SWITCHING SAFETY & RELIABILITY CONFERENCE

Transcription

1 SWITCHING SAFETY & RELIABILITY CONFERENCE JARGON WORKSHEET Energize (v) Energize is the process of applying rated voltage to circuit or equipment. Modified IEEE or OSHA from Adj. to verb. To make a piece of equipment ALIVE; We use the term energize and would agree with this definition except for the use of the term "rated" a circuit can be energized at voltages other than design levels and be considered energized. IEEE (Modified from Adj.) Electrically connected to a source of potential difference, or electrically charged so as to have a potential different from that of the ground. ( See: alive, IEEE Std [2].) Synonyms: alive; current carrying; hot; live OSHA (modified from adj.): To electrically connect to a source of potential difference, or to electrically charge so as to have a potential significantly different from that of earth in the vicinity. Energized (vt, adj.) Syn. (Alive, Live, Hot) OSHA: Electrically connected to a source of potential difference, or electrically charged so as to have a potential significantly different from that of earth in the vicinity. IEEE or OSHA We use the term Energized and would agree with this definition. Jargon - we use "Hot"; Hot

2 Electrically connected to a source of potential difference, or electrically charged so as to have a potential different from that of the ground. Syn: alive; current carrying; hot; live. OSHA: Electrically connected to a source of potential difference, or electrically charged so as to have a potential significantly different from that of earth in the vicinity. Open (circuit) (n.) Open circuits do not have a complete path for current flow. Open circuits have relatively high resistance. The source potential difference also occurs across the open No Official: An incomplete electrical circuit in which no current flows. The opposite of "closed." In a circuit breaker or other switching device, the state when the switch contacts are apart, the switch is "off," and current cannot flow. Open Operation - The movement of contacts from the closed to open position; Visible open In a circuit breaker or other switching device, the state when the switch contacts are apart, the switch is "off," and current cannot flow. The opposite of closed. In a circuit breaker or other switching device, the state when the switch contacts are apart, the switch is "off," and current cannot flow. The opposite of closed. 2

3 Out Of Service NESC: Lines and equipment are considered out of service when disconnected from the system and when not intended to be capable of delivering energy or communications signals. NESC +: Lines and equipment are considered out of service when disconnected from the system and when not intended to be capable of delivering energy or communications signals. Note: Equipment that is out of service is not necessarily deenergized. Equipment which is unavailable for normal production, service, or use. Equipment which is out of service is not necessarily de-energized. NESC: Lines and equipment are considered out of service when disconnected from the system and when not intended to be capable of delivering energy or communications signals. Qualified Person OSHA: Qualified Employee (qualified person): One knowledgeable in the construction and operation of the electric power generation, transmission, and distribution equipment involved, along with the associated hazards. Note 1: An employee must have the training required by in order to be considered a qualified employee. Note 2: Except as provided in , an employee who is undergoing on-the-job training and who, in the course of such training, has demonstrated an ability to perform duties safely at his or her level of training and who is under the direct supervision of a qualified person is considered to be a qualified person for the performance of those duties. 3

4 IEEE +: Generally, anyone who (1) has met and maintained all current training and qualifications for a specific job, (2) has demonstrated proficiency with rules, procedures, equipment, and hazards associated with the work, and (3) in some organizations is qualified to be issued clearances, request clearances, and/or can perform switching. Qualified Person A person who has received training and has demonstrated proficiency in the work practices involved in their respective job assignments; We use the term Qualified Person and would agree with this definition except for the reference to "Work Protection Code training and qualifications" which we do not reference in our current switching procedures; Personal Qualified to be Issued Clearance: The Construction Operation Team Leaders or Process Owners shall furnish the Dispatching Authority with lists of persons qualified within their departments to be issued Clearances, request clearances and/or can perform switching. The Dispatching Authority shall issue Clearances to listed qualified persons only. This qualified person will be the Person Responsible for Work. Persons qualified to receive a Permission or a Clearance to work on relays, controls, and wiring. A must be on the CONVEX Qualified Person list to be issued a clearance in order to receive a Permission or Clearance t work on relays, controls, and wiring from the CONVEX System Operations Supervisor QUALIFIED PERSONNEL: Personnel who have been trained in correct and safe methods. QUALIFIED: Having been trained in and having demonstrated adequate knowledge of the installation, construction, or operation of lines and equipment and the hazards involved, including identification of, and exposure to, electric supply and communication lines and equipment in, or near, the workplace. An employee, who is undergoing on-the-job training and who, in the course of such training, has demonstrated an ability to perform duties safely at 4

