................................ 39 Figure 3-2: Removing Jumper ................................................................................................................ 42 Figure 3-3: Securing Control Mechanism to Tank .................................................................................. 43 Figure 3-4: Regulator Rigged for Removal from Pole ........................................................................... 44

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Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 7 Segment 1: Pole Top Voltage Regulators OSHA Regulations Snap-Shot Voltage tends to decrease along a distribution feeder. It can also fluctuate above and below acceptable levels due to changing load conditions on the system. To maintain service to customers in a useful range, voltage regulators are often installed on the system. 1910.269 (c) Job Briefing (1) Before each job (i) In assigning an employee or group of employees to perform a job, the employer shall provide the employee in charge of the job with all available information that relates to the determination of existing characteristics and conditions required by paragraph (a)(4) of this section. (ii) The employer shall ensure that the employee in charge conducts a job briefing that meets paragraph (c)(2), (c)(3) and (c)(4) of this section with the employees involved before they start each job. (c)(2) Subjects to be covered. The briefing shall cover at least the following subjects: hazards associated with the job, work procedures involved, special precautions, energy-source controls, and personal protective equipment requirements. (c)(3) Number of briefings. (i) If the work or operations to be performed during the day or shift are repetitive and similar, at least one job briefing shall be conducted before the start of the first job of each day or shift. (ii) Additional job briefings shall be held if significant changes, which might affect the safety of the employees, occur during the course of the work. (c)(4) Extent of the briefing. (i) A brief discussion is satisfactory if the work involved is routine and if the employees, by virtue of training and experience, can reasonably be expected to recognize and avoid the hazards involved in the job. (ii) A more extensive discussion shall be conducted: (A) If the work is complicated or particularly hazardous, or (B) If the employee cannot be expected to recognize and avoid the hazards involved in the job. Note to paragraph (c)(4) The briefing must address all of the subjects listed in paragraph (c)(2) of this section. OBJECTIVES: • Describe the construction and operation of induction voltage regulators and step voltage regulators. • Explain the operation of a voltage regulator control circuit.

Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 8 Voltage regulators are a type of variable ratio voltage transformer. They are designed to respond automatically to a voltage that is above or below a predetermined level by changing the relationship between the transformer windings inside the regulator. This change adjusts the voltage on the load side of the regulator so that it remains within acceptable limits. Two commonly used types of pole top voltage regulators are induction regulators and step regulators. Both types are capable of either raising or lowering voltage. In general, the maximum amount that voltage is raised or lowered is 10%. Figure 1-1: Typical Voltage Regulator

Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 9 1.1 Induction Regulators Induction regulators adjust voltage in a continuous fashion. Figure 1-2 is a simplified illustration of an induction regulator. The illustration shows a distribution feeder with a break in the line, so that there is a line side and a load side of the feeder. The primary, or moving, winding of the induction regulator is connected to the line side of the feeder at one end, and to a ground on the other end. The secondary, or stationary, winding is connected in series with the feeder. Figure 1-2: Parts of an Induction Regulator

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 10 During normal operation, there is a voltage on both the primary and secondary windings. This voltage is indicated by white arrows in Figure 1-3. The current on the primary winding forms a magnetic field, which can cut across and magnetically couple with the secondary winding. This magnetic field induces a voltage in the secondary winding that is opposite in direction to the voltage on the primary winding. The induced voltage is indicated by the gray arrow in Figure 1-3. Figure 1-3: Primary and Secondary Winding Voltages For the purpose of comparison, the examples that follow show a constant voltage level on the line side of the regulator and the effect of the regulator windings on the load side. In reality, the voltage on the line side of the regulator varies, and the objective is to maintain a constant voltage level on the load side.

Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 11 When the direction of the voltage induced in the secondary winding is opposite to the existing voltage in the secondary winding, the existing voltage is decreased, or "bucked." In Figure 1-4, the two windings are lined up so that the magnetic coupling between them induces the maximum voltage in the secondary winding. Since the direction of the induced voltage is opposite to the direction of the voltage already in the secondary winding, the voltage on the load side of the regulator is reduced by a full 10 percent. For example, if the line voltage is 2400 volts, the primary winding in the "full buck" position causes the voltage on the secondary winding to decrease by 240 volts. The voltage on the load side of the regulator is then 2160 volts. Figure 1-4: Load Side Voltage Reduced by 10%

Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 12 When the primary winding is rotated to a 45-degree position in relation to the secondary winding (Figure 1-5), the effect of the magnetic coupling is reduced to 5%, or 120 volts. The load side voltage then becomes 2280 volts. Figure 1-5: Load Side Voltage Reduced by 5%

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Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 13 When the primary winding is rotated to a 90-degree position in relation to the secondary winding (Figure 1-6), there is no magnetic coupling between the two windings. The voltage is the same on both the line side and the load side. This position is usually referred to as the neutral position. Figure 1-6: Neutral Position As the primary winding continues to rotate, the direction of the voltage induced in the secondary winding changes. The induced voltage then increases, or "boosts," the voltage on the secondary winding.

Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 14 When the primary winding is at its "full boost" position, the voltage on the load side of the regulator is increased by full 10 percent. In Figure 1-7, the voltage is increased by 240 volts to 2640 volts. Figure 1-7: Load Side Voltage Increased by 10% The movement of the primary winding in an induction voltage regulator is continuous. As a result, the change in the voltage is also continuous.

Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 15 1.2 Step Regulators A step voltage regulator has a number of taps. It responds to voltage changes by moving from one tap to another in specific steps. Figure 1-8 is a simplified illustration of a step regulator. The regulator has two windings: a shunt winding and a series winding. Neither winding moves. The shunt winding is connected on one end to the load side of the phase. The other end is connected to a ground. Figure 1-8: Parts of a Step Regulator

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 16 The feeder is interrupted at the regulator so that there is a line side and a load side of the feeder. The series winding is connected in series between the two sides of the feeder. Figure 1-9 shows a section of the step regulator. The step regulator has eight taps connected at different places on the series winding. Each tap ends in a contact. In Figure 1-9, the contacts are numbered 1 through 8. A ninth contact, which is not connected to the series winding, provides the regulator with a neutral position. A bridging reactor is used to connect the taps to the line side of the feeder. Figure 1-9: Taps, Contacts, and Bridging Reactor

Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 17 When the reactor is moved from tap to tap, it changes the number of turns on the series winding that are part of the circuit. (In this example, for clarity, the whole bridging reactor is moved. In reality, only the contacts at the end of the bridging reactor move.) The bridging reactor can only move one step at a time when it changes position. It prevents the circuit from breaking between taps by maintaining contact with at least one tap at all times. When the reactor makes contact with two adjacent taps (Figure 1-10), it provides an intermediate position and compensates for the difference in voltage between the two taps. In this way, the number of steps between neutral and "full buck" or "full boost" is increased from 8 to 16. Figure 1-10: Bridging Reactor Between Taps (In "Boost" Position)

Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 18 For the step regulator in this example, the maximum increase or decrease in the voltage is 10 percent. Each of the 16 steps above and below the neutral position represents a voltage change of 5/8 of one percent. On a 2400-volt primary line, each step changes the voltage by approximately 15 volts. The ends of the series winding are connected through a reversing switch (Figure 1-11) to the shunt winding on the load side. The reversing switch allows the direction of the voltage to be changed in the series winding so that the same eight taps can be used for both increasing and decreasing the voltage on the shunt winding. When the switch is in the "R" position, the voltage is raised. When the switch is in the "L" position, the voltage is lowered. Figure 1-11: Reversing Switch

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Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 19 Figures Figure 1-12 through Figure 1-16 illustrate step voltage regulator operation. To begin (Figure 1-12), line voltage on the circuit is 2400 volts. The bridging reactor is in the neutral position, so the load side voltage is also 2400 volts. The current flow through the circuit is shown as a white line. Figure 1-12: Step Regulator at Neutral Position

Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 20 In Figure 1-13, the reversing switch is in the "R" position, and the bridging reactor has moved counterclockwise so that contacts are between the neutral position and the first tap contact. Under these conditions, the voltage is raised by 5/8 of 1%, or 15 volts, to 2415 volts. Figure 1-13: Step Regulator at Step 1

Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 21 Moving the contact arm one more step counterclockwise so that it is fully on the first contact (Figure 1-14) is step 2. The line voltage is increased by another 5/8 of 1% for a total of 1¼%, or 2430 volts. Figure 1-14: Step Regulator at "Raise" Step 2

