PUBLIC UTILITY DISTRICT NO. 1 OF LEWIS COUNTY METERING SPECIFICATIONS

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Anne Porter
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1 PUBLIC UTILITY DISTRICT NO. 1 OF LEWIS COUNTY METERING SPECIFICATIONS 1. General Metering Requirements a. Interpretation The District s metering requirements shall not be interpreted to conflict with the regulations of the State of Washington or other regulatory bodies having jurisdiction. The District s metering requirements may be more stringent. b. Meter Location and Accessibility The customer shall provide a location to connect metering equipment. The meter shall be free from obstruction, corrosive atmosphere, abnormal temperature, and convenient to the District s distribution system. All meters, metering equipment, and enclosures shall be readily accessible by District personnel at all times for meter reading, maintenance, testing, installation or removal. All meter locations shall be subject to approval by the District. For overhead service installations, the meter and point of service attachment shall be located so as to provide proper safety clearance for the District s service conductor and to allow for an unobstructed path from the District s distribution transformer to the meter. For underground service installations the meter shall be located so as to minimize the overall length of the service from the District s transformer to the meter. In the case where the service is installed in conduit, the service conduit run shall not contain any condulets or junction boxes ahead of the meter point, and the service conduit run shall not exceed a total of 180 degrees in bends. All conduit runs shall be subject to approval the District. c. Meter Sockets Meter sockets may be ring-type or ring-less and the District will supply the ring. The meter ring shall have a screw type locking mechanism. Snap rings are not acceptable. Meter socket height shall be a maximum of 7 ft. (6 ft. preferred), and a minimum of 5 ft. above finished grade or floor. The center of the meter socket is always the point of reference. 1

2 When a meter socket enclosure is recessed in the building wall, a flushtype socket is required. Building siding shall not cover or overlap the meter base and sufficient space shall be maintained between the socket and siding to permit meter installation and removal, and opening of the socket. Working space in front of metering equipment shall be at least 36 in. wide and 36 in. deep measured from the front of the equipment. Plants, shrubs or trees shall not be planted in this space. Gas meters shall be at lease 3 ft. horizontally from the center of the meter socket enclosure. The center of the meter socket enclosure shall be a minimum of 10 in. from adjacent walls, ceilings, or other similar obstructions. Self contained 200 amp mobile home meter pedestals shall not be allowed. d. Multiple Meter Installations Multiple meter installations may include a main disconnect on the source side of the meters. The multiple meter assembly shall be installed with all meters located a minimum of 3 ft. or a maximum of 7 ft. above floor or finished grade. Each individual meter shall be clearly labeled with the corresponding unit number or the portion of the premises it serves. The labeling shall be of a type that is permanent. Buildings with multiple meter locations, such as businesses in a strip mall where each unit has a separate meter base, shall have each individual meter base clearly labeled with the corresponding unit number or the portion of the premises it serves. The labeling shall be of a type that is permanent. Permanent labeling shall be engraved phenolic nameplates or adhesive die cut labels at least 1-inch high. Hand written labeling such as in pen or pencil, or label maker tape, is not considered permanent. e. Customer Load Monitoring Customer load monitoring equipment shall be installed only on the load side of the District s metering. No customer load monitoring equipment shall be allowed inside a meter or current transformer enclosure. f. Current-Limiting Fuses Current-limiting fuses to protect the customer s electrical system from high fault current shall not be installed in meter sockets, instrument transformer enclosures or District distribution transformers. Currentlimiting fuses may be installed in the customer s service panel, or in a separate enclosure between the meter socket and the service panel. 2

3 g. Residential Meters for single-family structures shall be located on the exterior front wall, or the front one-third of the exterior side of the structure. The front of the structure is the portion facing normal public access. Meter locations will not be approved where access is restricted (i.e., carports, stairways, breezeways, or fenced yards). Metering equipment for mobile or modular homes on private property shall be located at the front one-third of the structure closest to normal public access. Exception of this front onethird requirement for meters may be considered by the District s engineer for special situations; however, any exception must comply with accessibility, minimization of service length and maximum conduit bend requirements of Section 1.b. above. All services (overhead or underground), self-contained or current transformer metered, shall have disconnects on all service feeders. Disconnects shall be located with 15 feet of the meter or current transformer enclosure. The disconnect does not require over-current protection and is necessary in order to have a disconnecting point accessible to the customer and District personnel in the vicinity of the meter. h. Nonresidential Meter sockets and CT enclosures for nonresidential structures shall be installed at a point readily accessible by District personnel. CT enclosures may be located inside an electrical equipment room. The electrical room shall be used solely for power and communication equipment, and must have a door directly to the outside. The electrical room shall be well lit, accessible at all times and shall not be used for storage. The size of the door shall be a minimum of 2 ft. 8 in. by 6 ft. 8 in. The customer shall provide a key for District use and shall install a sign on the exterior door saying, The Electrical Room. Meters shall be located on the exterior of the structure; however, the District may make exceptions and permit the meters in the Electrical Room in multiple meter applications and in hazardous locations. Meters shall not be installed on poles owned by the District or on structures located above the first story level. All services (overhead and underground), self-contained or current transformer metered up to 800 amps, shall have disconnects on all service feeders. Disconnects shall be located within 15 feet of the meter or current transformer enclosure. All self-contained meter sockets shall have a meter bypass provision. 3

