North Star 10500 SBG, Инструкция по установке и эксплуатации

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8
2.6 Fuel System Introduction
The following information is only to assist the
gaseous fuel technician with installation and set-
up. ALWAYS follow LOCAL and FEDERAL gas
codes when installing this product. Consult your
local fuel supplier or Fire Marshall if questions or
installation problems occur.
When installing the fuel system, place a flexible
length of fuel line between the generator fuel
connection point and the rigid piping. The section
of flexible fuel line must be approved for gaseous
fuel use, and meet the requirements as dictated by
LOCAL and FEDERAL gas codes.
It is advised that a manual fuel shutoff valve be
placed in-line with the rigid piping.
This product is designed to operate on either
Natural Gas (NG) or Liquid Petroleum Gas (LPG).
Only use a vapor withdrawal system to deliver fuel
to the engine. A vapor withdrawal system uses
the vapors that are formed on top of the liquid fuel.
Note : This engine only burns vapor fuel.
The fuel system is factory preset for NG. If the fuel
source is LPG, follow the fuel reconfiguration
directions in Section 2.10.
To achieve maximum horsepower from the
engine, the recommended fuels should have a
minimum BTU content of 1,000 BTU per cubic foot
for Natural Gas (NG) and 2516 BTU per cubic foot
for Liquid Petroleum Gas (LPG). See Table 1.5 for
fuel
LPG Conv ersion Factors:
1 lb. = 8.58 cubic feet
1 gallon = 36.39 cubic feet
Table 1.5 - Inlet Fuel Requirements
NG LPG
Pressure
4-6 oz. 7-11” Water Column
Flow
3.25 CFM 9.33 lb/hr, 2.2 gal / hr
BTU/HR
161374 201718
2.7 Fuel System Components
The fuel system is composed of four main
components: fuel lock off, demand regulator, load
block, and carburetor adapter. See Figure 01174.
The fuel lock-off is a safety device that
electrically operates with 12 Vdc. The valve is
open while 12 Vdc is present at its two electrical
terminals. If the engine should fail while
unattended, this device positively shuts off the flow
of fuel. The fuel lock-off has 3/4” NPT inlet pipe
thread, labeled “inlet”. This is the
fuel inlet
connection point.
The demand regulator allows low-pressure fuels
to pass through if 4 ounces of vacuum is applied
to the outlet side of the regulator.
This device is sometimes called a “zero governing”
or “secondary”. The regulator is a vacuum
demand device, which is normally shut when the
engine is not running. Venturi vacuum causes the
secondary regulator to open and allow the flow of
fuel at a zero or negative pressure.
This dev ice is
not to be considered as a satisfactory fuel
lock-off v alve, or a pressure regulator.
The load block is a device that adjusts the fuel
mixture. If this device is set incorrectly, the engine
will experience difficulty in starting, and cause
poor engine performance.
The adapter mounts between the engine
carburetor and the air cleaner. Inside the adapter
is a venturi. The venturi is a symmetrical restriction
that produces a pressure drop (vacuum) and
draws fuel into the air stream. The amount of fuel
drawn in is proportional to the volume and speed
of the air passing through the venturi.
FIG 01174 - Fuel System Components
VENTURI
ADAPTER
FUEL LOCKOFF
(fuel inlet)
DEMAND
REGULATOR
LOAD BLOCK