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 22 This process can continue until the bridging reactor is fully on the last contact, which is the "full boost" position (Figure 1-15). At this point, the voltage is 2640 volts. Figure 1-15: "Full Boost" Position

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Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 23 From the neutral position, changing the reversing switch to the "L" position causes the load side voltage to be lowered. The bridging reactor moves clockwise one step at a time. Voltage is lowered in 16 steps of 5/8 of 1% until the "full buck" position is reached (Figure 1-16). The voltage on the load side of the regulator is a full 10% lower than the line side, or 2160 volts. Figure 1-16: "Full Buck" Position 1.3 Voltage Control Circuitry Both induction regulators and step regulators use a control circuit to sense voltage fluctuations and keep the voltage within preset limits. Several kinds of electromechanical and solid-state control units are available, but they all operate on similar principles.

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 24 Figure 1-17 is a simplified illustration of an electromechanical control circuit. The circuit is powered through a step-down transformer, which is connected at the load side of the regulator so that the voltage on the circuit is in the secondary range. The circuit has a motor, which is connected through two motor control relays. The motor is used to move the windings or to change the taps, depending on the type of regulator used. One relay operates the motor in the direction that raises the primary voltage, and the other relay operates the motor to lower the primary voltage. Figure 1-17: Voltage Control Circuit A beam positioned on a pivot between two contacts has a voltage in the 120-volt range. This voltage is used to operate the motor control relays. The beam is moved by a solenoid, and its movement is balanced by a spring, which pulls the beam away from the solenoid. The secondary voltage that energizes the solenoid is always proportional to the primary voltage on the load side of the regulator. In a 2400-volt system, this proportion is 20 to 1.

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Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 25 The control circuit represented in Figure 1-18 is adjusted to a range of from 120.5 to 123.5 volts, or a total range of 3 volts. This range is called the bandwidth. The bandwidth prevents the mechanism of the regulator from having to respond to minor voltage fluctuations, and thus prevents excess wear and tear on the regulator. As long as the voltage on the control circuit remains between 120.5 and 123.5 volts, the control circuit will not cause a voltage adjustment. The control circuit can be set so that the beam is zeroed between the two contacts at a specific voltage, in this case, 122 volts. The current path in the control circuit in Figure 1-18 is shown as a white line. Figure 1-18: Control Circuit Voltage within Bandwidth

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 26 If the load voltage increases so that the stepped-down voltage on the solenoid is above 122 volts, the beam moves toward the lower contact. At 123.5 volts, the beam touches the lower contact (Figure 1-19), closing the circuit to the lowering motor control relay. The motor then adjusts the windings of the regulator to decrease the load voltage. Decreasing the load voltage causes the solenoid to move the beam back to a position between the two contacts. Figure 1-19: Control Circuit in "Lower" Position

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Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 27 If the load voltage decreases so that the stepped-down voltage on the solenoid is below 122 volts, the beam moves toward the upper contact. At 120.5 volts, the beam touches the upper contact (Figure 1-20), and the motor adjusts the windings of the regulator to increase the load voltage. Increasing the voltage causes the solenoid to move the beam back to its center position. Figure 1-20: Control Circuit in "Raise" Position

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 28 Section Quiz 1-1. A _______________________ is a type of variable ratio voltage transformer that is designed to respond to voltage changes above or below a predetermined level. 1-2. A voltage regulator adjusts voltage on the _____________ side of the regulator so that it (line, load) remains within acceptable limits. 1-3. A(n) (a) ___________________ regulator adjusts voltage in a continuous fashion, while a(n) (b) __________________ regulator adjusts voltage in a number of defined stages. 1-4. True or False. When the direction of the voltage induced in the secondary winding of a regulator is opposite to the direction of the existing voltage in the secondary winding, the existing voltage is decreased, or "bucked." 1-5. When the primary winding of an induction regulator is rotated to a 90-degree position in relation to the secondary winding, the voltages on the line side and the load side of the regulator are _____________________. (the same, different) 1-6. Circle the correct answer. A step regulator has which of the following types of windings? a) Series b) Step c) Shunt d) All of the above e) Only a and c 1-7. A __________________________ reactor prevents a circuit from breaking between the taps of a step regulator by maintaining contact with at least one tap at all times. 1-8. True or False. A reversing switch in a step regulator allows the same eight taps to be used for

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Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 29 both increasing and decreasing voltage. 1-9. Voltage regulators use a _____________________ circuit to sense voltage fluctuations and keep voltage within preset limits. 1-10. If the bandwidth of a voltage regulator is set at 120.5 volts to 123.5 volts, at 123.5 volts, the control circuit will cause the voltage regulator to ______________ the voltage on the load side (raise, lower) of the regulator.