5 his or her level of training, and who is under the direct supervision of a qualified person, is considered to be a qualified person for the performance of those duties. IEEE Std IEEE Guide for Maintenance Methods on Energized Power Lines. OSHA: Qualified Employee (qualified person): One knowledgeable in the construction and operation of the electric power generation, transmission, and distribution equipment involved, along with the associated hazards. Note 1: An employee must have the training required by in order to be considered a qualified employee. Note 2: Except as provided in , an employee who is undergoing on-the-job training and who, in the course of such training, has demonstrated an ability to perform duties safely at his or her level of training and who is under the direct supervision of a qualified person is considered to be a qualified person for the performance of those duties. Induced Voltage Induced voltage is the voltage which is created by relative motion between another conductor and magnetic field. IEEE + Comment Induced voltage is the voltage which is created by relative motion between another conductor and magnetic field. The voltage induced on a network or electric installation by a nearby strike. 5

6 Insulated (adj.) NESC/OSHA: Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current. Note: When any object is said to be insulated, it is understood to be insulated for the conditions to which it is normally subjected. Otherwise, it is, within the purpose of these rules, uninsulated. IEEE or OSHA Separated from other conducting surfaces by a dielectric substance or air space permanently offering a high resistance to the passage of current and to disruptive discharge through the substance or space. Note: When any object is said to be insulated, it is understood to be insulated in a manner suitable for the conditions to which it is subjected. Otherwise, within the purpose of this definition, it is uninsulated. Insulating covering of conductors is one means for making the conductors insulated. NESC/OSHA: Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current. Note: When any object is said to be insulated, it is understood to be insulated for the conditions to which it is normally subjected. Otherwise, it is, within the purpose of these rules, uninsulated. 6

7 Isolate (v) Isolate means to separate equipment from any source of dynamic energy. IEEE Isolate means to separate equipment from any source of dynamic energy. To separate equipment from an source of dynamic energy; Disconnecting from the system by the opening of switches; disconnecting potheads, cutouts, or links; or by cutting or disconnecting conductors (a visual break in the circuit); Separate from electrical source. [To] physically separate, electrically and mechanically, from all sources of electrical energy. Such separation may not eliminate the effects of electrical or magnetic induction. Qualified NESC: Having been trained in and having demonstrated adequate knowledge of the installation, construction, or operation of lines and equipment and the hazards involved, including identification of and exposure to electric supply and communication lines and equipment in or near the workplace. An employee who is undergoing on-thejob training and who, in the course of such training, has demonstrated an ability to perform duties safely at his or her level of training, and who is under the direct supervision of a qualified person, is considered to be a qualified person for the performance of those duties. NESC 7

8 Having been trained in and having demonstrated adequate knowledge of the installation, construction, or operation of lines and equipment and the hazards involved, including identification of, and exposure to, electric supply and communication lines and equipment in, or near, the workplace. An employee, who is undergoing on-the-job training and who, in the course of such training, has demonstrated an ability to perform duties safely at his or her level of training, and who is under the direct supervision of a qualified person, is considered to be a qualified person for the performance of those duties. IEEE Std IEEE Guide for Maintenance Methods on Energized Power Lines See Qualified Person De-Energize De-energize means to disconnect a device or conductor from a power source. Modified IEEE from De-energized? The state of the equipment to check before placing grounds. Adj.: Dead. Refers to current-carrying parts that can be energized but are at present free from any electrical voltage. Said of a transmision line or piece of equipment when disconnecting switches are open and the line or equipment is isolated from the system. To [f]ree from any electric connection to a source of potential difference; not having a potential different from that of the ground. The term is used only with reference to current-carrying parts that are 8

