Generac Power Systems 8 kW LP - Manual (Page 13)

Page 11
GENERAL INFORMATION
sEctioN 1.2
iNstallatioN Basics
introduction
Information in this section is provided so that the
service technician will have a basic knowledge of
installation requirements for home standby systems.
Problems that arise are often related to poor or unau-
thorized installation practices.
A typical home standby electric system is shown in
Figure 1 (next page). Installation of such a system
includes the following:
• Selecting a Location
• Grounding the generator.
• Providing a fuel supply.
• Mounting the load center.
• Connecting power source and load lines.
• Connecting system control wiring.
• Post installation tests and adjustments.
SelectinG a location
Install the generator set as close as possible to the
electrical load distribution panel(s) that will be pow-
ered by the unit, ensuring that there is proper ventila-
tion for cooling air and exhaust gases. This will reduce
wiring and conduit lengths. Wiring and conduit not
only add to the cost of the installation, but excessively
long wiring runs can result in a voltage drop.
Control system interconnections between the transfer
switch and generator consist of N1 and N2, and leads
23, 15B and 0. Control system interconnection leads
must be run in a conduit that is separate from the AC
power leads. Recommended wire gauge size depends
on the length of the wire:
max. cable length recommended Wire size
35 feet (10.67m) No. 16 AWG.
60 feet (I8.29m) No. 14 AWG.
90 feet (27.43m) No. 12 AWG.
GroundinG the Generator
The National Electric Code requires that the frame
and external electrically conductive parts of the gen-
erator be property connected to an approved earth
ground. Local electrical codes may also require prop-
er grounding of the unit. For that purpose, a ground-
ing lug is attached to the unit. Grounding may be
accomplished by attaching a stranded copper wire of
the proper size to the generator grounding lug and to
an earth-driven copper or brass grounding-rod (elec-
trode). Consult with a local electrician for grounding
requirements in your area.
the Fuel Supply
Units with air-cooled engines were operated, tested
and adjusted at the factory using natural gas as a
fuel. These air-cooled engine units can be converted
to use LP (propane) gas by making a few adjustments
for best operation and power.
LP (propane) gas is usually supplied as a liquid in
pressure tanks. Both the air-cooled and the liquid
cooled units require a “vapor withdrawal” type of fuel
supply system when LP (propane) gas is used. The
vapor withdrawal system utilizes the gaseous fuel
vapors that form at the top of the supply tank.
The pressure at which LP gas is delivered to the
generator fuel solenoid valve may vary considerably,
depending on ambient temperatures. In cold weather,
supply pressures may drop to “zero”. In warm weath-
er, extremely high gas pressures may be encountered.
A primary regulator is required to maintain correct gas
supply pressures.
Current recommended gaseous fuel pressure at the inlet
side of the generator fuel solenoid valve is as follows:
lP NG
Minimum water column 10 inches 5 inches
Maximum water column 12 inches 7 inches
A primary regulator is required to ensure that proper
fuel supply pressures are maintained.
*
DaNGEr: lP aND Natural Gas arE BotH
HiGHlY EXPlosiVE. GasEous fuEl liNEs
must BE ProPErlY PurGED aND tEstED
for lEaKs BEforE tHis EQuiPmENt is
PlacED iNto sErVicE aND PErioDicallY
tHErEaftEr. ProcEDurEs usED iN
GasEous fuEl lEaKaGE tEsts must
comPlY strictlY WitH aPPlicaBlE fuEl
Gas coDEs. Do Not usE flamE or aNY
sourcE of HEat to tEst for Gas lEaKs.
No Gas lEaKaGE is PErmittED. lP Gas is
HEaViEr tHaN air aND tENDs to sEttlE iN
loW arEas. Natural Gas is liGHtEr tHaN
air aND tENDs to sEttlE iN HiGH PlacEs.
EVEN tHE sliGHtEst sParK caN iGNitE
tHEsE fuEls aND causE aN EXPlosioN.
Use of a flexible length of hose between the genera-
tor fuel line connection and rigid fuel lines is required.
This will help prevent line breakage that might be
caused by vibration or if the generator shifts or settles.
The flexible fuel line must be approved for use with
gaseous fuels.
Flexible fuel line should be kept as straight as possi-
ble between connections. The bend radius for flexible
fuel line is nine (9) inches. Exceeding the bend radius
can cause the fittings to crack.
the tranSFer SWitch / load center
A transfer switch is required by electrical code, to pre-
vent electrical feedback between the utility and stand-
by power sources, and to transfer electrical loads from
one power supply to another safely.
TRANSFER SWITCHES:
Instructions and information on transfer switches may
be found in Part 3 of this manual.
Part 1