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 30 Segment 2: Troubleshooting Pole Top Voltage Regulators 2.1 Regulator Construction Single-phase step voltage regulators are commonly installed on overhead feeders. The tank of the regulator shown in Figure 2-1 has three bushings on its top. Figure 2-1: Single-Phase Step Voltage Regulator OBJECTIVES: • Describe the basic parts of a step voltage regulator installed on an overhead feeder. • Describe or demonstrate how to troubleshoot a malfunctioning step voltage regulator.

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Troubleshooting Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 31 As shown in Figure 2-2, one bushing is for the connection to the line, one is for the connection to the load, and one is for the connection to the pole ground. Surge arresters are connected to the line and load bushings. On delta systems, there is no connection to ground. The third bushing is connected to another phase. Figure 2-2: Single-Phase Step Voltage Regulator Bushings OSHA Regulations Snap-Shots 1910.269 (a) (2) Training. (i) All employees performing work covered by this section shall be trained as follows: (i)(A) Each employee shall be trained in and familiar with, the safety-related work practices, safety procedures, and other safety requirements in this section that pertain to their respective job assignments. (i)(B) Each employee shall also be trained in and familiar with any other safety practices, including applicable emergency procedures (such as pole top and manhole rescue), that are not specifically addressed by this section but that are related to his or her work and are necessary for his or her safety. (i)(C) The degree of training shall be determined by the risk to the employee for the hazard involved. (ii) Each qualified employee shall also be trained and competent in (ii)(A) The skills and techniques necessary to distinguish exposed live parts from other parts of electric equipment, (ii)(B) The skills and techniques necessary to determine the nominal voltage of exposed live parts, (ii)(C) The minimum approach distances specified in this section corresponding to the voltages to which the qualified employee will be exposed, and the skills and techniques necessary to maintain those distances, (ii)(D) The proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools for working on or near exposed energized parts of electric equipment, and (ii)(E) The recognition of electrical hazards to which the employee may be exposed and the skills and techniques necessary to control or avoid these hazards. Surge Arrestors Ground Bushing Load Bushing Line Bushing

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 32 A dial called a position indicator (Figure 2-3) is mounted on the regulator tank so that it can be viewed from below. The dial’s scale has a zero, or neutral, position in its center, and 32 marks to indicate the 16 steps above and below the 0 mark. A pointer indicates the regulator's present tap position. Two drag hands indicate the regulator's highest and lowest tap positions since the hands were last reset. Figure 2-3: Position Indicator Dial Pointer “Drag” Hands

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Troubleshooting Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 33 The regulator in this example uses oil as an arc extinguishing medium and insulation. An oil level gauge (Figure 2-4) is located on the tank to allow the oil level to be checked. Always check oil level prior to operating regulator Figure 2-4: Oil Level Gauge OSHA Regulations Snap-Shot 1910.333 (c) Working on or near exposed energized parts. (1) Application. This paragraph applies to work performed on exposed live parts (involving either direct contact or by means of tools or materials) or near enough to them for employees to be exposed to any hazard they present. (2) Work on energized equipment. Only qualified persons may work on electric circuit parts or equipment that have not been deenergized under the procedures of paragraph (b) of this section. Such persons shall be capable of working safely on energized circuits and shall be familiar with the proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools. Oil Level

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 34 This voltage regulator has a solid-state control mechanism, which is mounted in a metal box located lower on the utility pole (Figure 2-5). The box is permanently attached to the regulator by a control cable. When the regulator is changed out, the control mechanism and cable are usually changed, as well. The control mechanism enables the voltage regulator to respond automatically to changes in line voltage, and it can also be used to operate the regulator manually. The mechanism is powered by a fused 120-volt source. Figure 2-5: Electromechanical and Solid-State Voltage Regulator Controls OSHA Regulations Snap-Shot 1910.269 (w) (7) Backfeed. When there is a possibility of voltage backfeed from sources of cogeneration or from the secondary system (for example, backfeed from more than one energized phase feeding a common load), the requirements of paragraph (l) of this section apply if the lines or equipment are to be worked as energized, and the requirements of paragraphs (m) and (n) of this section apply if the lines or equipment are to be worked as deenergized.

