INFORMATION & REQUIREMENTS ELECTRIC SERVICE - NStar

ARTICLE 722
722. Pad-Mount Metering
Where a new single customer is supplied from a pad-mounted
transformer, NSTAR Meter Operations Department will
consider locating the instrument transformers on the padmounted
distribution transformer. For location of meter
socket and cabinet/enclosure, see Sketch 24.
The customer will furnish and install:
A. Transformer rated meter socket cabinet, which must have
the NSTAR approved label. See Sketch 24 for location.
NSTAR approved transformer rated meter sockets vendor
part numbers (which are subject to change, refer to
www.nstar.com for most current) are:
• Single Phase Form 4S 6 Terminal Meters
Milbank Cat#UC4964-O-WC-21-NST
Meter Devices Cat#602-U3060A-6-717
• Three Phase, 3 Wire Form 5S 8 Terminal Meters
Milbank Cat#UC4965-0-WC-21-NST
Meter Devices Cat#602-U3060A-8-716
Landis & Gyr Siemens Cat #9837-0905
• Three Phase, 4Wire Form 9S 13Terminal Meters
Milbank Cat#UC4966-0-WC-21-NST
Meter Devices Cat#602-U3060A-13-587
Landis &Gyr Siemens Cat#9837-0906
B. A 1 1/2-inch EMT, rigid metal conduit, schedule 40
conduit, or nipple with pull string shall be provided
between the transformer cabinet and the meter test switch
cabinet/enclosure for the instrument transformer secondaries.
The secondary conductor length between the instrument
transformers and the meter shall be kept to a minimum, and
shall not exceed 75 feet.
ARTICLE 723-730
NSTAR will furnish and install meter and transformer
secondary wiring from the current and potential transformers
to the meter test switch.
723. Primary Metering
Specifications and requirements for the delivery of and
acceptance of service at the available primary voltage,
including provisions for primary metering, will be furnished
upon request. Please contact the NSTAR New Customer
Connect Tech Center.
METAL ENCLOSED BUS DUCT SWITCHGEAR 600
VOLTS OR LESS
730. General
Please contact the NSTAR New Customer Connect Tech
Center for proper dimensions and mounting provisions for
metering current transformers for specific applications.
Approved switchgear and other service equipment must have
the following provisions:
A. A barrier that physically isolates the instrument
transformers from all other equipment. (See Sketches 25
and 26)
B. A separate door for the instrument transformer
compartment with padlocking facilities.
C. Each set of current transformers installed must be cold
sequence and have its own service disconnect.
D. NSTAR will require mounting space for metering and
auxiliary equipment. Refer to section 704 and 720. The
secondary conductor length between the instrument
transformers and the meter shall be kept to a minimum
and not exceed 75 feet. A minimum 30 x 30 x 3/4 inch,
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