METERS – METER SOCKETS
The purpose of this policy is to assist electrical contractors and installers with the purchase and installation of metering equipment in DLPUD’s service area. All new and replacement self-contained meter sockets and current transformer cabinets must meet the standards set forth in this directive. Installations made with unapproved metering equipment will not be connected to DLPUD’s service.
1) Inspection – All wiring and other electrical equipment furnished by the Customer will be installed, operated, and maintained by the Customer in conformity with good electrical practice and the requirements of the constituted regulatory authorities. For the customer’s protection, DLPUD must be provided an affidavit or certificate indicating that an inspection has been requested and that the conditions are safe for energization. DLPUD does not assume responsibility for the design, operation or condition of the Customer’s installation.
2) Meter Socket – Inspection of the wiring in the meter socket is the responsibility of DLPUD and no installation shall be energized until connections have been checked and approved by an authorized employee. DLPUD will refuse to install meters or complete the service requirements if violation of electrical codes or hazardous conditions exist.
3) Wild Leg Location – In three-phase, 4-wire Delta services, the phase conductor with the highest voltage-to-ground (wild leg) shall be identified by an orange color tape or by tagging. The “wild leg” service entrance conductor shall be identified at the service head, meter socket, and at any point where connection is made, if the neutral is present.
4) In seven-terminal meter sockets, the wild leg or highest voltage-to-ground service drop conductor shall be connected to the right side terminal of the three-phase meter socket.
602 Single Phase Service
Only Three-Wire Service – Services for single-phase loads shall be three-wire, 240-volt installations. 2-wire, 120 volt service will not be permitted unless 3-wire, 240 volt service is unavailable or the service is for telephone booths, traffic signals or similar loads.
603 Residential Service
1) Residential service entrance sizes up to 400 amp, single-phase will be metered by the use of self-contained meters furnished by DLPUD. See Section 200, 203.2 #2.
2) The meter socket shall be furnished and installed by the customer or electrical contractor. See Exhibit 8.
3) DLPUD requires all residential services to have a by-pass lever mechanism to allow safe installation and removal of self-contained meters for testing purposes. See Exhibit 5.
4) Residential customers requiring uninterruptible service for computers, medical equipment, etc., should also install an approved meter by-pass socket.
5) Residential services, which require in excess of 400 amp, single-phase should contact DLPUD at 847-7609 for more information.
604 Commercial Services
Customer Furnished Socket – Meter sockets for self-contained metering shall be furnished and installed by the customer or electrical contractor. Service entrance sizes up to 400 amp, single-phase, and 200 amp, polyphase will be metered by the use of self-contained meters. See Exhibit 8.
All commercial services using self-contained meters must use an approved lever operated by-pass socket. See Exhibit 5. Such sockets permit uninterruptible service for meter testing or maintenance.
Customer Furnished Cabinet – Cabinets used outside the building wall for current transformers or for a junction point between DLPUD’s service lateral and customer’s service entrance conductor shall be furnished by the customer or electrical contractor.
Metering Transformers – Current Transformers required for metering services in excess of 400 amp single-phase or 200 amp three-phase shall be housed in cabinets placed on outside of building and accessible at all times to DLPUD personnel. All such cabinets shall be furnished and installed by Customer or their contractor as per DLPUD’s specifications.. See Exhibit 9 for preferred examples. Adequate notice must be given (6-8 weeks) to DLPUD on the size and location of the service for timely ordering of CT’s and meters. ** NOTE ** – Metering configurations will not be mounted on DLPUD owned poles.
605 Socket Requirement
Underwriters Lab – All meter sockets must be UL approved or be so marked.
Profile and Rating – Customer must furnish an approved 200 amp or larger meter socket for underground services. This socket must be a minimum of 11 inches wide on single-phase service and 13 inches wide on polyphase service. This width allows for proper bending, crossover clearance, and additional slack in the incoming service wires within the socket. A conduit of adequate size must be installed from the meter socket to 12 inches below grade level.
Round Meter Sockets – Due to limited space for conductors, round meter sockets will not be permitted.
By-Pass Devices – All self-contained meter sockets used for new or rewired commercial installations must be equipped with a lever-operated positive by-pass mechanism. See Exhibit 5.
This requirement includes both single- and three-phase services at all voltages. This will permit the removal of the meter without interruption to customer’s service.
Socket bypasses must be capable of carrying full-load current of the service it is metering on new or rewired commercial sockets. The house meter for apartment buildings and exit light loops require bypasses. Exceptions would be phone booths, and billboards. Any other exceptions must be approved by DLPUD.
Flash Guards – Sockets with manual by-pass devices shall have a flash guard or safety shield. We encourage the use of flash guards on all meter sockets to provide protection from accidental shorts or shocks. This guard will also serve as a guide for easy meter installation.