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Troubleshooting Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 35 In this example, the voltage regulators for each phase are mounted on separate poles. The phase is broken by in-line insulators at the pole, and the regulator is connected to each side of the phase through a pair of permanently mounted disconnect switches and a bypass switch (Figure 2-6). The switches in this example are mounted on a common base, although other methods of connection may be used. Figure 2-6: Switches Under normal conditions, the disconnect switches are closed and the bypass switch is open. Power from the line side is fed down through the voltage regulator and then out to the load side. When the regulator is in the neutral, or zero, position, it can be taken off line by closing the bypass switch and opening both disconnect switches. (Before this is done, it is important to make sure that the regulator is in the neutral position and off.) If the regulator is not in the neutral position, a short circuit could result. There is also a danger of arcing, due to the difference between the line and load voltages. This could cause personal injury and equipment damage.) Bypass Switch (Closed) Load Disconnect Load Disconnect

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 36 2.2 Troubleshooting a Voltage Regulator When a problem occurs with a voltage regulator, a visual inspection is usually made to narrow down the possible causes of the problem. For example, the jumpers and switches are checked for any signs of heat damage or corrosion. The regulator's tank and bushings are checked for any signs of damage that could affect the unit's performance, such as broken bushings or obvious oil leaks. The oil level gauge is also checked. A low oil level may indicate a small leak over a period of time. In addition, a low oil level could cause heat damage to the internal mechanism of the regulator. The regulator used as an example in this part of the program has limiting tabs on the "raise" and "lower" sides of the position indicator. These tabs prevent movement beyond the eighth step, so that the regulator can only vary the line voltage by a maximum of 5%. During a visual inspection, the positions of the needle and the drag hands on the position indicator should be noted. These positions can be compared with those of other regulators to see if one unit is obviously malfunctioning. The control cable, the control mechanism, and the control cable's connections to the regulator tank should be checked for signs of damage. The control mechanism is checked to make sure that it is still intact, and a voltage reading is taken to make sure that the mechanism is still energized. After the visual inspection of the first voltage regulator is complete, the other two regulators are inspected. In the video presentation, when the third regulator was inspected, the crew noticed that the regulator was in the "full boost" position, as shown by the needle on the position indicator. This was a much higher position than the other two regulators. Further testing indicated that the regulator was locked in that tap position and could not be changed manually. The crew reported the malfunctioning unit to the proper authorities. Arc Flash Hazard OSHA evaluates compliance with its electrical safety regulations, OSHA 1910 Subpart S and OSHA 1926 Subpart K, using the comprehensive information in NFPA 70E . While OSHA tells you what to do to avoid electrical dangers, this vital Standard tells you how . Please refer to the National Fire Protection Standard: NFPA 70E for Arc Flash protection compliance.

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Troubleshooting Pole Top Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 37 Section Quiz 2-1. A dial called a ________________________ shows the present tap position of a typical step voltage regulator. 2-2. True or False. Drag hands indicate the highest and lowest voltages on a feeder. 2-3. Why must a voltage regulator be in its neutral, or zero, position before it is bypassed? 2-4. True or False. The tap position of each regulator on a three-phase feeder is noted and compared to the others to determine an obvious malfunction. 2-5. Circle the correct answer. Which of the following checks are typically made during the visual inspection of a voltage regulator? a) Jumpers and switches checked for heat damage and corrosion b) Tank and bushings checked for breakage or obvious oil leaks c) Oil level gauge checked for proper oil level d) Control mechanism and related connections checked for damage e) All of the above

