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Page 4 of 12
drop in the Upper Chamber of the
Model DV-2 Deluge Valve, and the
force
differential holding the Model
DV-2 Deluge Valve in the set position
is eliminated.
Dry pilot sprinklers are to be minimum
1/2 inch (15 mm) orifice listed or ap-
proved automatic sprinklers, and re-
mote manual pull stations, where re-
quired, are to be Model MC-1 Manual
Control Stations.
Graph B shows the "minimum pilot line
service pressure" as a function of the
water supply pressure. The pressure in
the dry pilot actuation system must be
automatically maintained using one of
the following maintenance devices, as
appropriate.
• Model AMD-1 Air Maintenance De-
vice (pressure reducing type), refer
to Technical Data Sheet TFP1221.
• Model AMD-2 Air Maintenance De-
vice (compressor control type), refer
to Technical Data Sheet TFP1231.
• Model AMD-3 Nitrogen Mainte-
nance Device (high pressure reduc-
ing type), refer to Technical Data
Sheet TFP1241.
NOTES
The dewpoint of the pilot line air pres-
sure must be maintained below the
lowest ambient temperature to which
the dry pilot actuation system will be
exposed. Accumulation of water in the
pilot line connection to the Actuator will
lower the air pressure at which the
Actuator will open and possibly pre-
vent proper operation. Also, introduc-
tion of moisture into the pilot lines ex-
posed to freezing temperatures can
create an ice buildup which could pre-
vent proper operation of the Actuator.
An air dryer must be installed where
the moisture content of the air supply
is not properly controlled at less than
the required value.
It is recommended that an AMD-3 Ni-
trogen Maintenance Device be utilized
in dry pilot actuation system applica-
tions where the dewpoint must be
maintained below -20°F/-29°C. See
Technical Data Sheet TFP1241.
It is recommended that internally gal-
vanized pipe and cast iron fittings be
used for dry pilot lines.
Supervision of the pressure in the dry
pilot actuation system and/or alarm
that separately indicates operation of
the detection system is recommended
and may be required by the authority
having jurisdiction. A dual setting low
pressure alarm switch, such as the
Potter Electric PS40-2A, is suitable for
the service. The recommended pres-
sure settings are as follows:
• Low pressure alarm setting at ap-
proximately 6 psi (0,4 bar) below the
minimum pilot line service pressure
requirement shown in Graph B.
• Fire alarm setting at approximately
15 psi (1,0 bar) below the minimum
pilot line service pressure require-
ment shown in Graph B.
The Pressure Relief Valve (Ref. Item 4
- Fig. 5 ) is factory set to relieve at a
pressure of approximately 45 psi (3,1
bar); however, it may be field adjusted
to a lower pressure if required.
Electric
Actuation
(Basic Trim plus Alarm & Test
Trim plus Electric Actuation Trim)
Electric Actuation is required for elec-
tric operation of the Model DV-2 Del-
uge Valve by a detection system con-
sisting of electrical devices such as
heat sensitive thermostats, smoke de-
tectors, and/or electric manual pull sta-
tions. Information on the various types
of separately ordered Solenoid Valves
that may be used with the Electric Ac-
tuation Trim is given in Technical Data
Sheet TFP2180.
NOTE
Approval by Factory Mutual is contin-
gent on the use of an FM Approved
24VDC Solenoid Valve. FM only ap-
proves solenoid valves for use in non-
hazardous locations.
The Electric Actuation Trim is only to
be used in conjunction with an electric
deluge valve releasing panel (auto-
matic control unit) that is listed or ap-
proved (as appropriate) for fire protec-
tion system releasing service. In
addition, the deluge valve releasing
panel is only to be operated by listed
or approved (as appropriate) fire de-
tectors.
Operation of an electrical device such
as heat sensitive thermostat, smoke
detector, or electric manual pull station
signals the deluge valve releasing
panel to energize the Solenoid Valve.
In turn, the energized Solenoid Valve
opens resulting in a rapid pressure
drop in the Upper Chamber of the
Model DV-2 Deluge Valve, and the
force
differential holding the Model
DV-2 Deluge Valve in the set position
is eliminated.
NOTE
Consult with the Authority Having Ju-
risdiction regarding installation criteria
pertaining to electric actuation cir-
cuitry.
Operating
Principles
The Model DV-2 Deluge Valve is a dif-
ferential valve that depends upon
water pressure in the Upper Chamber
to hold the Center Valve Assembly
closed against the water supply pres-
sure. The nominal trip ratio is 2.5 to 1,
i.e., the Model DV-2 Deluge Valve op-
erates (opens) when the pressure in
the Upper Chamber is reduced to ap-
proximately 40 percent of the water
supply pressure.
When the Model DV-2 Deluge Valve is
set for service, the Upper Chamber is
pressurized through the trim connec-
tions from the inlet side of the system's
main control valve (Fig. 2). Opening of
an actuation device, for example the
solenoid valve in the Electric Actuation
Trim (Fig. 6), releases water from the
Upper Chamber faster than it can be
replenished through the 1/8" (3,2 mm)
Restriction in the Upper Chamber Sup-
ply Connection (Item 8 - Fig. 2). This
results in a rapid pressure drop in the
Upper Chamber and the force differen-
tial holding the Center Valve Assembly
down in the set position is eliminated.
The water supply pressure then forces
the Center Valve Assembly open, per-
mitting water to flow into the system
piping, as well as through the Alarm &
Test Trim (Fig. 4) to actuate system
alarms.
TFP1340
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