Automatic Circuit Closing Devices – Sockets with an automatic circuit-closing device that automatically closes the circuit as the meter is withdrawn will not be permitted. The manual by-pass lever shall operate both the by-pass feature and release tension on the meter terminal blades. Moving the lever up bypasses the current around the meter and releases tension on the meter terminal blades. Moving the lever down (operating position) will allow a secure clamping force to terminal jaws, open the by-pass, and return the meter to service.
Ringless Sockets – All meter sockets used on commercial and residential installations, single or multiple positions will be of the ringless type. Ring type will not be permitted.
Socket Location – The general location of the meter socket and service shall be designated by DLPUD. No wiring dependent upon service entrance and socket locations shall be started until these locations have been designated by DLPUD. The meter socket shall be located outside the building adjacent to the service entrance equipment and readily accessible to DLPUD service personnel or meter readers. The customer shall be responsible for providing a location and protection from mechanical damage to the meter and socket. Customer must maintain a clear area of at least four feet in front of the meter and socket. No customer metering or metering equipment shall be allowed on DLPUD owned poles or equipment. Service will not be provided if:
1) Reaching the meter requires company employee to use adjacent property.
2) Gaining access to the meter requires climbing fences or other obstructions or may cause damage to the customer’s walkway.
3) The meter socket protrudes over a walkway or driveway.
4) The meter socket is located so that it may be damaged by moving vehicles.
5) The meter socket is mounted so that ice buildup from roof run-off will cause damage or prevent readings.
Meter sockets shall be installed on the line side of the service disconnect. In multiple occupancy buildings, for residential or commercial use, meter sockets may be installed indoors in one common location if at all times fully accessible to all occupants and to DLPUD personnel. Additional meter rooms may be provided where requirements are in excess of six meters per location. See Exhibit 3.
Socket Height – Outdoor meter sockets should be mounted so that the face of the meter is approximately five feet above the final grade. In no instances will any meter be installed with the top of the meter more than six feet, nor the bottom of the meter less than four feet above final grade. See Exhibit 1.
Socket Mounting – Mounting the meter socket shall be the responsibility of the customer with the following provisions. Meter sockets must be plumb and level and firmly secured to the support with screws of sufficient length and size to hold the socket securely, independent of conduit or cable connections. To prevent condensation, the conduit between a heated area and an outdoor socket or cabinets should be sealed with compound.
607 Current Transformer Cabinet
The customer or electrical contractor will furnish the cabinet to be used as a junction and/or metering point between DLPUD’s service lateral and the customer’s service entrance. This cabinet will be used for current transformers and associated conductor termination and shall be under the exclusive control of DLPUD. The cabinet will be mounted outdoors in a location readily accessible to authorized DLPUD employees. All conduit will be provided by the customer.
The contractor shall refer to DLPUD personnel to discuss details prior to ordering a current transformer cabinet.
Minimum specifications will be:
1) UL approved and meet all applicable codes and be outdoor rated.
2) Complete with landing pads for cable terminations and mounting-bar type current transformers.
3) Hinged door, with provisions for locking and sealing
4) MINIMUM DEPTH OF TEN (10) INCHES.
5) Minimum of 4” raceway between transformer and current transformer cabinet.
The overall dimensions will vary with the required ampacity rating. Ample room should be provided for conductor bending space and ease of termination. See Exhibit 9.
608 Meter Disconnect and Use of Seals
Removing DLPUD Seals and Meters – No one, other than a DLPUD employee or designated representative is allowed to cut and remove or to install a meter seal on any meter, meter socket or other metering device used for metering of DLPUD supplied electricity. The customer, or those found responsible, may be held liable for costs of inspections and re-sealing of any metering where seals are found to be removed or cut by parties other than those designated by DLPUD.
Only in case of an emergency may service be disconnected and seals cut without prior approval of DLPUD. DLPUD must then be notified within 24 hours, excluding weekends and holidays.
During electrical work on a customer’s premises any switchgear, termination cabinets, raceways, etc., connected ahead of and including the meter socket, if left unattended and energized shall be secured with a locking device. After the job is complete, DLPUD must be immediately notified to inspect and approve the installation.
609 Meter Testing
Meters shall be tested for accuracy by DLPUD with the use of standard calibration equipment and generally accepted test procedures, upon request of any customer who believes their meter to be inaccurate. If, upon test, it is found that the meter overran to the extent of an average of 2% or more, DLPUD shall pay the cost of such tests and shall make a refund for overcharges collected since the last known date of accuracy, but for not more than 12 months, on the basis of the extent of the inaccuracy found to exist at the time of testing. If, upon test, it is found that the meter is slow to the extend of 2% or more, the customer shall pay for undercharges since the last known date of accuracy, but not for more than 12 months, on the basis of the extent of the inaccuracy found to exist at the time of testing. If, when the meter is tested upon request of a customer, it is found to be accurate, slow or less than 2% fast, the customer shall be billed the reasonable cost of such testing.