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 38 Segment 3: Pole Top Voltage Regulator Replacement The video presentation for this part of the program demonstrates one method of safely changing out a pole top single-phase step voltage regulator. The demonstration is intended to illustrate the basic tasks associated with the job. The actual steps performed during a changeout will depend on the design and installation of the voltage regulator involved and on specific company procedures. The basic tasks involved in a voltage regulator changeout are similar to those involved in changing out other types of equipment. They generally include holding a tailgate session, electrically and physically isolating the regulator, rigging and replacing the regulator, and connecting and energizing the new regulator. 3.1 Preparations and Regulator Removal When the crew arrives at the job site, the trucks are parked, and the work area is safely marked off. Then a tailgate session is held to discuss the steps involved in the job and specific safety considerations. Crewmember job assignments are made so that each person is aware of his responsibilities during the changeout, as well as those of the other crewmembers. The replacement voltage regulator and control unit should be visually inspected to verify that they are the proper size and type for the job. They should also be checked for any damage that might have occurred during shipping and handling. If the control box and cable to the regulator are permanently attached to the old unit, they are replaced along with the regulator. The new control cable and control box should be inspected for any defects or damage. OBJECTIVES: • Describe one method of safely zeroing and isolating a voltage regulator before changeout. • Describe or demonstrate how to safely remove a step voltage regulator from an overhead feeder and install a replacement unit.

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Pole Top Voltage Regulator Replacement T&D PowerSkills Lineman Training – Edition II Page 39 After the tailgate session, company procedures should be followed for notifying the proper authorities that the voltage regulators must be bypassed to replace the defective regulator. Bypassing all three voltage regulators will keep the voltage balanced on the feeder. In this example, each of the three voltage regulators is located on a separate utility pole. (In this example, all three voltage regulators are bypassed, but that may not always be necessary. Company regulations specify the proper procedures for changing out voltage regulators in specific systems.) Before each regulator is bypassed, it must be manually zeroed (Figure 3-1) so that there is no potential difference between the two sides of the phase. In the video example, the control switch in the control box was used to move the regulator mechanism to the neutral position, one step at a time. When the neutral position was reached, the bypass switch for the regulator could be closed, and the two disconnect switches could be opened. Figure 3-1: Zeroing a Voltage Regulator

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 40 In the video demonstration, when the crew tried to move the third regulator to the neutral position, the controls did not respond. This regulator was stuck in its "full boost" position. Under these conditions, there is a potential difference between the two sides of the regulator, and it would be dangerous to attempt to close the regulator's bypass switch. One way that the regulator could be bypassed was to have the load dropped on the feeder, bypass the regulator while the line is de-energized, and then re- energize the feeder. In the video demonstration, the load dispatcher was contacted, and arrangements were made to have the feeder dropped. When the dispatcher confirmed that the load on the feeder had been dropped, a statiscope was used to verify that the feeder was de-energized. When a statiscope is used, it is first tested on a known voltage source to ensure that it is operating properly. Then the phase is tested to verify that the line is dead. Finally, the statiscope is rechecked to make sure that it is still working properly. While the line is de-energized, the bypass switch can be closed. The two disconnect switches are then opened to ensure that the regulator will remain de-energized and electrically isolated. The load dispatcher is then contacted again, and the feeder is re-energized. OSHA Regulations Snap-Shot 1910.134 (f) Training. (1) The employer shall provide training to each employee who is required by this section to use PPE. Each such employee shall be trained to know at least the following: (i) When PPE is necessary; (ii) What PPE is necessary; (iii) How to properly don, doff, adjust, and wear PPE; (iv) The limitations of the PPE; and, (v) The proper care, maintenance, useful life and disposal of the PPE.