9 sometimes alive (energized). To state that a circuit has been de-energized means that the circuit has been disconnected from all intended electrical sources. However, it could be electrically charged through induction from energized circuits in proximity to it, particularly if the circuits are parallel. Syn: dead. OSHA: De-energized: Free from any electrical connection to a source of potential difference and from electric charge; not having a potential different from that of the earth. Note: The term is used only with reference to current-carrying parts, which are sometimes energized (alive). Clearance Certification issued to a (utility) employee or Qualified Contractor (Distribution only) from Transmission Operations or Distribution Operations that (1) a specific section of the electrical system has been isolated from all known electrical energy source and (2) no switching to energize the deenergized portion of the electrical system covered by the Clearance will be ordered until the Clearance Holder releases the Clearance. Modify IEEE or OSHA: Must combine 4 elements: (1) A Certification/Permission; (2) issued to a qualified person/contractor; (3) for work on an isolated section of the line; (4) on which no switching or any other action until Clearance Holder releases. Also referred to as Work Permit and Permission Work Permit Permission, in written form when required and practicable, granted to a person to perform specified work or test on specified equipment; Certification issued to a (utility) employee or Qualified Contractor from Transmission Operations or Distribution Operations that (1) a specific section of the electrical system has been isolated from all known electrical energy source and (2) no switching OR ANY OTHER ACTION to energize the de-energized portion of the electrical system covered by the Clearance will be ordered until the Clearance Holder releases the Clearance; 9

10 A Clearance is a permission, issued by the Dispatching Authority, to a qualified person to do stated work on equipment after prescribed precautions have been taken and tags have been placed to protect personnel, service and equipment. The clearance will be issued to a qualified person after the necessary switching; blocking, tagging, grounding has been completed, and agreed to by the clearance holder. A formal, scheduled and recorded permission for construction, test, and/or maintenance crews to work on particular transmission lines or components within the BPA system. Issued by a dispatcher at a system control center, coordinated with swtiching schedules to assure equipment is de-energized and safe during maintenance. [A] permission issued by the CONVEX System Operations Supervisor to a qualified person to do stated work on a piece of equipment under the CONVEX System Operations Supervisor's switching and tagging jurisdiction, after prescribed precautions have been taken and tags have been placed for the safety of persons, equipment, and service. A formal, scheduled and recorded permission for construction, tes, and/or maintenance crews to work on particular transmission lines or components within the BPA system. Issued by a dispatcher at a system control center, coordinated with switching schedules to assure equpment is de-energized and safe during maintenance. Clearance: The condition in which a circuit has been de-energized to enable work to be performed more safely. A clearance is normally obtained on a circuit presenting a source of hazard prior to starting work. Syn: outage, permit, restriction. Work permit: The authorization to perform work on a circuit. OSHA: Clearance (for work): Authorization to perform specified work or permission to enter a restricted area. 10

11 Grounded NESC: Connected to or in contact with earth or connected to some extended conductive body that serves instead of the earth. IEEE Connected to earth or to some extended conducting body that serves as earth, whether the connection is intentional or accidental; Lines ore equipment connected to an "approved" ground source on our system. A connection from electrical equipment to ground mat or to the earth, used to insure that the equipment (housing or structure) will be at the same potential (voltage) as the earth. IEEE: Connected to earth or to some extended conducting body that serves instead of the earth, whether the connection is intentional or accidental. Syn: earthed (IEC). OSHA: Grounded, effectively: Intentionally connected to earth through a ground connection or connections of sufficiently low impedance and having sufficient current-carrying capacity to prevent the buildup of voltages that may result in undue hazards to connect equipment or to persons. Lock Out Lock out indicates that an automatic circuit breaker as opened and it will not reclose again without a manual command. No IEEE/NESC/OSHA definitions. Recommend: To physically block or electrically disconnect control a circuit breaker so the device cannot operate, even if called on to do so, without an explicit manual operation or command. Often part of a Lock Out/Tag Out procedure. Lock out indicates that an automatic circuit breaker as opened and it will not reclose again without a 11