4 Services (overhead and underground), 801 amps and above shall be permitted to have service feeders extending in excess of 15 feet beyond the point of metering without disconnects provided that all feeders extend to one central disconnecting point. 2. Self-Contained Metering The line-side (source) conductors shall always be connected to the top terminals of the meter socket. Service conductors shall be arranged in the socket to avoid interfering with the meter installation. a. Single Phase Services: 200 Amps, 240 Volts or less A self-contained meter socket shall be installed on all new and remodeled single-phase services where the current carrying capacity of the service entrance conductors does not exceed 200 amp, as defined by the NEC. 200 amp underground services shall use a self-contained meter socket enclosure with minimum dimensions of 4 ¼ in. deep, 11 in. wide, and 14 in. high and shall have a 2 ½ in. minimum size riser conduit for the source service conductor. b. Single Phase Services: 320 Amp, 240 Volts or less A 320-amp meter socket is permitted on services where the current carrying capacity of the service entrance conductors does not exceed 400 amp, as defined by the NEC. The 320-amp meter socket shall include a bypass arrangement. The 320-amp meter socket shall have a 3-inch minimum size riser conduit for the source service conductor. c. Three Phase Service: 200 Amps or less, 240 Volts or less A 200-amp meter socket is permitted on services where the current carrying capacity of the service entrance conductors does not exceed 200 amp, as defined by the NEC. A manual bypass provision shall be provided. The wild or higher voltage leg shall be landed on the right most terminals in the meter socket to ensure proper metering. d. Self contained services single and three phase greater than 240 volts shall require a test block bypass safety socket in addition to the requirements listed above in sections 2.a.,b., and c. e. Sequence of Equipment With the exception of multiple meter installations, all services, single or three phase with self-contained meter sockets, shall have the sequence of service equipment, meter socket ahead of the disconnect switch. 4

5 3. Current Transformer Metering Current transformer metering is required for services greater than 320 amps single-phase or 200 amps three-phase as defined by the NEC. a. General Requirements The customer is to provide and install a current transformer enclosure ahead of the main disconnect on the outside of the structure or in an approved electrical room. All CT enclosures require a minimum front clearance of 36 inches. Hinged CT enclosures shall not block a safe exit while open. The customer is to provide a CT bracket in all CT enclosures on all services up to 800 amps. The top of the CT enclosure shall be a maximum of 8 ft. and the bottom shall be a minimum of 6 in. above the floor or finished grade. Enclosures shall not be mounted in crawl spaces, attics, any confined areas or mounted on ceilings. The CT enclosure shall have a 3-inch minimum size riser conduit when the source service conductor is District provided. b. CT Enclosure Dimensions Single and three phase CT enclosure sizes and types are listed below. Service Entrance No. of Minimum Type Phase Size (Amps) Transformers Size CT Can Cover to x36 x11 Screw to x36 x11 Hinged to x48 x11 Hinged All current transformer cans 30 x 36 x 11 and larger shall have hinged door(s). c. CT Metering above 801 Amps Current transformer metering for services 801 amps and above shall be completed in the customer s switchboard panel which will be constructed to Electric Utility Service Equipment Requirements Committee (EUSERC) specifications. The EUSERC Specification is No. 322, Instrument Transformer Compartment for Switchboards, and is available upon request at the District. In certain applications and with pre-approval by the District s engineer, the current transformer metering may be installed in the District s distribution transformer. 5

6 d. CT Meter Sockets and Current Transformers Meter sockets and current transformers for all CT metering installations will be supplied by the District but shall be installed by the customer or its contractor. The customer or its contractor shall install the CT enclosure and rigid plastic (Schedules 40 or 80), or EMT conduit between the test switch portion of the meter socket and the CT enclosure. When plastic conduit is used, the customer shall install a green insulated bonding conductor in the conduit. When metallic conduit is used grounding bushings shall be used at both ends. The conduit shall be as short as possible, and shall not exceed 50 ft. in length, and not over 360 degrees in bends. A pull string is required in any meter conduit over 25 ft. Flex conduit shall not be used in meter circuits, except in situations approved by the District s Engineer. Meter circuits shall not contain condulets or junction boxes. The conduit shall be 1-inch minimum for single phase and 1 ¼ inch minimum for three phase. 6

Metering and Service Installation:

Metering and Service Installation: Table of Contents 1. Metering Installation Requirements, General... 1 2. Type of Service... 2 3. Definitions... 2 4. Who Provides Metering Equipment?... 2 5. Establishment of Service... 2 6. Meter Access...