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Pole Top Voltage Regulator Replacement T&D PowerSkills Lineman Training – Edition II Page 41 OSHA Regulations Snap-shot 1910.269(p) (4) Operations near energized lines or equipment. (i) Mechanical equipment shall be operated so that the minimum approach distances, established by the employer under paragraph (l)(3)(i) of this section, are maintained from exposed energized lines and equipment. However, the insulated portion of an aerial lift operated by a qualified employee in the lift is exempt from this requirement if the applicable minimum approach distance is maintained between the uninsulated portions of the aerial lift and exposed objects having a different electrical potential. (ii) A designated employee other than the equipment operator shall observe the approach distance to exposed lines and equipment and provide timely warnings before the minimum approach distance required by paragraph (p)(4)(i) of this section is reached, unless the employer can demonstrate that the operator can accurately determine that the minimum approach distance is being maintained. (iii) If, during operation of the mechanical equipment, that equipment could become energized, the operation shall also comply with at least one of paragraphs (p)(4)(iii)(A) through (p)(4)(iii)(C) of this section. (A) The energized lines exposed to contact shall be covered with insulating protective material that will withstand the type of contact that could be made during the operation. (B) The mechanical equipment shall be insulated for the voltage involved. The mechanical equipment shall be positioned so that its uninsulated portions cannot approach the lines or equipment any closer than the minimum approach distances, established by the employer under paragraph (l)(3)(i) of this section. (C) Each employee shall be protected from hazards that could arise from mechanical equipment contact with the energized lines or equipment. The measures used shall ensure that employees will not be exposed to hazardous differences in electrical potential. Unless the employer can demonstrate that the methods in use protect each employee from the hazards that could arise if the mechanical equipment contacts the energized line or equipment, the measures used shall include all of the following techniques: (1) Using the best available ground to minimize the time the lines or electric equipment remain energized, (2) Bonding mechanical equipment together to minimize potential differences, (3) Providing ground mats to extend areas of equipotential, and (4) Employing insulating protective equipment or barricades to guard against any remaining hazardous potential differences. Note : Appendix C to this section contains information on hazardous step and touch potentials and on methods of protecting employees from hazards resulting from such potentials.

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 42 To physically isolate the regulator so that it can be rigged for removal, the three jumpers are disconnected (Figure 3-2). Before this is done, however, each jumper should be marked to indicate load or line. After all three jumpers are disconnected, the other primary equipment should be covered to make the work area safe. Figure 3-2: Removing Jumper Jumper

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Pole Top Voltage Regulator Replacement T&D PowerSkills Lineman Training – Edition II Page 43 The case ground is then disconnected, and the control box is disconnected from the pole. The control box and cable were sent up and secured to the tank of the regulator (Figure 3-3). Figure 3-3: Securing Control Mechanism to Tank OSHA Regulations Snap-Shot 1926.251 Rigging equipment for material handling (a) General. (1) Rigging equipment for material handling shall be inspected prior to use on each shift and as necessary during its use to ensure that it is safe. Defective rigging equipment shall be removed from service. (2) Rigging equipment shall have permanently fixed and legible identification markings as prescribed by the manufacturer that indicate the recommended safe working load, and shall not be loaded in excess of its recommended safe working load. (3) Rigging equipment, when not in use, shall be removed from the immediate work area so as not to present a hazard to employees.

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 44 To rig the regulator unit for removal, the boom of a derrick was maneuvered into position, and a line was attached to the regulator's lifting lugs with a sling (Figure 3-4). A tag line was attached to the regulator tank and run down to a crewmember on the ground. A test strain was then taken to test the rigging. Figure 3-4: Regulator Rigged for Removal from Pole After the rigging is checked, the bolts holding the regulator to the pole are loosened, and the unit is lifted free of the pole. As the regulator is lowered to the ground, the tag line can be used to stabilize the regulator and guide it around obstacles.

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Pole Top Voltage Regulator Replacement T&D PowerSkills Lineman Training – Edition II Page 45 3.2 Regulator Replacement When the old regulator reached the ground, the rigging was removed and attached to the replacement unit. The replacement regulator was then lifted into position on the pole and bolted into place. The regulator can then be physically connected to the system. After the control cable is unwound, the control box and cable are lowered to their position on the pole, and then secured to the pole. The end of the wire attached to the pole ground is then cleaned, and the connection is made to the regulator tank (or case ground). The end of each jumper is cleaned and attached to its proper bushing on the regulator. Finally, the rubber gear is removed from the rest of the primary equipment and sent down to the ground. Before the regulator can be put into service, it must be energized and tested. The regulator used as an example in the video demonstration had a built-in transformer to provide secondary control power. (Other regulators may be powered from an outside source and may be tested differently.) In this example, the disconnect switch on the line side of the regulator was closed first. Closing this switch energizes the regulator and provides power to the step-down transformer inside the tank, which allows the controls to be operated. The bypass switch remains closed, however, keeping the regulator bypassed. If the regulator is not in the neutral position, the control switch in the control box is operated until the regulator mechanism moves into the neutral position. The regulator used as an example in the video was preset to raise or lower the voltage 5% instead of a full 10%. To test the mechanism, the crew moved the control switch to the "lower" position and made sure that the regulator moved 8 steps to its maximum "lower" position. Next, the reversing switch in the control box was moved to the "raise" position, and the regulator was moved to its maximum "raise" position. The steps were visually confirmed with the pointer position on the dial. The mechanism was then moved back to the neutral position. The drag hands were reset, and the bandwidth was set. Any additional testing required by the company or manufacturer may also be done at this time.