12 manual command; We use it as intended by this definition, i.e. a circuit breaker which has been locked out by relay action. We also use the term Lock Out as part of a Lock Out/Tag Out procedure; Physically blocking or electrically disconnecting control so the device cannot operate even if called on to do so. 1) Prevention of a circuit breaker reclosure. 2) A general term that denotes keeping a circuit breaker open following the completion of a predetermined sequence of operations 1) Prevention of a circuit breaker reclosure; 2) A general term that denotes keeping a circuit breaker open following the completion of a predetermined squence of events. Holder The Holder is the person who has accepted the Work Permit or Supporting Guarantee and therefore has attained working and/or testing rights for the work group. The Holder is assigned responsibilities for ensuring that everyone in the work group is protected from the viewpoint of the Code. No IEEE/NESC/OSHA definitions. Recommend: Survey definition with addition of "Clearance Holder" We do not use this term but use the term Clearance Holder for similar purposes. 12

13 Tag (V.) The term used by the dispatcher for the act of placing a danger, attention, hold, or caution tag on a piece of equipment. No Official Definition: The term used by the dispatcher for the act of placing a danger, attention, hold, warning, or caution tag or card on a piece of equipment. We use the term Tag but would define it as "The term used by the dispatcher for the act of placing a Hold Card or Warning Card on a piece of equipment"; Hold card-caution card Ground OSHA: A conducting connection, whether intentional or accidental, between an electric circuit or equipment and the earth, or to some conducting body that serves in place of the earth. Recommend OSHA Grounded Connected to earth or to some extended conducting body that serves as earth, whether the connection is intentional or accidental. A connection from electrical equipment to ground mat or to the earth, used to insure that the equipment (housing or structure) will be at the same potential (voltage) as the earth. A connection from electrical equipment to a ground mat or to the earth, used to insure that the equipment (housing or structure) will be at the same potential (voltage) as the earth. 13

14 A conducting connection, whether intentional or accidental, by which an electric circuit or equipment is connected to the earth, or to some conducting body of relatively large extent that serves in place of the earth. Note: It is used for establishing and maintaining the potential of the earth (or of the conducting body) or approximately that potential, on conductors connected to it, and for conducting body current to and from the earth (or the conducting body). IEEE Std IEEE Guide to the Installation of Overhead Transmission Line Conductors OSHA: Ground: A large conducting body (such as the earth) used as a common return for an electric circuit and as an arbitrary zero of potential. Authorized Employee OSHA: Authorized employee: An employee who locks out or tags out machines or equipment in order to perform servicing or maintenance on that machine or equipment. An affected employee becomes an authorized employee when that employee's duties include performing servicing or maintenance covered under this section. Some confusion/conflict with Qualified Employee/Person. See TF comments. A person qualified by the manager of his/her department as meeting the minimum requirements for a particular category or classification of work and authorized by the department responsible for the facility: a. Operating personnel who are authorized to perform specified operating functions including the issuance of Work Permits, Test Permits, or Operating Orders, or b. Permit holders such as construction, maintenance or test personnel who are authorized to request, receive, and return Work Permits or Test Permits; We use the term Qualified Switchperson in instances where Authorized Employee might be used by other utilities; Qualified switchperson; An individual who has received training in the hazards of our electrical system and basic training in our operations. We do not consider an untrained individual as "authorized." 14

