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METER
INSTALLATION
There
are three basic ways to measure electricity consumption:
▪ Small and medium services are metered directly using
direct-connect meters
▪ Large services are
metered using current transformers (CTs) and instrument-rated
meters
▪ Very large services are metered at
switchboards housing CTs and instrument-rated meters
The customer
provides and installs all equipment beyond the point of delivery: meter
sockets, cabinets and enclosures, connection lugs, conduit, grounding,
protection devices, and wiring from the socket to the load.
The
power company provides and installs the meter, current transformers, and
local wiring associated with the meters and CTs.
LOCATING THE
METER
It
is in the mutual interest of the customer and the power company to install
the meter in a location suitable for meter reading, testing, repair, and
removal. Meter locations are subject to approval by the power
company.
Locating
the Meter for a Single-Family Residence
The meter for single-family
residences must be located:
▪
Outside
▪ On the first
floor
▪ On the
front of the house, or on a side wall within 10 feet of the street side of
the house
If the meter is not located on the building, it must be
on a meter pedestal, or on an overhead pole accessible by a power company
bucket truck.
Do not locate meters here:
▪ Behind a fence or enclosure
▪ In areas subject to being fenced or enclosed such as patios, pool
areas, decks, porches, and
backyards
▪ Where shrubs or landscaping
could obstruct access to the meter
▪ In an
unsafe or inconvenient location, such as above a stairway or window
well
▪ On a mobile structure such as a
houseboat or mobile home
▪ Outside bedrooms
or bathrooms, and near doors and windows, to respect customer
privacy.
The requirements listed above for residences also apply to
meters for outbuildings such as detached garages, barns, shops, storage
buildings, pump houses, and other structures that do not provide living
spaces.
Locating
the Meter for a Business
The location of a meter for a business
must be:
▪ Convenient to the power company's
distribution system
▪ On the first floor, or
the first basement
▪ On the front one-third
of the structure closest to normal public access, if the meter is
outside
▪ If the meter is inside, it must be
in an electrical equipment room
▪
Readily accessible by power company personnel
Meters must not
be located:
▪ Behind a fence or
enclosure
▪ In a place where safety could be
compromised
▪ In a location with
abnormal temperature, vibration, or corrosive air
▪ On a pole owned by the power company or another
utility
▪ On a mobile structure such as a
trailer
Avoid locating meters here:
▪
Areas subject to being fenced or enclosed
▪ Areas where shrubs or landscaping could obstruct access to the
meter
▪ Outside bathrooms, and within three
feet of doors and windows, to respect the customer's privacy.
Electrical Equipment Rooms
Meters for business services may
be located in an electrical room. Electrical equipment rooms must:
▪ Contain only power and communication
equipment
▪ Not be used for
storage
▪ Be accessible during normal
business hours
▪ Be well
lit
▪ Be accessible through a door that
opens directly to the outside, or with prior approval by the power company, opens directly to the
lobby of the building's main entrance. If the facility could be locked
during normal business hours (such as a school, church, or meeting
hall), the
electrical equipment room door must open directly to the outside. The
door must be at least 2 feet 8 inches wide and 6 feet 8 inches high,
and open outward. The exterior of the door must have a sign saying "Electrical Room." The customer must
supply a key to the door, and a key box approved by the power company near the door.
METER
INSTALLATION TIPS
Cable runs
▪ Metered circuits and
un-metered circuits must not be intermixed in raceways or enclosures,
except in special
situations approved by the power company.
▪
Customer equipment is not allowed inside a meter enclosure or CT cabinet.
▪ Customer load monitoring
equipment, if installed, must be on the load side of the
meter.
▪ Line-side conductors are connected
to the top terminals of the meter socket, load-side conductors are
connected to the bottom terminals of the meter socket.
▪ After the installation is complete, make
these mechanical checks: Conductors are not under undue strain on their terminals,
connections are tight, terminals are rated for the size of conductor used,
strands have not been removed to make conductors fit under-sized terminals.
Labeling
▪ For multi-meter installations, each meter must
have a permanently engraved metal or hard plastic label which identifies the billing
address.
▪ For four-wire delta
services, identify the high-leg conductor with orange marking and locate
this conductor at the
upper-right jaw of the meter socket, and on the right end of the test
block
Protection
▪ Meter sockets must be equipped with a test
bypass capability. A manual link bypass is required for all
120/240 volt, single-phase services. A safety socket is required for all
480-volt services.
▪
The ampacity rating of the main circuit breaker, or safety switch,
must not exceed the maximum rating of the meter socket. For three-phase
services, if the marked continuous ampacity exceeds 200 amperes,
the customer must install CT metering.
▪
All service equipment must be metered ahead of the disconnect switch,
except in special situations approved by the power company.
▪ Current limiting fuses, which protect the
customer's electrical system from excessive current,
must be located in the customer's service panel or in a separate enclosure
between the socket and the panel.
▪ Ground and bond all meter sockets, enclosures, and
conduit in accordance with Articles 230 and 250 of the NEC. Connect the neutral conductor to the
neutral terminal in the socket.
▪
When metering equipment is installed in a location where it might be
struck by a vehicle, the customer must install and maintain a guard
post
For
more information:
Clearances Around
the Meter
Installation for an
Apartment Building
Installation
for an Office Building
Meter
Sockets
Direct-Connect
Meters
Current
Transformer Metering
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