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 46 Before the regulator is put back on line, it is important to verify that the control mechanism is in the neutral position, that the control switch is in the "off" position, and that the main switch in the control box is turned off. This prevents the voltage regulator from operating while the unit is put back on line. If the regulator is in any position other than neutral, it may cause a short circuit, equipment damage, and personal injury. The disconnect switch on the load side of the regulator is closed, and the bypass switch is opened, so that the regulator is carrying the full load. When the crew is satisfied with the regulator unit's operation, the control box can be re-energized, and the control switch can be turned to the automatic position, placing the unit back on line. The other two regulators are then reset and returned to service, and the proper authorities are notified that the job is complete. OSHA Regulations Snap-Shot 1910.269 (l) (6) Making Connections. The employer shall ensure that connections are made as follows: (i) In connecting deenergized equipment or lines to an energized circuit by means of a conducting wire or device, an employee shall first attach the wire to the deenergized part: (ii) When disconnecting equipment or lines from an energized circuit by means of a conducting wire or device, an employee shall remove the source end first; and (iii) When lines or equipment are connected to or disconnected from energized circuits, an employee shall keep loose conductors shall be kept away from exposed energized parts.

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Pole Top Voltage Regulator Replacement T&D PowerSkills Lineman Training – Edition II Page 47 Section Quiz 3-1. Circle the correct answer. Which of the following are basic tasks associated with the changeout of a pole top step voltage regulator? a) Tailgate session b) Physically and electrically isolating the old unit c) Replacing the old unit d) Connecting the replacement unit e) Energizing the replacement unit f) All of the above 3-2. True or False. Before a changeout is begun, the replacement unit and associated equipment should be visually inspected for damage that might have occurred during shipping and handling. 3-3. _______________________ and bypassing each regulator during a changeout ensures that (Resetting, Zeroing) that there is no potential difference between the two sides of the phase. 3-4. True or False. If a voltage regulator cannot be zeroed, the bushings on the unit should be grounded so that the unit can be replaced. 3-5. When a voltage regulator's control mechanism is tested during a changeout, the unit's bypass switch remains _______________. (open, closed)

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Pole Top Equipment - Voltage Regulators T&D PowerSkills Lineman Training – Edition II Page 48 Appendix A: Glossary This glossary contains terms pertinent to the study of pole top equipment and maintenance. The meanings of the terms are given in that context. Bandwidth - The range of voltages that a voltage regulator control circuit is set to tolerate before causing the regulator to change the load side voltage. Bleeder resistor - A resistor that is designed to drain any charge remaining on a capacitor unit to 50 volts or less in five minutes. Bridging reactor - A device used to connect the taps to the series winding of a step voltage regulator to the line side of a feeder circuit; designed to prevent the circuit from breaking between taps by maintaining contact with at least one tap at all times. Drag hands - Pointers on a step voltage regulator's position indicator that identify the highest and lowest tap positions to which the regulator moved since the hands were reset. Induction regulator - A voltage regulator that adjusts voltage in a continuous fashion within a given range. Position indicator - A dial mounted on the tank of a step voltage regulator that indicates the regulator's tap position. Power factor - The ratio of working power to the total power supplied to a circuit. Reversing switch - A switch used to change the direction of tap movement in a step voltage regulator. Step regulator - A voltage regulator designed to respond to a voltage change by moving from one tap to another in specific steps, or stages. Voltage regulator - A type of variable ratio voltage transformer designed to respond automatically to a voltage that is above or below a predetermined setting.

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