15 We require training to receive a clearance. OSHA: Authorized employee: An employee who locks out or tags out machines or equipment in order to perform servicing or maintenance on that machine or equipment. An affected employee becomes an authorized employee when that employee's duties include performing servicing or maintenance covered under this section. Clearance Boundary The boundary of the Clearance is defined by the tagged switching device(s) which provide Visible Isolation between the area of the system being deenergized and the rest of the electrical system. No Official Definition: Do we need detail from TF comment to the? Must have visible air gap, manually operated switch or jumpers removed. If motor operated or gang operated switch, must be locked or blocked 15

16 De-Energized Free from any electrical connection to a source of potential energy and from electric charge; not having a potential difference from that of the earth. The term is used only with reference to current carrying parts which are sometimes energized. Suggest IEEE. More all-encompassing. A condition in which no potential exists; Free from any electrical connection to a source of potential energy. (Can only say that if the line/equipment is grounded). The term is used only with reference to current carrying parts which are sometimes energized. Dead. Refers to current-carrying parts that can be energized but are at present free from any electrical voltage. Said of a transmission line or piece of equipment when disconnecting switches are open and the line or equipment is isolated from the system. Free from any electric connection to a source of potential difference; not having a potential different from that of the ground. The term is used only with reference to current-carrying parts that are sometimes alive (energized). To state that a circuit has been de-energized means that the circuit has been disconnected from all intended electrical sources. However, it could be electrically charged through induction from energized circuits in proximity to it, particularly if the circuits are parallel. Syn: dead. IEEE Std IEEE Guide to the Installation of Overhead Transmission Line Conductors OSHA: De-energized: Free from any electrical connection to a source of potential difference and from electric charge; not having a potential different from that of the earth. Note: The term is used only with reference to current-carrying parts, which are sometimes energized (alive). 16

17 Emergency NERC: Any abnormal system condition that requires automatic or immediate manual action to prevent or limit the failure of transmission facilities or generation supply that could adversely affect the reliability of the Bulk Electric System. NERC: Any abnormal system condition that requires automatic or immediate manual action to prevent or limit the failure of transmission facilities or generation supply that could adversely affect the reliability of the Bulk Electric System. PLUS TF Comment re saving life and what is NOT an emergency? (1) We use the term Emergency in our switching procedures and employees understand the meaning to be any situation in which lines or equipment must be de-energized at once to save life or property; (2) As it applies to switching: Life or equipment in immediate danger. Note: customers out of power does not constitute an emergency; (3) A condition on the electric system that demands immediate attention; (4) Emergency (unplanned) switching is be defined as the following: Any switching that is required to restore customer load after an outage or to ensure immediate system reliability, safety or integrity as deemed necessary by System Operations. This includes all switching required to issue a clearance after an event. NERC: Any abnormal system condition that requires automatic or immediate manual action to prevent or limit the failure of transmission facilities or generation supply that could adversely affect the reliability of the Bulk Electric System. 17

18 Reclose Modify IEEE to verb form or use with added material from TF comments. We use the term Reclose and employees understand the meaning to be the act of closing an open electrical device to its normally-closed position; An automatic relay action by a circuit breaker, to reenergize a temporarily faulted circuit; Protective relay circuit allows breaker to close after opening for a fault; An automatic attempt to re-energize a tripped circuit. The automatic closing of a power circuit breaker following an opening operation via relay action. The automatic closing of a power circuit breaker following an opening operation via relay action. Automatic Circuit Recloser: A self-controlled device for automatically interrupting and reclosing an alternating-current circuit, with a predetermined sequence of opening and reclosing followed by resetting, hold-closed, or lock-out operation. Grounds Grounds Applied or available IEEE We use the term Grounds and understand the meaning to be "Devices used to create a conducting connection between an electric circuit or equipment and the earth, or to some conducting body that serves in place of the earth"; Mechanical/Electrical equipment used to connect a de-energized circuit or circuit part to ground potential; For clearance purposes: approved conductors to ground out a circuit or equipment. We specify conductor size based on available fault current; Either 30 individual grounds or multiple grounding locations. BPA: A connection from electrical equipment to a ground mat or to the earth, used to insure that the 18

