Generac 20kW - Manual (Page 4)

• Before performing any maintenance on the gen-
erator, disconnect its battery cables to prevent
accidental start-up. Disconnect the cable from the
battery post indicated by a NEGATIVE, NEG or (–)
first. Reconnect that cable last.
• Never use the generator or any of its parts as a
step. Stepping on the unit can stress and break
parts, and may result in dangerous operating con-
ditions from leaking exhaust gases, fuel leakage,
oil leakage, etc.

ELECTRICAL HAZARDS 
• All generators covered by this manual produce
dangerous electrical voltages and can cause fatal
electrical shock. Utility power delivers extremely
high and dangerous voltages to the transfer switch
as well as the standby generator. Avoid contact
with bare wires, terminals, connections, etc., on
the generator as well as the transfer switch, if
applicable. Ensure all appropriate covers, guards
and barriers are in place before operating the gen-
erator. If work must be done around an operating
unit, stand on an insulated, dry surface to reduce
shock hazard.
• Do not handle any kind of electrical device while
standing in water, while barefoot, or while hands or
feet are wet. DANGEROUS ELECTRICAL SHOCK
MAY RESULT.
• If personnel must stand on metal or concrete while
installing, operating, servicing, adjusting or repair-
ing this equipment, place insulative mats over a
dry wooden platform. Work on the equipment only
while standing on such insulative mats.
• The National Electrical Code (NEC) requires the
frame and external electrically conductive parts
of the generator to be connected to an approved
earth ground. This grounding will help prevent
dangerous electrical shock that might be caused
by a ground fault condition in the generator set or
by static electricity. Never disconnect the ground
wire.
• Wire gauge sizes of electrical wiring, cables and
cord sets must be adequate to handle the maxi-
mum electrical current (ampacity) to which they
will be subjected.
• Before installing or servicing this (and related)
equipment, make sure that all power voltage
supplies are positively turned off at their source.
Failure to do so will result in hazardous and pos-
sibly fatal electrical shock.
• Connecting this unit to an electrical system nor-
mally supplied by an electric utility shall be by
means of a transfer switch so as to isolate the
generator electric system from the electric utility
distribution system when the generator is operat-
ing. Failure to isolate the two electric system power
sources from each other by such means will result
in damage to the generator and may also result
in injury or death to utility power workers due to
backfeed of electrical energy.
• Generators installed with an automatic transfer
switch will crank and start automatically when
normal (utility) source voltage is removed or is
below an acceptable preset level. To prevent such
automatic start-up and possible injury to person-
nel, disable the generator’s automatic start circuit
(battery cables, etc.) before working on or around
the unit. Then, place a “Do Not Operate” tag on
the generator control panel and on the transfer
switch.
• In case of accident caused by electric shock, imme-
diately shut down the source of electrical power.
If this is not possible, attempt to free the victim
from the live conductor. AVOID DIRECT CONTACT
WITH THE VICTIM. Use a nonconducting imple-
ment, such as a dry rope or board, to free the vic-
tim from the live conductor. If the victim is uncon-
scious, apply first aid and get immediate medical
help.
• Never wear jewelry when working on this equip-
ment. Jewelry can conduct electricity resulting in
electric shock, or may get caught in moving com-
ponents causing injury.

FIRE HAZARDS

• Keep a fire extinguisher near the generator at all
times. Do NOT use any carbon tetra-chloride type
extinguisher. Its fumes are toxic, and the liquid
can deteriorate wiring insulation. Keep the extin-
guisher properly charged and be familiar with its
use. If there are any questions pertaining to fire
extinguishers, consult the local fire department.

EXPLOSION HAZARDS

• Properly ventilate any room or building housing
the generator to prevent build-up of explosive gas.
• Do not smoke around the generator. Wipe up any
fuel or oil spills immediately. Ensure that no com-
bustible materials are left in the generator com-
partment, or on or near the generator, as FIRE or
EXPLOSION may result. Keep the area surround-
ing the generator clean and free from debris.
• These generator sets may operate using one of
several types of fuels. All fuel types are potentially
FLAMMABLE and/or EXPLOSIVE and should be
handled with care. Comply with all laws regulat-
ing the storage and handling of fuels. Inspect the
unit’s fuel system frequently and correct any leaks
immediately. Fuel supply lines must be prop-
erly installed, purged and leak tested according to
applicable fuel-gas codes before placing this equip-
ment into service.
• Diesel fuels are highly FLAMMABLE. Gaseous
fluids such as natural gas and liquid propane
(LP) gas are extremely EXPLOSIVE. Natural gas
is lighter than air, and LP gas is heavier than air;
install leak detectors accordingly.
1-2
Standby Generator Sets
Important Safety Instructions
Safety 001 Re v. 0 08/05