Powermate PM400911 User Manual
Page 13
200-2341
13
The engine driving the generator is engineered to
provide reliable power on either Liquefied Propane Vapor
(LPG) or Natural Gas. For proper operation on these
fuels, it is important to deliver gas with adequate energy
content, at sufficient pressure and flow rate. This is
designed to operate on Liquefied Propane Vapor (LPG)
with a minimum energy content of 2500 BTU per cubic
foot or Natural Gas with a minimum energy content of
1000 BTU per cubic foot. This generator is designed to
operate with a fuel pressure at the inlet of the unit
between 7 and 11 inches of water column (4-6
ounces).
Required fuel flow rates for specific models are given
in the table below. To insure correct sizing of the piping
supplying fuel to the generator set, provide the flow and
pressure requirements of this section to a fuel supplier or
licensed plumber during the installation planning stage. If
the fuel supplier cannot guarantee delivery of fuel with
these properties, the generator may not perform as
advertised.
Due to differences in the energy content of fuel used,
it is necessary to derate the output of the generator when
connected to Natural Gas. Additionally, regional and/or
seasonal variations in the makeup of the fuel can further
affect output of the engine/generator system. When
using Natural Gas fuel with minimum properties as
defined, engine output can fall approximately 10% below
that of the same set using Propane Vapor.
F
F
F
F
U
U
U
U
E
E
E
E
L
L
L
L
S
S
S
S
P
P
P
P
E
E
E
E
C
C
C
C
II
II
F
F
F
F
II
II
C
C
C
C
A
A
A
A
T
T
T
T
II
II
O
O
O
O
N
N
N
N
S
S
S
S
A
A
A
A
N
N
N
N
D
D
D
D
C
C
C
C
O
O
O
O
N
N
N
N
S
S
S
S
U
U
U
U
M
M
M
M
P
P
P
P
T
T
T
T
II
II
O
O
O
O
N
N
N
N
R
R
R
R
E
E
E
E
Q
Q
Q
Q
U
U
U
U
II
II
R
R
R
R
E
E
E
E
M
M
M
M
E
E
E
E
N
N
N
N
T
T
T
T
S
S
S
S
W
WA
AR
RN
NIIN
NG
G
•
Natural gas (NG) is highly explosive.
•
Natural gas (NG) is lighter than air and collects
in high places.
•
Liquid propane vapor (LPG) is highly explosive.
•
Liquid propane vapor (LPG) is heavier than air
and collects in lower places.
•
Extreme caution should be taken when working
on a new installation or while performing
general maintenance.
•
Do not smoke when near the unit.
•
Keep flames, sparks, pilot lights, arc-producing
equipment, switches and all other sources of
ignition well away. Keep a type ABC fire
extinguisher handy.
•
Potential for fire or explosion always exist when
using natural gas (NG) or liquid propane vapor
(LPG) as a fuel source. Install this unit in
compliance with all local fuel codes.
•
Do Not operate engine if smell of fuel is present
or other explosive conditions exist.
Per the National Gas Code (NFPA 54 - ANSI
2223.1), a manual shutoff valve in the fuel supply line
to the generator is recommended.
LP Vapor
(ft 3/hr)
LP Vapor
(Gal/hr)
Natural Gas
(ft 3/hr)
PM401211
81
2.2
186
PM409011
79
2.1
176
D
DA
AN
NG
GE
ER
R
•
All fuel system installations MUST BE done by a
licensed plumber or licensed gas technician
and must comply with all applicable codes,
standards and regulations.
FUEL CONSUMPTION TABLE
All values reflect consumption at 100% rated output.