19 equipment (housing or structure) will be at the same potential (voltage) as the earth; [C]onnection from electrical equipment to a ground mat or to the earth, used to insure that the equipment (housing or structure) will be at the same potential (voltage) as the earth. [C]onducting connection[s], whether intentional or accidental, by which an electric circuit or equipment is connected to the earth, or to some conducting body of relatively large extent that serves in place of the earth. Note: It is used for establishing and maintaining the potential of the earth (or of the conducting body) or approximately that potential, on conductors connected to it, and for conducting body current to and from the earth (or the conducting body). IEEE Std IEEE Guide to the Installation of Overhead Transmission Line Conductors: Dead Dead indicates de-energized line or feeder circuit which could or could not be grounded. IEEE adds critical induction warning. Should we add "which may or may not be grounded"? Dead indicates de-energized line or feeder circuit which could or could not be grounded; We use the term Dead and understand the meaning to be "Dead indicates a de-energized line or circuit"; Indicates grounded. A circuit that has been de-energized so that the circuit has been disconnected from all intended electrical sources. However, it could be electrically charged through induction from energized circuits in proximity to it, particularly when the circuits are parallel. See also: de-energized. 19

20 NERC: See De-energized. Isolation Point Isolation Points can be Standard or Non-Standard. A Standard Isolation Point is a device which is capable of being physically positioned or disconnected to control energy sources. A Non- Standard Isolation Point is a device which is not designed to be an isolation point and is prohibited for use as a Guaranteed Device unless it has been documented and approved. No Official Definition: Check conflict with "Clearance Point" Definition No, Clearance Point. Isolating Device: A device in a circuit that prevents malfunction in one section of a circuit from causing acceptable influences in other sections of the circuit or other circuits. Isolated Physically separated, electrically and mechanically, from all sources of electrical energy. Such separation may not eliminate the effects of electrical induction IEEE Disconnected from the system by the opening of switches; disconnecting potheads, cutouts, or links; or by cutting or disconnecting conductors; We use the term Isolated but would define the term as "Equipment separated from any source of dynamic energy ; Separated from electrical source. 20

21 1) Physically separated, electrically and mechanically, from all sources of electrical energy. Such separation may not eliminate the effects of electrical or magnetic induction. 2) Not readily accessible to persons unless special means for access are used. Throwover No Official Definition: Auto/Manual switching action from one circuit to another usually electrical source? Auto/Manual switching action from one circuit to another usually an electrical source; Term used with distribution automated switches of substation services or other 3-position switches used to transfer the load to an alternative source; An automatic switch that transfers load from a deenergized circuit to a live one. Clear OSHA: A utility term meaning to de-energize equipment or circuit normally implying a physical break to prevent re-energization. OSHA + TF comment? A physical break does not necessarily prevent energization; Block and Tag. 21

22 OSHA: A utility term meaning to de-energize equipment or circuit normally implying a physical break to prevent re-energization. Clearance Area A de-energized zone of protection that is bounded by clearance points and is used primarily to protect personnel, but can also be used to protect equipment. No Official Definition:? Some confusion with Working Point, Isolation Point? Isolated area; Protected working point; This would be the Isolated Section ; We call it Work Area; Working Point (a) a specific point in an electric circuit where conductors are to be joined or separated or where contact will or may be made with current carrying parts during the performance of the work, or (b). a specified piece of electrical equipment or apparatus upon which work will be performed Racked Out No Official Definition. Help. Racked out to the Disconnect Position A truck switch with both its main and auxiliary control connections disconnected from all current carrying 22

