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Section 2 Installation
• Service entrance panel with breakers or
fuses and a main disconnecting means
• Grounding system
• Fittings, fasteners, and other hardware
necessary to install the service equipment
underground, from either a pole or trans-
former pad, are called the service lateral. See
Figure 10-2. In either type, these service wires
will be connected to the service entrance
wires at the building.
Most often, the power company will locate
the point of attachment of the service entrance
for the electrician. In many localities this is
required. Check the service specifi cations of
the power supplier to be sure of any addi-
tional requirements before installing the service
entrance. See Figure 10-3.
Where to locate service
When selecting the service entrance loca-
tion, use the following guidelines:
• Underground service entrance conduc-
tors, whether enclosed in cable or conduit,
should be installed in a straight path to
make fi nding the buried conductors easier.
Mast or
riser
Service
drop
To utility
step-down
transformer
Watt-hour
meter
Meter
pan
Service equipment
disconnect and/or
overcurrent
devices
panelboard
Equipment grounding
conductor
(metal equipment
enclosure)
Grounding electrode
conductor
Grounding
electrode
(metal water pipe)
Figure 10-1. This is a typical overhead service drop
and service entrance. (OSHA)
Meter
enclosure
Meter
Service
lateral cable
Transformer
pad
Service
panel
inside house
To utility
power
lines
Figure 10-2. This is a typical underground installation
for a service entrance.
service drop: Overhead wires brought to the building
that are run overhead from the utility pole to the
service point.
service lateral: Underground wires brought to the
building that are routed underground, from either a
pole of transformer pad to the service point.
service point: The point of connection between the
facility of the serving utility and the premises wiring.
Pro Tip
When a piece of equipment is said to be
ahead of the meter, the equipment is on the
transformer side of the meter. Electricians
often use this term when describing where
to locate disconnects, OCPDs, and service
equipment.
Service Location
Conductors brought to the building are
run overhead or underground. Those coming
in overhead from a utility pole are called the
service drop. See Figure 10-1. Those routed