Tyco AMD-3 Quick Start Manual

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Model AMD-3 Automatic Nitrogen Maintenance Device
High Pressure (Cylinder) Reducing Type with
Field-Adjustable Pressure Regulator
General
Description
The TYCO Model AMD-3 Automat-
ic Nitrogen Maintenance Device is an
automatic, field-adjustable, nitrogen
maintenance device of the high pres-
sure reducing type. The Model AMD-3
Device is utilized in conjunction with a
cylinder of high pressure to control the
pressure in a dry pipe sprinkler system,
preaction system, or dry pilot line sys-
tem of a dry pilot actuated deluge or
preaction valve.
The Model AMD-3 Device features
a two-stage pressure regulator that
maintains a constant outlet pressure,
as the cylinder pressure decreases to
the set point.
Use of the Model AMD-3 Device is
typically specified in applications for
which a dependable plant or local
air supply is not available; the sys-
tem piping requires pneumatic pres-
sure having a maximum dewpoint as
shown in Figure 2; or, the presence of
potentially explosive vapors prohib-
its the installation of an automatic air
compressor.
The Model AMD-3 Device is a re-des-
ignation for the Gem Model F328.
NOTICE
The Model AMD-3 Automatic Nitrogen
Maintenance Devices described here-
in must be installed and maintained in
compliance with this document and
with the applicable standards of the
National Fire Protection Association,
in addition to the standards of any au-
thorities having jurisdiction. Failure to
do so may impair the performance of
these devices.
Owners are responsible for maintaining
their fire protection system and devic-
es in proper operating condition. The
installing contractor or sprinkler manu-
facturer should be contacted with any
questions.
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Technical
Data

Approvals

UL and C-UL Listed
FM Approved
NYC Approved under MEA 206-02-E
Maximum Inlet Nitrogen Supply
Pressure
3000 psi (200 bar)
Field-Adjustable Outlet Pressure
Range
4 to 60 psi (0,4 to 4,1 bar)
Inlet Gauge Range
200 to 4000 psi (1000 to 28000 kPa)
Outlet Gauge Range
4 to 100 psi (30 to 700 kPa)
Cylinder Outlet Connection
C.G.A. No. 580

Assembly

Major components illustrated in Figure
1 are factory-assembled, galva nized
steel nipples and malleable iron pipe
fittings. Connection to the system is via
copper tubing and brass tubing fittings.
Design
Criteria
Unless otherwise specified, nitrogen
cylinders with Outlet Connection No.
580 are supplied with nitrogen having
a dewpoint equal to or less than -60° F
(-51°C) at atmospheric pressure. Figure
2 illustrates the maximum dew-point of
the supply nitrogen as a function of the
system pressure.
The approximate volume "N" of free
nitrogen (that is, at atmospheric pres-
sure) in cubic feet, required to fill a sys-
tem having a capacity of "V" in U.S.
gallons, to a pressure "P" in pounds
per square inch gauge, can be deter-
mined using the formula:
N=0.009VP
JULY 2010
A typical cylinder volume is 242 cubic
feet of free nitrogen, but the actual fig-
ure varies depending on the supplier.
The approximate time "T" in minutes to
fill a system having a capacity of "V"
in U.S. gallons, as a function of system
pressure, can be determined using the
formula:
T=CV
where "C" is a constant determined
from the following table:
System Pressure
PSI
20
30
40
50
60
"C"
0.0400
0.0424
0.0440
0.0451
0.0457
TFP1241