23 parts of the substation; Racked out to the Test Position A truck switch with its main contacts disconnected from current carrying parts, but with it auxiliary and control contacts still connected; We use the term Racked Out in our switching procedures and employees understand the meaning to be a rack-mounted circuit breaker that is mechanically separated from electrical contact; Used with metal-clad breakers: breaker is physically moved to provide an open air gap; The status of a breaker when blocking and tagging a circuit. Racking: The act of moving a removable element physically between the connected position and the disconnected position in its compartment. IEEE Std C IEEE Standard Requirements for Conversion of Power Switchgear Equipment Clearance Point A point that is locked open (if possible) and tagged with a Danger Tag and is that part of the boundary (open point) between the clearance area and source of hazardous potential. No Official Definition: Check 'Isolation Point' Definition We use the term Clearance Point and understand the meaning to be "A visible isolation point that is locked open (if possible) and tagged with a Hold Card and serves as part of a Clearance Boundary"; A point that is locked open (if possible) and tagged with a HOLD Tag and is that part of the boundary (open point) between the clearance area and source of hazardous potential; Open point 23

24 Operator An operator shall be considered as that individual at a generating or transformer station who exercises Operating Control of specific Bulk Electricity System apparatus. NERC or OSHA System Operator; The System Operator/System Dispatcher is the Dispatching Authority for all substation and distribution equipment, all lines terminating or originating at a substation, and all lines which supply energy to customers. OSHA: System Operator: A qualified person designated to operate the system or its parts. NERC: An individual at a control center (Balancing Authority, Transmission Operator, Generator Operator, Reliability Coordinator) whose responsibility it is to monitor and control that electric system in real time. Hold A status established on a switch or other piece of equipment by the appropriate Jurisdictional Authority declaring that it is not to be operated or its status altered in any way until removed by the same Jurisdictional Authority. + TF comments? Equipment is said to be held off when it is isolated and protected from energy sources and a work 24

25 permit is issued listing the isolation and protection provided. Dead Line A de-energized line or feeder circuit which could or could not be grounded. IEEE definition of "dead" applied to a line? We use the term Dead Line and understand the meaning to be "Dead Line indicates a de-energized line or circuit". Dead: A circuit that has been de-energized so that the circuit has been disconnected from all intended electrical sources. However, it could be electrically charged through induction from energized circuits in proximity to it, particularly when the circuits are parallel. See also: de-energized. Pre-Approved And Pre-Arranged Switching Isn't all switching pre-approved except for emergency situations? Switching sequence for defined procedure written in advance of work, and approved by qualified operators/switchperson; All of our switching is prearranged except for emergency switching and restoration switching, i.e., dispatcher writes 25

26 switching orders and issues start time to switchmen; We also call this a clearance. Working Grounds IEEE? Electrical/Mechanical equipment used to connect electrically isolated circuit parts to ground potential within unobstructed sight of qualified personnel performing work on isolated parts; Personal Grounds Working Ground: See :personal ground. Personal Ground: A portable device designed to connect (bond) a de-energized conductor or piece of equipment, or both, to an electrical ground. It is distinguished from a master ground in that it is utilized at the immediate site when work is to be performed on a conductor or piece of equipment that could accidentally become energized. Syn: ground stick, working ground, red head. IEEE Std IEEE Guide to the Installation of Overhead Transmission Line Conductors 26

27 Zone Of Protection No Official Definition: See TF comments. We do not use this term. We refer to Clearance Area or Clearance Boundaries; Clearance Boundary; Relay schemes. IEEE (for relays) That segment of a power system in which the occurrence of assigned abnormal conditions should cause the protective relay system to operate. IEEE Std C IEEE Standard Definitions for Power Switchgear Approved Practice An approved practice is a trade skill or work procedure used in situations where isolation of energy sources is not used. Skills are developed from a combination of education, training and experience. Approved practices are normally documented in training material, trade handbooks or work methods instructions. Two examples are live line procedures and trouble shooting live equipment. IEEE? An approved practice is a trade skill or work procedure used in situations where isolation of energy sources is not used. Skills are developed from a combination of education, training and experience. Approved practices are normally documented in training material, trade handbooks or work methods instructions. Two examples are live line procedures and trouble shooting live equipment; An approved practice is a trade skill or work procedure. Skills are developed from a 27

