Generac
®
Power Systems, Inc.
9
2.1.1 NFPA STANDARDS
The following published standards booklets pertain-
ing to standby electric systems are available form the
National Fire Protection Association (NFPA),
Batterymarch Park, Quincy, MA 02269:
• NFPA No. 37, STATIONARY COMBUSTION
ENGINES AND GAS TURBINES.
• NFPA No. 76A, ESSENTIAL ELECTRICAL SYS-
TEMS FOR HEALTH CARE FACILITIES.
• NFPA No. 220, STANDARD TYPES OF BUILDING
CONSTRUCTION
• NFPA No. 68, GUIDE FOR EXPLOSION VENTING
• NFPA No. 70, NATIONAL ELECTRICAL CODE.
• NFPA No. 30, FLAMMABLE AND COMBUSTIBLE
LIQUIDS CODE.
• NFPA No. 10, INSTALLATION, MAINTENANCE AND
USE OF PORTABLE FIRE EXTINGUISHERS.
2.1.2 OTHER PUBLISHED STANDARDS
In addition to NFPA standards, the following infor-
mation pertaining to the installation and use of
standby electric systems is available:
• Article X, NATIONAL BUILDING CODE, available
from the American Insurance Association, 85 John
Street, New York, N.Y. 10038.
• AGRICULTURAL WIRING HANDBOOK, obtainable
from the Food and Energy Council, 909 University
Avenue, Columbia, MO, 65201.
• ASAE EP-364.2, INSTALLATION AND MAINTE-
NANCE OF FARM STANDBY ELECTRIC POWER,
available from the American Society of Agricultural
Engineers, 2950 Niles Road, St. Joseph, MI 49085.
• A52.1, AMERICAN NATIONAL STANDARD FOR
CHIMNEYS, FIREPLACES AND VENTING SYS-
TEMS, available from the American National
Standard Institute, 1430 Broadway, New York, N.Y.
10018.
2.2
GENERATOR LOCATION
Install the generator set, in its protective enclosure
outdoors, where adequate cooling and ventilating air
always is available. Consider these factors:
• Install the unit where air inlet and outlet openings
will not become obstructed by leaves, grass, snow,
etc. If prevailing winds will cause blowing or drift-
ing, consider using a windbreak to protect the unit.
• Install the generator on high ground where water
levels will not rise and endanger it.
• This genset must be installed on a level surface.
The base frame must be level within 1/2 inch all
around.
• Allow sufficient room on all sides of the generator
for maintenance and servicing. A good rule is to
allow five feet of space on all sides.
• Where strong prevailing winds blow from one
direction, face the generator air inlet openings into
the prevailing winds.
• Install the generator as close as possible to the
transfer switch. This reduces the length of wiring
and conduit.
• Install the generator as close as possible to the fuel
supply, to reduce the length of piping. HOWEVER,
REMEMBER THAT LAWS OR CODES MAY REG-
ULATE THE DISTANCE.
2.3
GENERATOR MOUNTING AND
SUPPORT
Retain the generator compartment to a concrete slab
with 1/4-inch masonry type anchor bolts. Be sure the
bolts are long enough to retain the compartment. The
slab should be at least six inches thick and should
extend beyond the enclosure to a distance of at least
three inches on all sides. See Section 6 for generator
major dimensions.
2.4
BASIC STANDBY ELECTRIC
SYSTEM
Figure 2.1 shows a schematic diagram of a basic
standby electric system. Both the UTILITY power
supply and the STANDBY (GENERATOR) output are
connected to an approved transfer switch. The trans-
fer switch is required by electrical code and serves
the following functions:
• Allows the LOAD circuits to be connected to only
one power supply at a time.
• Prevents electrical backfeed between the generator
and the UTILITY power circuits.
Notice that both the STANDBY and the UTILITY
power supplies to the transfer switch are protected
against overload by a main line circuit breaker.
Figure 2.1 – Basic Standby Electric System
Section 2 — Installation
Generac Liquid-cooled Generators