28 combination of education, training and experience. Approved practices are normally documented in training material, trade handbooks or work methods instructions. Two examples are live line procedures and trouble shooting live equipment. Approved (NEC): Acceptable to the authority having jurisdiction. Authorization IEEE? We use the term Authorization and understand the meaning to be "the act of conveying authority to a person to perform specific work or actions"; Permission granted by the person responsible for the equipment; The process for reporting a person's qualification to work on various voltage class equipment. The process of verifying that a user or process has permission to use a resource in the manner requested. To assure security, the user or process would also need to be authenticated before granting access. 28

29 Activate Install all sources of power required to open, close or operate a device. No Official Definition: Survey definition? Alive An object is alive when it can deliver energy. It can deliver energy when it is dynamically alive or charged. IEEE? It can deliver energy when it is dynamically alive or charged; We do not use this term. We use the term Live instead; Or live. See Energized. - IEEE Std IEEE Guide to the Installation of Overhead Transmission Line Conductors Alive On Backfeed Alive on back feed indicates that when a circuit disconnect is in the open position, a potential test its load side is still alive. Modify IEEE or use TF comments. 29

30 Alive on back feed indicates that when a circuit disconnect is in the open position, a potential test its load side is still alive; With the local circuit breaker in the open position, an indication via neons, meters, indicating lamps, or high potential test equipment that the feeder is still alive; We do not use this term. We use the term Live instead. IEEE: Backfeed -- To energize a section of a power network that is supplied from a source other than its normal source; The result when power from the secondary system flows back into the primary system because a network protector (switch) remains closed. Isolating Device Isolating device means a device used to separate equipment from any source of dynamic energy. IEEE? Isolating device means a device used to separate equipment from any source of dynamic energy. A device in a circuit that prevents malfunction in one section of a circuit from causing unacceptable influences in other sections of the circuit or in other circuits. IEEE Std IEEE Standard Criteria for Class 1E Power Systems for Nuclear Power Generating Stations 30

31 Equipotential Zones OSHA simple; IEEE more detailed EQUIPOTENTIAL WORK ZONE (area, site) (1) A work zone (area, site) where all equipment is interconnected by jumpers, grounds, ground rods, and/or grids that will provide acceptable potential differences between all parts of the zone under worst-case conditions of energization. IEEE Std IEEE Guide to the Installation of Overhead Transmission Line Conductors. (2) EQUIPOTENTIAL ZONE (Equipotential Grounding) A general term used to describe the application of temporary protective grounds to limit the potential across the worker s body. It is often associated with worksite or single-point grounding, but also includes other applications of temporary grounding. IEEE Std (Revision of IEEE Std ) IEEE Guide for Temporary Protective Grounding Systems Used in Substations OSHA: A zone of equal potential used to protect workers from hazardous step and touch potentials. Adjacent Clearances No Official Definition: Use TF comments? We use the term Adjacent Clearances and would define the term as "Clearances which utilize one or more of the same Clearance Points as an existing Clearance"; Clearances that have a common boundary point. Clearances on parallel lines on 31

32 equipment. Line Status No Official Definition: Use TF comments? We use the term Line Status and would define the term as "Determining whether a line is energized/de-energized or in/out of service"; Condition of lines, including if energized or deenergized. De-Activate Remove source of power used to open, close or operate a device. No Official Definition: Use TF comments? Remove source of power used to open, close or operate a device. Opposite of Activate?? 32

33 Safe Work Area A safe work area is a specifically identified area for work where all known hazards have been eliminated or are controlled. Note: The Work Protection Code is only one component in providing a safe work area. A complete job plan is required for your safety. No Official Definition: Use TF comments? Hot Line Order No Official Definition: Use TF comments? We do not use this term. We use the term Live Line Permit instead; Hot Line Permit: Line is worked energized. Dispatcher tags his controls so he will not manually close the line if it trips until he contacts crew. 33

34 Live IEEE Energized; Energized equipment. See Energized. Electrically connected to a source of potential difference, or electrically charged so as to have a potential different from that of the ground. Syn: alive; current carrying; hot; live. Terminal Clearance?? 34